SAFETY-13: the bound came from the wrong half of a two-sided measurement

NOTES.md 5.10 measured the 1.78 kW step BOTH ways - "Up: ~18 s from step to
deadband. Down: ~23 s" (NOTES.md:1550). SAFETY-39 takes 18 correctly: its
bound is a REFUSAL and the looser number refuses less. This branch reused
PLANT_SETTLE_S for the opposite job - how long the plant may still be the
EXPLANATION for a divergence - where the conservative half is the longer one.
ceil(23/2) = 12, not 9, and being short there does not refuse anything, it
accuses.

The false positive is real and is measured here. One inverter, one compute(),
one plant, no second writer anywhere in the harness: the command falls through
zero while the pack is still coasting the old way, unasked_power() calls our
own power "unasked", the counter reaches 9 while it is still coasting, and the
law emits "freeze-released". At the plant's own measured 18 s/23 s shape, over
272 load-step pairs, the 9-cycle bound fires in 62 and the 12-cycle bound in 2.

  PLANT_SETTLE_DOWN_S = 23.0 is added beside PLANT_SETTLE_S = 18.0, because
  the plant's settling time is a PAIR and each bound has to say which half it
  means and why.
  SETTLE_CYCLES = ceil(PLANT_SETTLE_DOWN_S / LOOP_TICK_S) = 12. It is no
  longer the reciprocal of SLEW_RAIL_FRAC; that was a coincidence of both
  reading the same half, and test_control.py now asserts the inequality.
  _SAT_COUNT_CAP moves with it, 10 -> 13. config.yaml accepts
  saturation_cycles as int(1,10), so the whole accepted range is now strictly
  BELOW the bound and the degenerate configuration this branch used to
  document no longer exists - pinned against config.yaml's own schema line.

Three shipped statements were falsified by that measurement and are rewritten,
not renumbered - at 12 the residual is smaller, not zero:

  unasked_power()'s docstring said anything outside the interval "was put
  there by something other than this loop". It was our own power: eight cycles
  after a +1990 W command the command is 0 and the pack still reads +522.3 W.
  control.py said "SO THE BOUND BELONGS TO (b) AND ONLY TO (b)". It fired in
  case (a).
  DOCS.md told an operator "if you see freeze-released, look for the second
  writer" - on a single-inverter install, hunting something that does not
  exist. Replaced by a section that gives the innocent causes first (a large
  load or PV swing; a plant slower than the one measured, 8/320 scenarios at
  23 s rising to 268/320 at 50 s) and the second writer only when the state
  STANDS.

Round 1's own results are kept and re-graded, not weakened. The release/1.0
sweep had to widen to reach the new bound (3780 cases): 3267 bit-identical,
432 releases, 27 command changes - all still charge starts from prev_w == 0 -
and 81 differing in the saturation counter alone, which nothing downstream can
read. The card's case releases on the twelfth saturated cycle instead of the
ninth and settles at the same -1190 W against the same frozen integrator.

Also corrected, because they were claims and did not reproduce: the coverage
table's "output freeze" row was 11, and the mutation form its own note
describes gives 6 on this tree, 6 on the first SAFETY-13 commit and 2 on
release/1.0; the detector row was left at 11 and is 15; the frozen = False
footnote was left at 10 and is 13. And section 6 reported 107 625 as "released
states" when it is the number of states SWEPT - 67 500 of them release, and
both are counted now.

Nothing here reached the inverter. 22/22 test files pass in goodwe-addon-ci,
tree rsynced to a plain path, mounted :ro, python3 -B, __pycache__ purged and
printed first (0 dirs / 0 .pyc; the worktree carries none).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

goodwe_controller/CHANGELOG.md

@@ -1,7 +1,630 @@
 # Changelog
 
+## 0.7.0
+
+⚠️ **SCHEMA CHANGE, AND IT IS WHY THIS IS A MINOR BUMP RATHER THAN A PATCH.**
+[[SAFETY-32]] adds `bms_soc_floor: int(0,50)` as a **required** per-entry key on
+the `inverters` roster - no trailing `?`. A config that declares a roster and
+omits it on any entry is REFUSED at startup. An install running `inverters: []`,
+which is every single-inverter install including the reference one, is
+unaffected: the flat `bms_soc_floor` still describes the one pack.
+
+CFG-04 recorded the rule this follows - the Supervisor keys the built image by
+`version:`, so a schema change without a bump is a schema nobody reads.
+
+Contents, in merge order since 0.6.0 (`2d025ee`):
+
+| | |
+|---|---|
+| `3934ad7` | MAINT-05 - one recalibration per pack, migration graded against the roster |
+| `67e649a` | SPIKE-04a - inverter B and pack B recorded, from datasheet and serial |
+| `3993f9f` | SAFETY-32 - per-pack `bms_soc_floor`, rule 8 per unit, package-wide roster pin |
+| `f72c48d` | UX-01 - add-on configuration in English and Dutch |
+| `86eaef2` | TEL-07 - a second MQTT device for inverter B; A's identity byte-identical |
+| `4482cd8` | SAFETY-41 - the clamp alarm stops narrating normal anti-windup |
+
+⚠️ **0.6.0 WAS NEVER SECTIONED.** Its content sits below this heading rather than
+under one of its own, because the bump shipped without cutting the section. That
+is a defect in this file, not in the release: the deployed 0.6.0 is `2d025ee` and
+the table above is what is new since it. Splitting it retroactively would mean
+guessing a boundary; saying so is more useful than a guess.
+
 ## Unreleased
 
+⚠️ **THE OUTPUT FREEZE NOW HAS AN EXIT, AND ONLY WHERE IT CANNOT END ON ITS OWN
+([[SAFETY-13]]).** While the loop is frozen the command's magnitude may fall but
+never rise; at `prev_w == 0` there is no magnitude left to fall, so a charge
+cannot start. That refusal is deliberate - the inverter reporting power we did
+not command means another writer is on the actuator, the §1.5 non-goal - and it
+is kept. What it did not have was an END: nothing cleared it but the other
+writer leaving.
+
+The exit is now explicit, and *which* freezes get one is the decision rather
+than *how long*:
+
+- A divergence a **limit** could have produced - the inverter doing less than
+  the command, in the command's own direction - **clears itself**, because the
+  command is pinned at something the inverter can reach. It gets no exit, and
+  that is release/1.0's behaviour kept unchanged.
+- A divergence a limit could **not** have produced - the inverter overshooting
+  the command, or producing the opposite sign - may not clear itself at all, so
+  it gets one. It releases once the divergence has outlasted the plant's own
+  measured settling time: `SETTLE_CYCLES` = **12** cycles at the measured tick.
+
+⚠️ **THE BOUND COMES FROM THE SLOWER OF THE TWO DIRECTIONS THE PLANT WAS
+MEASURED IN.** `NOTES.md` §5.10 timed the same 1.78 kW step both ways - ~18 s
+up, ~23 s down - so `PLANT_SETTLE_DOWN_S` (23 s) joins `PLANT_SETTLE_S` (18 s)
+as a named constant. SAFETY-39 uses 18 correctly, because its bound is a
+*refusal* and the looser number refuses less; this bound asks how long the plant
+may still be the *explanation*, and there the longer number is the safe one. A
+bound of 9 derived from 18 fires the exit on a **single inverter with nothing
+else on the bus** - measured in the container, 62 of 272 load-step pairs at the
+plant's own measured shape, against 2 at 12.
+
+⚠️ **`freeze-released` IS A PLACE TO START LOOKING, NOT A FINDING.** It says the
+divergence outlasted the plant's measured settling time. It is **not** proof of
+a second writer: a large load or PV swing can leave our own power coasting
+outside our own command's interval, and a plant slower than the one that was
+measured does the same. DOCS.md now gives the innocent causes first and the
+second writer only when the state *stands*.
+
+⚠️ **RELEASING THE OUTPUT FREEZE DOES NOT UNFREEZE THE LOOP.** The integrator
+freeze is untouched, so the command can only walk, one slew step per cycle,
+toward an accumulator that stopped accumulating when the freeze engaged.
+Measured at the live install's shape (`max_w 5000`, `slew_w 400`,
+`target_grid_w -10`) with another writer holding the pack at +700 W and 2 kW of
+export standing: the command holds at 0 W, starts on the twelfth saturated
+cycle and settles at **-1190 W** against a frozen integrator of -1194 W, not at
+the 5000 W rail. On `release/1.0` @ `c8dcb38` the same run held **0.0 W on every
+cycle**, for as long as the other writer stayed.
+
+⚠️ **THIS IS NOT A REGRESSION FIX AND IT ESCALATES AT TWO INVERTERS.** The
+unbounded block is `release/1.0` behaviour, confirmed cycle for cycle against
+SAFETY-04's branch. At a roster of two, `actual_w` is the SITE SUM, so the
+comparison is a site command against two units' power and one unit still moving
+after the other has stopped can put the site into the block with no external
+actor at all. ⚠️ That escalation is read from the code and from single-unit
+runs; **it is not measured on two inverters.** Inverter B does not physically
+exist yet and `sim/plantsim.py`'s `INVERTER_B` is `INVERTER_A` copied with
+`measured=False`, so any two-inverter figure would be two copies of A.
+
+Graded against `release/1.0` over the 3780-case sweep in `test_control.py`:
+**3267 cases bit-identical, 432 releases, 27 of those change the command** -
+every one a charge from `prev_w == 0` that `release/1.0` refused to start - and
+**81 differ in the saturation counter alone**, because its ceiling moved with
+the bound from 10 to 13. That ceiling change also removes a degenerate setting:
+`config.yaml` accepts `saturation_cycles` up to 10, which is now strictly below
+the release bound, so **no accepted configuration can stop the block engaging**.
+At the old bound of 9 a setting of 9 or 10 deleted it silently.
+
+⚠️ **A PER-INVERTER POWER READING THAT HAS STOPPED FOLLOWING ITS OWN COMMAND IS
+NOW `None`, NOT A HELD NUMBER ([[SAFETY-37]]).** `Inverter.batt` (register
+`0x0518`) goes through a freshness gate: unchanged for >= 35 s *while* the
+standing command is over 250 W *and* has travelled over 250 W since the reading
+last moved. A stale reading is a **missing input**, which §11.1 rule 1 already
+answers with 0 W and keeps commanding.
+
+**This is a behaviour change at the shipped roster of one, and it is deliberate.**
+Before it, a frozen power register read as a healthy measurement for ever - which
+is [[HW-01]], where a value held for 6 h 25 m while the pack drained to its floor
+and every detector read healthy. A healthy install is byte-identical: sixty reads
+of a dithering register under a reversing command all reach the consumers
+unchanged, asserted rather than assumed. A false verdict fails toward 0 W, behind
+the existing `stale_input_s` hold, and clears itself the moment the register
+reports a different value.
+
+At two or more inverters it also removes two false alarms that had no gate at
+all: [[SAFETY-30]]'s per-unit sign check no longer trips on a frozen reading
+(measured: it trips without the gate and NEVER with it - the tick index is
+deliberately not quoted, because it is counted on the wall clock inside
+`cycle()` and is therefore load-dependent; the checkable statement is the
+presence or absence of the trip, which part 3 grades), and
+[[SAFETY-31]]'s circulating-power sensor reports `None` instead of a loop that is
+not happening.
+
+**No new configuration key, and no schema change.** The bound is derived from
+`circulation_hold_s` and `unit_sign_disagree_*`, which the checks read out of
+`config.yaml` at both ends - so moving either default takes the gate red rather
+than leaving it silently too slow. `DECISIONS/SAFETY-37-freshness-policy.md`
+carries the derivation, what [[TEL-06]] and [[TEL-08]] still owe, and three
+named survivors - including the largest: **this detects a value that STOPPED, not
+a value that is WRONG.**
+
+⚠️ **`slew_w` IS A RATIO TO THE RAIL NOW, AND ITS DEFAULT CHANGED FROM 1000 TO 0
+([[SAFETY-39]]).** `0` does not mean "off" and does not mean "unset" - it means
+**follow `max_w`**, exactly as `integrator_max_w: 0` already does, and resolves
+to `max_w / 9`: 222 W at the shipped 2000 W cap, 556 W at the live install's
+5000, 1067 W at a ~9600 W two-inverter site. The 9 is
+`PLANT_SETTLE_S / LOOP_TICK_S` - an 18 s measured step response against a 2 s
+meter tick - so the loop takes the plant's own settling time to cross its whole
+output range at any rail.
+
+**An install that has never set `slew_w` will therefore command smaller steps
+than it did on 0.7.0, and will converge more slowly after a large disturbance.**
+That is the point rather than a side effect: `slew_w: 1000` was derived against
+a **1500 W** clamp in 2026-08 and the live install has run it against 5000 since,
+which crosses the whole range in 10 s against an 18 s plant. Measured on the
+owner's system 2026-09-05: a 3.4 kW export drove the setpoint 380 -> 5000 W in
+five ticks, the battery to -5154 W past a 5000 VA rating, and the grid from
+3.4 kW of **export** to 2.8 kW of **import**.
+
+An explicit `slew_w` is still accepted and is never silently reduced. What is
+new is that a value **faster than the rail allows** is now **REFUSED AT STARTUP**
+(`validate.py` rule 10), graded against the ROSTER SUM - so `slew_w: 1000` with
+`max_w: 5000` will not start. Set it to `0`, or to any value at or below
+`max_w / 9`. Slower is always accepted, including the interim 400 the reference
+install has run since 2026-09-05.
+
+⚠️ **This does NOT fix the over-absorption, and the record says so at length.**
+Re-deriving the slew removes the >= 900 W setpoint step; the loop still absorbs
+~1 kW more than the site needs on a large export step, because that is a `gain`
+term and `gain: 0.6` was measured and deliberately left alone. See
+`DECISIONS/SAFETY-39-slew-against-the-rail.md` §6, and do not read this entry as
+more than it says.
+
+
+**`test_peakguard.py` answered two of its own checks with the wall clock
+(CI-06).** The file sits on the required `checks / unit (pull_request)` context
+and had a measured ~20 % flake rate. It cost a wrong merge diagnosis (parents
+green, merge red — read as a semantic merge conflict, it was the flake), a false
+red on two reviewers' CONTROL runs, and a false "mutation caught" that reached a
+merged card in four places. **A flaky check does not waste a re-run; it
+manufactures evidence for whichever hypothesis the reader already holds.**
+
+Both causes are the control law's own gain `900 / remaining` applied to a
+wall-clock gap the file never intended to have. Neither fix widens anything.
+
+* **The cross-time projection.** The "one cycle of the intent form is exactly
+  the delivered form plus the command standing on the wire" check decided the
+  intent form from a **second** `PeakTracker.project(..., datetime.now())` taken
+  after the real cycle had returned, and compared it against a floor decided
+  from the **first** projection — three lines under a comment saying both run
+  "against the same frozen projection". `excess = 900 × (projected − ceiling) /
+  remaining` moves at `excess / remaining` W/s, so at a 1500 W floor the 1.5 W
+  tolerance bought exactly **`remaining / 1000` seconds**: 333 ms with 880 s
+  left in the quarter, **6 ms with 10 s left**. The gap between the two
+  statements measured **12.7–39.5 ms** over 26 instrumented runs. The check was
+  decided by *where in the quarter it ran*. It now keeps the `Projection`
+  **object** the real cycle graded and decides both forms from it — the clock is
+  out of the comparison and the tolerance is **exact**, not widened. Measured on
+  a real cycle: re-deciding the delivered form from that object reproduces the
+  controller's own floor to **0.000000000000 W**.
+* **The fixture's own room.** `wired_over_limit()` laid telegrams with
+  `range(0, span + 1, 5)`, leaving **0–5 s of the open block uncovered by
+  construction**, and `excess` multiplies an uncovered second back up by
+  `900 / remaining`. Measured on the shipped file: at **12 s of remaining a
+  fixture that asked for a 1500 W floor delivered 613 W (−59 %)**, and at 2 s
+  the guard **did not engage at all** — which fails "the real cycle files the
+  peak claim", "…and the number written to the inverter is the guard's floor"
+  and "the STATUS PAGE row for a floor-limited guard" **together**. The
+  four-attempt retry could not help: four attempts take ~40 ms and all land in
+  the same dying quarter. Fixed with one telegram stamped at `now` (what a real
+  meter does, and what the docstring already claimed) plus `FIXTURE_ROOM_S`,
+  **derived** from the 1 % accuracy the helper promises rather than picked:
+  `net_w × lag / (remaining × want) ≤ 0.01 − lag/900` → **23.6 s → 24 s**, at
+  the measured 0.1 s worst-case lag.
+
+**Nothing was skipped, disabled or marked xfail** — the file still carries all
+of SAFETY-07 and SAFETY-25's forced-discharge SoC floor, and it gains a check:
+the delivered form re-decided from the cycle's own projection must reproduce the
+real controller's number to the bit, which pins the test's `decide()` kwargs as
+main.py's actual call rather than an approximation of it. **One tolerance got
+stricter** (1.5 W → exact), because removing the clock made exactness possible.
+
+**`site_standing` — the one quantity BOTH site guards are asked about — is now
+pinned by a fixture whose per-unit shares cannot answer for it (SAFETY-38).**
+`app/main.py`'s `site_standing = float(sum(standing.values()))` is the first
+argument of [[SAFETY-30]]'s **latching, site-stopping** sign detector *and* the
+`commanded_w` handed to [[SAFETY-18]]'s `looks_frozen()`. It was pinned by
+**nothing**, and three mutations of it disarmed both guards with the whole suite
+green. **This card changes coverage only: not one byte of `app/` moves — the
+shipped `sum` is correct and must not be "fixed".**
+
+* **⭐ THE FIXTURE THE SUITE COULD NOT BUILD: per-unit shares EACH BELOW the
+  site gate whose SUM clears it.** Two simulated units rated 220 W and 280 W,
+  both obeying exactly, inverted gain, house importing 2000 W — the site
+  commands **−500 W against a +2500 W meter** and no single share clears the
+  300 W gate. That is the case the site detector exists for, and it is the only
+  arrangement that can separate `sum` from the mean and from the largest share.
+  `test_watchdog.py` part 9a.
+* **WHY THE EXISTING FIXTURE COULD NOT.** `_sign_site`, the suite's only N≥2
+  site fixture, runs shares of about −2500 W **each** — every one individually
+  over the gate — so sum, mean and largest-share all agree on it. *Its values
+  happen to be equal, and a check comparing two things that happen to be equal
+  cannot see the difference it names.* `MUTATION.md` habit 4, ninth instance,
+  inside the site half of the very card that names it.
+* **FOUR CANDIDATE REDUCTIONS, FOUR DISTINCT ANSWERS, ONE OVER THE GATE** —
+  `sum` −500, mean −250, `max(key=abs)` −280, `[0]` −220 — and that is asserted
+  as a precondition, not described. The asymmetric ratings are load-bearing:
+  equal shares collapse three of the four onto one number, and the **smaller**
+  unit is first so `[0]` stays distinct from `max(key=abs)`. The **gate is the
+  shipped 300 W**; only the hold is shortened, because the hold is a wall clock.
+* **⭐ THE SECOND CONSUMER IS COVERED, NOT SCOPED OUT.** The same value is
+  `looks_frozen()`'s `commanded_w` at `main.py:1926`. At the same roster the
+  site rail is 0.95 × 500 = **475 W**, so `sum` = 500 W rails it while 250, 280
+  and 220 do not. Shipped: the peak guard goes blind on SAFETY-18's conjunction
+  and files `floor_w = 0.0`. Under both surviving mutations it is **not blind at
+  all and files no floor**, so the battery may keep importing through a quarter
+  whose billed average is unobservable. `test_watchdog.py` part 9b. The open
+  quarter is deliberately backfilled with the stuck reading so the mutant cannot
+  reach the same action by the *coverage* route and mask the difference.
+* **AT N=1 NOTHING CHANGES, AND IT IS ASSERTED.** On a real one-inverter
+  controller `standing` has one entry, so `sum`, the mean, `max(key=abs)` and
+  `[0]` are **the same number** — all three mutations are genuinely *equivalent*
+  on a shipped install and no N=1 fixture could ever separate them. Printed and
+  checked, beside the site detector still being absent there. Part 9c.
+* **⚠️ A CORRECTION, AND IT IS THE MOST USEFUL LINE IN THIS CARD.** An earlier
+  revision of this entry said one of the three — `list(standing.values())[0]` —
+  was **already closed** by [[SAFETY-32]]'s package-wide structural pin, and
+  told future authors not to re-cover it. **That was false.** It had been
+  measured **once**, that run hit `test_peakguard.py`'s [[CI-06]] flake (a
+  measured **~20%** false-red rate), and the red was recorded as a mutation
+  **kill**. Re-measured on `release/1.0` @ `86eaef2` carrying only that edit:
+  the **full 21-file suite is green** and `test_peakguard.py` passes **five for
+  five** in isolation — **the mutation survives.** The reason SAFETY-32 cannot
+  see it is not the shape: part 12j taints names *bound* to roster values and
+  lists *accumulated* in a loop, and `standing` is a dict filled by **subscript
+  assignment**, so it never enters the taint set and `sum(standing.values())` is
+  not a roster site at all. 12j's own enumeration on the mutated tree lists
+  `main.py:1553`, `1555`, `1690` — **not `1599`**. **All three mutations needed
+  this card; all three are now covered by it.** *A single red from
+  `test_peakguard.py` proves nothing — re-run it five times in isolation and
+  name the failing check.*
+* **⚠️ AND A ZERO-BYTE SURVIVOR ONE LINE BELOW THE ONE THIS CARD PINNED.**
+  Pinning the *value* `site_standing` said nothing about **where it goes**.
+  Swapping the detector's first two arguments —
+  `evaluate(site_standing, self.grid, …)` → `evaluate(self.grid, site_standing, …)`
+  — is **zero bytes** and left the tree fully green, because the check asserted
+  only that `"-500 W"` appeared **somewhere** in the banner. It still does:
+  **in the meter slot.** The swapped banner reads *"commanded +2500 W against a
+  meter reading −500 W"* — a site charging at −500 W into a +2500 W import, told
+  to the operator **exactly backwards**, on the one line somebody woken by a
+  latching site-stopping alarm reads first. The check now asserts the **ordered
+  pair** rather than a substring, and is red on it. **No `app/` change:** the
+  hole was in the test.
+* **⭐ A SURVIVOR THIS CARD WENT LOOKING FOR AND CLOSED.**
+  `site_standing = float(self.target)` — the arbiter's site *target* instead of
+  the sum of what actually **stands on the wire** — is **−11 bytes** and
+  survived the full suite, because in every fixture that existed the two are the
+  same number. They are not when a device's reported range is narrower than its
+  `max_w`: the `device` claim is filed **per actuator**, so it bounds each
+  unit's share and never the site target. A site asking for −500 W while −250 W
+  stands would then take a **latching site-wide false trip** under its own
+  300 W gate. Closed by part 9a's device-clamped counterfactual.
+* **⚠️ AND THE SAME ZERO-BYTE DEFECT ONE CALL SITE OVER — THE ONE A SHIPPED
+  INSTALL CAN ACTUALLY SEE.** The ordered pair went onto `main.py:1620`, the
+  **site** detector. That detector is armed only at N≥2, and part 9c asserts it
+  is **absent at a roster of one** — so on every install this add-on has, the
+  **per-unit** banner is the only sign-disagreement sentence that can ever be
+  printed, and its call at **`main.py:1560`** was still unpinned. The identical
+  swap there is **0 bytes** and left the tree **21/21 green**, and nothing
+  behavioural could ever have caught it: `disagrees()` is **symmetric** in those
+  two arguments (`commanded_w * against_w < 0`, `abs()` gate on both), so the
+  mutant takes **identical actions on every input**. What moves is the sentence
+  — measured, **9 emitted banner lines invert in 3 distinct sentences**,
+  including the one persisted to `sign_reason` and read back after a restart:
+  *"commanded +1000 W against its own measured power −1000 W"* becomes
+  *"commanded −1000 W against its own measured power +1000 W"*. Closed by the
+  ordered pair on **both** per-unit banners — the N≥2 `its own measured power`
+  one and the **N=1** `a meter reading` one — with both operands read off the
+  **observed cycle** rather than off the arguments the detector was handed, plus
+  a precondition on each that the two operands really are different and opposite
+  in sign. **Red on four named checks, green in the other twenty files. No
+  `app/` change.**
+* **⭐ AND THE FAMILY IS NOW ENUMERATED BY MACHINE, because it had been
+  enumerated by hand twice and was short both times.**
+  `tools/symmetric_message_scan.py` finds every call whose argument order is
+  load-bearing for a **message** rather than for a decision: it renames each
+  parameter pair, erases every formatted string, canonicalises the commutative
+  operators and iterates to a **fixpoint** (the symmetry is usually one call
+  deep — `evaluate()` is symmetric only *through* `disagrees()`), then
+  classifies each sentence by where it goes. A second census covers sentences
+  the **caller** builds. It found **one open survivor this card does not close
+  and now discloses** — `rail_unreachable()`'s `dev_min`/`dev_max` at
+  `main.py:3208`, **0 bytes, 21/21 green**, a status-page row — and **twelve**
+  unpinned caller-built sentences including SAFETY-31's `circ_reason`, which is
+  the same shape and is also persisted. The list, the pinned status of every
+  member and the instrument's own blind spots are in
+  `DECISIONS/SAFETY-38-site-standing-pin.md` §7.
+* **⚠️ AND A LEDGER SENTENCE THIS CARD ITSELF GOT WRONG, CORRECTED WITH THE
+  MEASUREMENT.** An earlier revision said *"before part 9 existed, **three** of
+  these left the whole suite green — M1, M2 and M3 — and the remaining seven
+  were caught by SAFETY-30's own N≥2 checks"*. **Eight** did. Re-run one at a
+  time on clean `release/1.0` @ `bbc903b`, fresh copy each, bytecode purged,
+  byte delta and `main.py` fingerprint printed, **full 21-file suite** every
+  time: M1, M2, M3, M4, M7, M8, M9 and M10 are all **21/21 PASS**; only M5 and
+  M6 go red. It is the same species of error this round exists to fix — **a
+  survivor recorded as a kill** — and the file contradicted itself three times
+  while saying it. **And the two that ARE caught make the card's case:** M5
+  (`sum(abs …)`) and M6 (`-sum`) are the only two that reverse the **sign**.
+  Every other entry changes only the **magnitude**, and the old `_sign_site`
+  fixture's ~−2500 W shares put nine different magnitudes on the **same side of
+  the same 320 W gate**. The pre-existing coverage could see a sign and nothing
+  else.
+* **13 mutations — 11 of that line and its call site, plus 2 zero-byte edits to
+  the arbiter claim wiring — each on a fresh full-repo copy mounted `:ro`,
+  bytecode purged by `tools/mutation_run.sh`, the edit re-read from disk and the
+  byte delta printed. All 13 red.** Every one was **re-run independently** in
+  this round rather than carried forward from the previous round's report. The
+  claim-wiring pair (`sign_site` and `circulation` moved from site scope to unit
+  scope) closes two gaps a reviewer disclosed — though **`circulation`'s kill
+  belongs entirely to pre-existing checks and is not claimed by this card.**
+  ⚠️ One **false red** from `test_peakguard.py` on M10 did not reproduce in four
+  subsequent runs; it is CI-06's known flakiness, no claim here rests on it, and
+  it is recorded rather than quietly dropped — unlike the one that *was*
+  believed, two bullets up. Ledger, and an **enumerated list of what was not
+  mutated**, in `DECISIONS/SAFETY-38-site-standing-pin.md` §4a, §4b and §6a.
+* **⭐ ROUND 4: THE SCANNER COVERED ONE SYNTACTIC SINK AND CALLED IT THE
+  FAMILY, AND TWO LIVE MEMBERS WERE SITTING IN THE HOLE.** Every one of census
+  B's 16 members was a sentence that is **appended, assigned, or logged**. Not
+  one was **RETURNED** — and census A's return bucket only ever held a callee
+  formatting its own *parameters*, so a method formatting its own **attributes**
+  and handing the string back was invisible to both. That is the whole
+  `describe()` / `explain()` family, which is where this codebase keeps its
+  operator sentences. **Worse than the gap: it was in none of the five blind
+  spots the tool printed about itself.** The tool now scans the return sink
+  (census C), resolving it through the returning method's **call sites** so that
+  a returned *key* — `store.unit_key()`, `mqtt.unit_state_key()` — is not
+  mistaken for a returned *sentence*; it also scores a sentence handed to a
+  constructor as `reason=` or placed under a `"text"` dict key, which added
+  **six more caller-built members** it had been stepping past. Re-run, it
+  **rediscovered both of the members this round was sent to fix without being
+  told where to look**.
+* **⭐ `ClampResult.describe()` — the clamp alarm the owner has been complaining
+  about all day — had a SECOND independent way to lie, and no `test_*.py`
+  mentioned `describe()` at all.** Transposing `requested_w` and `applied_w` in
+  `clamp.py:253` is a **zero-byte** edit that leaves the guard reporting a
+  setpoint clamped **UPWARD**, in the measured case to +9999 W by a bound whose
+  rating the same sentence gives as 2000 W. It is the §15 action-log row
+  (`main.py:1366`) **and** the ClampWatchdog notification reason
+  (`main.py:2452`). Measured **21/21 green** before; now **red on 4 checks** in
+  `test_clamp.py` part 6d, pinned on the **ordered pair** on the contiguous
+  literal at **both** consumers, with operands read off `ctl.target` and
+  `hass.writes[-1]` — what the loop asked and what the device was sent — rather
+  than off the `ClampResult` the swap lives in.
+* **⭐ `PeakDecision.explain()` — the status-page banner — the same shape.**
+  `projected_w` ↔ `ceiling_w` at `peakguard.py:493`, **zero bytes**, and the
+  row then reads *"quarter projects 5013 W under a 2300 W ceiling"*: a quarter
+  **2713 W over** its ceiling, on a row whose own words say *idle* and whose own
+  flag says **ok**. `"peak guard idle"` appeared in no `test_*.py`. Measured
+  **21/21 green** before; now **red on 3 checks** in `test_peakguard.py` part 13,
+  pinned on the decision and on the shipped status row at `main.py:3313`.
+  ⚠️ **A correction the ticket is owed:** the idle sentence does not reach
+  `main.py:3299/3302` — those are the *floor-limited* branch, where `explain()`
+  returns `self.reason` before the idle literal is built. It reaches
+  **`main.py:3313`** and, on the release edge, `main.py:1951`.
+* **`test_arbiter.py`'s scope-violation check made a claim WIDER than its
+  assertion** — it said `scope_violations` *"names the source and the actuator
+  it does not belong on"* and asserted `"peak" in scope_errors[0]`, which is
+  still true after the two swap roles. Measured this round: **0 bytes, 21/21
+  green**; now red on 2 checks, pinned on the ordered pair.
+* **14 more zero-byte mutations measured, and 10 SURVIVORS ARE DISCLOSED RATHER
+  THAN CLOSED**, each with its file fingerprint and its 21/21 verdict, in
+  `DECISIONS/SAFETY-38-site-standing-pin.md` §7e–§7g: **two** in
+  `allocator.py`'s `UnitPlan.explain()`, three across `arbiter.py`'s two
+  `explain()`s, two in `tariff.py`, two in `arbitrage.py`'s trade reasons and
+  one in `main.py`'s SoC-floor notification. The other four of the fourteen are
+  kills: `allocator.py:162` was already caught by `test_alloc.py`, and
+  `clamp.py:253`, `peakguard.py:493` and `arbiter.py:264` are closed here. **An enumerated list with honest
+  gaps beats a fifth round finding a fifth instance.**
+  ⚠️ **And the probe that grades those mutations was itself the defect, once.**
+  Its first cut numbered the operands **by order of appearance**, so after a
+  transposition the other leaf took the same number and all thirteen renders came
+  back **byte-identical** — which reads exactly like *the edit is inert*. Keying
+  the value to the **name** fixed it. A measurement comparing the swap against
+  itself, in the instrument this time.
+* **The tool now states what it does NOT scan**, largest hole first:
+  `%s`-style lazy logging (`_LOG.error("… %s … %s", a, b)` puts the operands in
+  *arguments*, so no census here looks at them and the transposition is the same
+  zero-byte edit — **31 such calls across 8 modules, counted and listed by the
+  tool rather than asserted**), `.format()`/`%`/`+`/`.join()` sentences, a sentence that
+  leaves through a dict or dataclass and is rendered elsewhere, `yield`ed
+  sentences, message attributes outside the `reason`-shaped set, and everything
+  outside `app/`. Its five over/under-report gaps stay, and every census row now
+  prints whether the two interpolations **share a format spec** — the difference
+  between a transposition that is silent and one that merely looks broken.
+
+**Inverter B gets its own MQTT device, and inverter A keeps the one it has
+(TEL-07).** MQTT discovery announced **one** device, and every entity hung off
+one `unique_id` prefix, so at two inverters B's per-unit telemetry had nowhere
+to go. It has one now — **without touching a single entity that already
+exists.**
+
+* **⭐ A's discovery payloads are byte-identical to `release/1.0`.** Same topics,
+  same `unique_id`s, same payload bytes, same retain flags, in the same order —
+  verified by **diffing the announced payloads**, not by reading the code:
+  `9 topics, 0 missing, 0 changed, 0 added` at a roster of one, and
+  `0 missing, 0 changed, 8 added` at a roster of two. That is what protects the
+  live install's recorded history and the three watchdog automations that name
+  its entities.
+* **⚠️ THE ASYMMETRY IS DELIBERATE — DO NOT "CLEAN IT UP".** The first roster
+  entry's per-unit rows go on **the device it already has**; every later entry
+  gets its **own** device (`via_device` the controller). "One device per
+  inverter" is tidier and is the change that renames every entity on the live
+  system — and because HA keeps the id it composed at first discovery, a rename
+  produces a **new entity beside a dead one**: the history stays behind and
+  every dashboard, template and automation goes on pointing at a sensor that
+  quietly stopped updating. The composed ids come out symmetric anyway
+  (`sensor.goodwe_inverter_a_battery_power` /
+  `sensor.goodwe_inverter_b_battery_power`).
+* **Four per-unit rows** — setpoint, battery power, SoC and the SAFETY-02 sign
+  latch — announced **only from a roster of two**. At N=1 nothing is announced
+  and nothing is published: no second device, no renamed entity, no added topic,
+  asserted rather than assumed.
+* **Site-scoped sensors stay site-scoped.** `grid` and `p1_sample_age_s` are
+  announced **once**, on A's device, at every roster length 1–6. There is one P1
+  and one grid connection, and `p1_sample_age_s` is a **watchdog input** — a
+  second copy is a second answer to "is the meter fresh?", one of which is
+  always the one nobody is looking at. Circulating power, controller status,
+  maintenance phase and the capacity-tariff peak are site for the same reason.
+* **`inverter.roster_names()`** is now the one answer to "what are the units
+  called", read by `build_roster()` **and** by the publisher — which has to know
+  the roster **before** a `Controller` exists, because announcing happens on the
+  broker's CONNACK.
+* **`test_mqtt.py`**, a new suite: the recorded `release/1.0` baseline
+  (generated by running that commit's module, not transcribed), the payload
+  diffs, the composed entity ids modelled **independently** of `app/mqtt.py` and
+  anchored on the one id verified against the live system
+  (`sensor.goodwe_p1_sample_age`), the announcement-vs-publication agreement on
+  a real `Controller` with **different** SoC, battery sign and latch state on
+  the two units, and **twelve mutations of the shipped module, all red, each on
+  a named property**.
+* **MEASURED, NOT ASSERTED.** Three of those properties exist because the
+  mutation table found their absence: dropping the unit from the *state topic*,
+  moving `grid` into the per-unit set, and `units=()` in main()'s publisher call
+  were all **green** on the first run. So was a roster fallback that named two
+  nameless entries `inverter-a`. Sixteen mutations were run through
+  `tools/mutation_run.sh`; the survivors are enumerated **with their size** in
+  `test_mqtt.py` part 9.
+* ⚠️ **Inverter B does not physically exist** (~2026-09-12). Every fixture here
+  is **simulated**, from the datasheet and serial in `NOTES.md` §1.1b. Nothing
+  in this card was measured on a second inverter.
+
+**The add-on configuration screen now speaks English and Dutch instead of raw
+option keys (UX-01).** There was no `translations/` directory at all, so Home
+Assistant fell back to rendering the option KEYS — an operator opening
+*Configuration* read `unit_sign_disagree_w`, `saturation_cycles`,
+`integrator_max_w`, seventy of them, in file order, with no description and no
+way to tell a constant derived from 1890 closed-loop test runs from their own
+inverter's rating. **This card changes presentation only: not one default, not
+one range and not one line of behaviour moved.**
+
+* **`translations/en.yaml` and `translations/nl.yaml`**, with a `name` and a
+  `description` for **all 70 options** and for **all 7 per-entry keys** of the
+  `inverters:` repeatable section. The Dutch is written for a Flemish
+  homeowner rather than transliterated: *afname* and *injectie*, *kwartierpiek*
+  and *capaciteitstarief*, *laadniveau*, *uitschakelgrens* — the words that are
+  on the bill and on the meter.
+* **⭐ EVERY DERIVED CONSTANT SAYS WHERE IT CAME FROM AND WHETHER TO TOUCH IT.**
+  `unit_sign_disagree_s` now reads *"derived from 1890 closed-loop test runs
+  (SAFETY-30): 85 s is 8.5 times the worst legitimate opposition those runs
+  produce… do not change it without re-deriving"*; `circulation_w` cites its 924
+  runs and the measured 400 W knee; `meter_freeze_s` cites the 2399 s capture;
+  `bms_soc_floor` says it is register `0x0560` read off the pack. The two
+  numbers that are genuinely the operator's — `max_w` and `peak_cap_w` — say
+  **"THIS IS YOUR NUMBER"** instead, and `cycle_cost_threshold_eur`, which is
+  neither measured nor the operator's, admits it is an open product question
+  (OPT-08) rather than borrowing the others' authority.
+* **`config.yaml` reordered into task order** — hardware/entities → meter →
+  ratings and limits → tariff → maintenance → safety → advanced — in **both**
+  halves, with every comment carried with its key. ⚠️ The rendered order is the
+  **`schema:`** half's (`App.schema_ui` is `UiOptions(...)(data["schema"])`);
+  the `options:` half is reordered to match so the file reads the way the tab
+  renders. ⚠️ **`test_inverter.py` part 12's first-match trap is preserved**:
+  the nested per-entry `max_w:` still appears BEFORE the flat one under
+  `schema:`, and `inverters: []` still ships in the `options:` half. Moving the
+  nested block below the flat one is a **1-byte** edit and it was run: red in
+  `test_inverter.py` and in `test_translations.py`.
+* **MEASURED, NOT ASSERTED.** `tools/supervisor_shape_probe.py` gains a section
+  F that loads both files with Supervisor 2026.08.0's *own*
+  `_read_app_translations()` out of the release image (a file that fails
+  `SCHEMA_APP_TRANSLATIONS` is **dropped with a log warning and nothing else**),
+  runs its own `UiOptions`, replays the frontend's label resolution transcribed
+  from the shipped bundle, and prints every rendered row in both languages.
+* **⚠️ ONE MEASURED NEGATIVE RESULT, RECORDED RATHER THAN GLOSSED.** The
+  per-entry keys inside the `inverters:` repeatable section still render RAW.
+  `_convertSchemaElement` sends `type: "schema"` **with** `multiple` to
+  `ha-selector-object`, which labels its fields `fields[name].label || name`,
+  and the converter sets neither `label` nor `translation_key`. The `fields:`
+  translations are shipped and validated because that is the shape Supervisor's
+  own schema defines for exactly this, and a frontend that wires `label` through
+  would consume them — but on 20250925.1 they do not reach the screen, and this
+  card does not claim they do. The `inverters` label and description themselves
+  do.
+* **A new check, `test_translations.py`, so this cannot rot.** A translation key
+  naming an option that does not exist, or an option with no translation, fails
+  CI — in both directions, for both languages, top-level and per-entry. It is
+  **mutation-tested both ways**: eleven mutations applied in-process, each
+  required to NAME the key it broke rather than merely to go red, plus a
+  negative control that the unmutated input is clean. Two of the eleven are the
+  ones that cost the WHOLE FILE rather than one label — an unrecognised
+  top-level block, and a `network:` value that is not a string. Supervisor
+  validates each translation file through `SCHEMA_APP_TRANSLATIONS` and, on
+  refusal, **logs a warning and drops all of it**, so those silently return the
+  entire tab to raw keys; neither is reachable through the `configuration:`
+  coverage, which is why they were hunted for and closed. Six more were run **on disk**, through the
+  purge-and-re-read protocol: deleting a translation (−65 B), renaming an option
+  in `config.yaml` (+4 B), adding an orphan key (+47 B), emptying a Dutch
+  description (−711 B), breaking one label's group prefix (−4 B) and deleting a
+  provenance citation (−19 B) each go red.
+* **The parser has a licence.** There is no PyYAML in the add-on's CI image, so
+  `tools/translations_lint.py` reads these files by hand — and a hand parser
+  that quietly disagrees with the real loader is the defect this repository
+  keeps finding. The probe imports **that same module** and asserts, key by key
+  and string by string, that it returns what `_read_app_translations()` returns.
+  The parser is deliberately strict and **raises** on anything outside the
+  subset; nine malformed shapes are fed to it to prove it does.
+* **⚠️ WHAT THIS CHECK CANNOT SEE, stated with its size.** It grades coverage
+  and provenance *citations*, not truth. Falsifying a figure inside a
+  description that is not one of the cited tokens survives (run: *"8.5 times"* →
+  *"3 times"*, −2 B, green), and swapping two options' descriptions survives
+  (0 B, green). Separately and out of this card's scope: changing a shipped
+  default that no suite pins survives — `step_w: 10` → `20` (0 B) leaves
+  `test_control.py`, `test_clamp.py`, `test_validate.py` and
+  `test_peakguard.py` green. That is the same family as CFG-04's DEFECT 2 and
+  the UX-01 rescope moved it to its own card on purpose.
+
+**Inverter B's rating is 4600 W, FROM ITS DATASHEET, and every documented copy
+of it now says so (SPIKE-04a).** Three places stated B's rating — `config.yaml`'s
+commented roster example, `DOCS.md`'s, and `tools/supervisor_shape_probe.py`'s
+"a blob an operator would POST" — and all three said **3000 W**, a number that
+was never measured, never read off a datasheet, and simply wrong. The owner
+supplied B's model and serial on 2026-09-04: a **GoodWe GW5048D-ES**, serial
+`55048ESU22AW0992`, max charging and discharging power **4600 W**. No control
+behaviour changes here; this is documentation and its pin.
+
+* **Serial characters 6-8 read `ESU`** → platform 105, AA55, the supported set.
+  Not `ESN`/`ESC` (ES G2, platform 745). SPIKE-01 does not gate this site.
+  ⚠️ A passed platform gate is **not** a proven control surface: `specs.md`
+  already calls other platform-105 serials *"same protocol family; untested
+  silicon"*, and this repo's `0x056E`/`0x056F` map was reverse-engineered from a
+  passive tap on **one BPS unit**. That check is the bench half of SPIKE-04.
+* **⚠️ 4600 W IS FROM A DATASHEET AND IS NOT A MEASUREMENT, and one ambiguity is
+  recorded rather than guessed.** The datasheet prints it under *Battery Input
+  Data*, so it is probably **DC**, while `max_w` is graded against `0x0518` —
+  the inverter's own **AC** power. If it is DC the AC ceiling is nearer
+  4600 × 0.94 ≈ **4324 W**, and the charge direction moves the other way
+  (≈ 4894 W drawn AC-side). **Neither reading is written in as fact.**
+  SAFETY-20's `min(max_w, dev_max)` already bounds it correctly under either,
+  once `dev_max` is read off the unit — so `max_w: 4600` is what to configure
+  today. `goodwe/NOTES.md` §1.1b carries the full record, with the date and the
+  method on every figure.
+* **A NEW CHECK, BECAUSE A DOCUMENTATION FIX WITHOUT ONE DRIFTS AGAIN.**
+  `test_validate.py` now pins all three documented rosters: they must be
+  findable, they must agree, and they must say **4600**. It also grades the
+  **provenance beside the number** — the datasheet it came from, the `0x0518`
+  it is graded against, and the 4324 W the DC reading would make it — **within
+  2500 characters of the roster, not file-wide.** The first version searched
+  whole files and was already vacuous on two of them, because `0x0518` appeared
+  in `config.yaml` and `DOCS.md` for unrelated reasons before this card: a
+  check whose data could not reach the failure it named, in the file that
+  exists to complain about those. Four mutations were run against the fixed
+  version — the probe back to 3000 (0-byte delta), the `DOCS.md` caveat
+  deleted, `config.yaml` alone "corrected" to 4324 (0-byte delta), and the
+  probe's entity renamed so the regex finds nothing — and all four are red.
+* **THE TEST FIXTURES KEEP 3000 W ON PURPOSE, AND NOW SAY WHY AT THE LINE.**
+  `test_inverter.py`, `test_maintenance.py`, `test_peakguard.py` and
+  `test_watchdog.py` build a second inverter at 3000 W against A's 5000 W. The
+  only property those checks consume is that B's number is **unmistakably** not
+  A's, and the real pair is a **400 W** gap — narrower than `slew_w`, inside the
+  range where an off-by-one-unit bug and ordinary control arithmetic produce
+  indistinguishable numbers. Collapsing them onto the real values would buy
+  realism those checks do not use and cost them their separating power, which
+  is the defect `test_peakguard.py`'s own §10g precondition exists to prevent.
+  They are **illustrative, not B's rating, and no longer a placeholder for it**.
+* **Two consequences with numbers, recorded in `goodwe/NOTES.md` §1.1b for the
+  cards that own them.** At 94 % battery-to-AC a round trip is ≈ 88 %, so A
+  charging 3 kW while B discharges 3 kW burns ≈ **360 W continuously** with the
+  meter at zero — SAFETY-31 argues its threshold from *"a few watts"* and has no
+  figure. And **< 13 W night self-consumption per unit** (≈ 26 W for two,
+  ≈ 0.6 kWh/day), which nothing in this add-on accounts for anywhere.
+* **The site is asymmetric in opposite directions:** A = 5000 W / 15.36 kWh
+  nominal, B = 4600 W / 20.48 kWh — ~33 % more energy, ~8 % less power. No
+  stability implication (ARCH-01's ḡ = Σαᵢgᵢ is a convex combination), but a
+  full recalibration of B moves 33 % more energy and **MAINT-05's 12 h `drain`
+  phase timeout was derived on A**; it should be re-checked against B rather
+  than assumed to carry.
+
 **Every pack is recalibrated on its own schedule, and only one moves power at a
 time (MAINT-05).** §12's monthly cycle drains a pack to empty and refills it to
 true its coulomb counter. There was exactly one `Maintenance` state machine and
@@ -118,6 +741,284 @@ two power-moving phases on one grid connection pulling against each other.
   is loop and allocator territory. Pinned as a running check
   (`test_maintenance.py` part 12) so it cannot be forgotten.
 
+**`bms_soc_floor` describes a BATTERY, so at two packs it stops being one number
+(SAFETY-32).** The peak guard's energy backstop rests on two figures: the EMS
+floor `peak_soc_floor` (the depth a money-saving discharge may never reach) and
+`bms_soc_floor`, the percent **that pack's own BMS** cuts out at — register
+`0x0560`, read as 10 on the reference GW5000S-BP. Rule 8 refuses an EMS floor at
+or below the cut-out, because such a floor can never bind: the BMS wins and the
+status page reports a backstop that does not exist. With ONE cut-out for two
+packs of different models that rule graded the EMS floor against whichever
+battery happened to be written into the flat key, and a site with cut-outs of
+10 % and 30 % under `peak_soc_floor: 20` **started** — the guard would then
+command a forced discharge that pack B's BMS, not the operator's floor, is the
+thing that stops. Rule 8's own failure mode, reached through rule 8.
+
+* **`bms_soc_floor` becomes a per-entry roster key, and it is REQUIRED there.**
+  Nothing is inherited: an entry that omits it has no cut-out, does not borrow
+  the flat one, and is refused by name at startup. A per-entry *default* was
+  considered and declined — a default is one number for every pack, which is the
+  defect this card removes; `DECISIONS/SAFETY-32-per-pack-bms-floor.md` records
+  the decision and its migration cost. The flat key is unchanged and is now
+  documented as the single-inverter shape's own cut-out.
+* **Rule 8 grades EVERY unit and NAMES the one it refuses**, through a new
+  `unit_bms_floors_indexed()` that carries the **roster** index the value came
+  off. CFG-04 had just fixed a rule 5/6 bug of exactly this shape — a caps-list
+  index fed to a function that indexes the roster, so the message named the wrong
+  inverter — and this reader skips nothing, so there is no second list for an
+  index to desynchronise from. Graded on a roster whose offender is the SECOND
+  entry *and* on the same two numbers in the other order.
+* **The permission is answered PER PACK.** `Controller.pack_floor_soc` — the
+  emptiest measured pack — is untouched and is still what `decide()` grades;
+  what changed is the floor. `peakguard.pack_permissions()` answers one
+  `(name, reason)` per pack against that pack's own floor, and the floor-limited
+  notification now names the pack that stopped the site rather than "the
+  battery". At a roster of one the alarm is byte-for-byte what SAFETY-25 shipped.
+* **An unstated cut-out withholds rather than defaults.** `None`, not `0.0` —
+  `discharge_permitted()` already treats an unknown floor as no permission, so
+  the absence costs a shave and never a pack, including on `sim/inject.py`'s path
+  which does not run the startup gate.
+* ⚠️ **Stated rather than hidden:** under any config rule 8 accepts, the per-pack
+  *floor* reduces to `peak_soc_floor` for every pack — rule 8 makes it so. The
+  reduction is written for `unit_caps_indexed()`'s reason ("unreachable" is a
+  claim about rule ordering, not a property of a function) and is graded on both
+  sides: 1775 rule-8-valid `(peak_soc_floor, bms_soc_floor)` pairs answer the
+  option, and the pair rule 8 refuses answers the cut-out. `peak_soc_floor`
+  itself is still one number for the site, so the "deeper pack needlessly
+  withheld" half is filed as an open question, not closed.
+* **`tools/supervisor_shape_probe.py` re-run and repaired.** MUTATION.md habit 8:
+  a committed transcript is a check and it decays. The required key broke §C and
+  left §D printing PASS on a refusal about a *different* key. §D is now an
+  isolated counterfactual over an accepted, merged baseline, one key varied per
+  case, asserting the key **name** in the refusal — `all cases passed` on
+  `amd64-hassio-supervisor:2026.08.0`.
+* ⚠️ **SECOND FIX ROUND — the round-2 fix carried the defect it was written to
+  close, in its prose.** Two more rewrites survived a green 19-file suite on
+  `8501e05`: `binding_soc_floor()`'s `max(floors)` → `max(floors[-2:])` (+5
+  bytes) and the call site's `self.packs` → `self.packs[:2]` (+4 bytes). Both are
+  checks whose TEXT claimed more than their FIXTURE could reach — 12c2's only
+  counterfactual varied the **last** pack, which every window ending at the
+  roster's end follows, and all three 12g runs drove a **two**-pack roster, where
+  `[:2]` *is* the roster. **The general law, now stated in the file: a fixture of
+  N packs cannot separate two reductions that agree on N packs**, and the regress
+  does not terminate in a fixture — `[:1]` needed two packs, `[:2]` three, `[:3]`
+  four. So the reduction is now graded by a **length sweep** (78 simulated
+  rosters, lengths 1–12, deepest cut-out at every position, closing head and tail
+  windows of width 1–11 at once) plus a **computed family table** of fourteen
+  rewrites that goes red naming any member no roster kills; the call site is
+  graded by **three-pack runs** with the deep cut-out at index 0, 1 and 2, plus
+  an **exact structural pin** (the roster argument must unparse to `self.packs`)
+  for the slice widths no bounded roster can reach. Round 3's own battery found
+  `self.packs[:3]` / `[-3:]` surviving all six behavioural runs — the structural
+  pin is what closes them — and one row is recorded **NOT CAUGHT**: a reduction
+  over a window twelve packs wide, which needs a 13-pack roster to observe.
+  No shipped behaviour changed in this round; only what observes it.
+* **Twelve source mutations, eleven red, one argued survivor**, through
+  `tools/mutation_run.sh` (bytecode purged). The battery also found a real
+  weakness of its own: `_flat_bms_floor()` had the default in two places and each
+  covered for the other, so deleting either survived — masking, in three lines of
+  option reading. One defaulting line now.
+* ⚠️ **FIX ROUND — that battery was INCOMPLETE, and the review found what it
+  missed.** Neither of the two mutations below appears in the twelve rows above:
+  the ledger graded "the reduction dropped" and "the bare option handed over"
+  and never asked what happens when the reduction is simply the *wrong* one, or
+  when the roster handed to it is *sliced*. No shipped behaviour changed here;
+  two *checks* whose data could not reach the failure they named did. `max(floors)` → `min(floors)` in
+  `binding_soc_floor()` (zero byte delta) and `self.packs` → `self.packs[:1]` at
+  the `decide()` call site (+4 bytes) were each green across all 19 files. Both
+  survived for the same reason: **under any rule-8-valid config every pack's
+  `pack_floor_pct()` equals `peak_soc_floor`**, so `floors` is a list of
+  identical numbers and `max`, `min`, first and last are four spellings of one
+  answer — and the one check using a cut-out above the EMS floor ran on a roster
+  of ONE, where every reduction agrees. The second also walked through part 12g,
+  which asserted `"self.packs" in <the unparsed call site>`: a slice still
+  contains that substring, so the pin passed on the mutation that grades the
+  whole site against pack A. MUTATION.md habit 4 — a source-text test is a check
+  on how code is spelled, not on what it does.
+  * **New part 12c2** evaluates `binding_soc_floor()` on a roster whose per-pack
+    floors **all differ** — four simulated cut-outs of 30/25/40/35 %, every one
+    above `peak_soc_floor`, chosen so that `max` (40), `min` (25), first (30),
+    last (35) and the mean (32.5) are five different numbers and the two extremes
+    sit at *interior* roster positions. Two packs cannot separate those four;
+    four is the smallest roster that can. The precondition is its own check
+    (habit 1) and one pack — the last, neither deepest nor shallowest — is then
+    raised past the old maximum and the answer follows it (habit 7).
+  * **Part 12g is now behaviour, not source text.** Real `Controller.cycle()`s on
+    a two-pack roster, both packs at the same SoC, with the cut-outs as the only
+    thing varied: move the **non-first** pack's cut-out and the floor reaching
+    `decide()` moves 20 % → 35 %, with the site's verdict flipping from a sized
+    discharge to FLOOR-LIMITED. `self.packs[:1]` answers 20 % both times. Which
+    option key the floor comes from stays pinned on the source where it already
+    was, because that claim genuinely is about the code's shape.
+  * ⚠️ **Two MORE survivors, found by this round's own battery and recorded
+    rather than quietly repaired.** (a) The first cut of part 12g varied only
+    pack B's cut-out, so `self.packs[-1:]` — grade the site against the **last**
+    pack — agreed with the full roster on both runs and stayed green across all
+    19 files (+5 bytes). A two-run fixture pins one slice and not the other.
+    Part 12g now runs the **same pair of cut-outs in both orders**, so the
+    deeper one is on the second pack in one run and on the first in another and
+    the site floor is 35 % in both; no single-position slice passes all three
+    runs. (b) `binding_soc_floor()`'s empty-roster branch rewritten to
+    `return None` (−43 bytes) was also green — a defensive branch nothing in the
+    suite reached. Both directions of it are pinned now, with the note that it
+    cannot permit anything either way because `pack_floor_soc` is `None` at an
+    empty roster.
+
+* ⚠️ **THIRD FIX ROUND — the same family was alive at the SIBLING ARGUMENT of
+  the same call.** Rounds 2 and 3 hardened the FLOOR axis; `decide()` is handed
+  a second reduction over the same roster beside it, `soc=self.pack_floor_soc`,
+  and `peakguard.py`'s own docstring names the two as a pair. Three rewrites of
+  `Controller.pack_floor_soc` were green across all 19 files on `52380c0` and
+  again after the rebase onto `3934ad7`: `min(float(v) for v in vals)` →
+  `vals[:2]` (+4), `vals[-2:]` (+5) and `vals[:3]` (+4), while `[:1]`, `[-1:]`,
+  `[1:]`, `[:-1]`, `max()` and the mean were all red. **The suite's separating
+  power on the SoC axis stopped at exactly N=2** — the state the floor axis was
+  in before round 3. It changes a real answer: a three-pack roster at
+  50 / 60 / 11 % with the emptiest pack THIRD answers 11 % shipped and 50 %
+  mutated, so the site is graded for discharge PERMISSION against a pack 39
+  points fuller than the emptiest and spends a pack its own BMS stops. Round 3's
+  machinery transfers directly — new **part 12i**: six real `cycle()`s with the
+  emptiest pack at every position of a three-pack roster and both positions of a
+  two-pack one (the observable read off `PeakDecision.soc`, cut-outs held flat
+  so the floor axis cannot be what moved the answers); computed slice and
+  non-slice tables that go red naming any member nothing kills; a **length
+  sweep** of 78 real rosters, lengths 1–12, closing head and tail windows of
+  width 1–11 and recording width 12 as honestly unreached; a **none-guard
+  sweep** over the same 78; and **three exact structural pins** — the `vals`
+  comprehension must iterate the bare `self.inverters`, and both `any()` and
+  `min()` must reduce the whole `vals` — which close every slice width at every
+  roster length. No shipped behaviour changed; only what observes it.
+* ⚠️ **SPIKE-04: production is DEGENERATE on the floor axis, so the
+  differing-floor fixtures are the entire exposure.** Pack B is 4 × Dyness
+  DL5.0C, DoD 90 → floor 10 % — **FROM THE DATASHEET AND THE SERIAL; inverter B
+  does not exist and nothing about it is measured.** Pack A is DoD 90 → 10 % as
+  well, and that one *is* measured. Both packs therefore floor at the same value
+  in the field, `max(10, 10)` is 10 whatever it reduces, and a differing floor
+  exists **only in the fixtures**. That is the argument for keeping them, not for
+  simplifying them: anyone who collapses `A_PACK_FLOOR != B_PACK_FLOOR_SIM` to
+  one number deletes the only data this repository has that can see the
+  reduction at all, and part 12c2's precondition check goes red if they do. The
+  **SoC** axis has no such degeneracy — two batteries at the same state of
+  charge is a coincidence, not a configuration — which is what makes
+  `pack_floor_soc` the half of the pair that will be live from the day inverter
+  B is wired up.
+* ⚠️ **The FAMILY enumerated rather than the member closed, and it found four
+  more survivors in code this card never touched.** Every reduction over
+  `self.inverters` / `self.packs` in `Controller` was found from the AST and
+  mutated to a slice against the full suite. Eighteen were already graded
+  (`site_batt_w`, `site_rating_w`, `site_max_w`, `site_dev_bound`,
+  `site_circulating_w`, `inputs_ok`, `units`, `Controller.packs`, `maint_unit`,
+  the maintenance-due minimum, the store-migration roster, `validate_unit_ranges`
+  and the round-2/3 sites). **Four were not, and three of them are SAFETY-30's,
+  all `any(i.sign_wd.tripped for i in self.inverters)`** — `cycle()`'s
+  stale-input hold, `publish()`'s status vocabulary and `status_payload()`'s
+  banner — each +4 bytes and green across all 19 files, for the reason every
+  blocker on this card was invisible: **the only fixture that reached them was a
+  roster of ONE, where `self.inverters[:1]` IS `self.inverters`.** The first has
+  teeth: a latched unit must take the roster past that hold or its `failsafe`
+  SET stops being re-filed the moment a poll is missed, which is main.py's own
+  sentence for it. New **test_watchdog.py part 8** grades all three with the
+  latch at EACH position plus a no-latch counterfactual, and new **part 12j**
+  pins all 26 roster comprehensions in `Controller` to iterating the roster
+  whole — so a reduction added over a slice anywhere in the class is red on the
+  line it is written, with no fixture required. Two rows are reported open
+  rather than closed: `_grade_store_migration()`'s second disjunct (now red on
+  12j, and argued to be an equivalent mutant because a unit tripped at startup
+  implies its namespaced key is set) and `cycle()`'s undeliverable-unit **log
+  line**, where `sorted(...)[:1]` (+4 bytes) is still green — it truncates names
+  in one event message; the refusal itself is a different expression and is
+  graded, so the site still stops.
+* ⚠️ **FOURTH FIX ROUND — the same family one MODULE over, and the pin widened
+  until it discovers its own scope.** Round 4 enumerated the family and closed
+  it inside the `Controller` class; the review found four more survivors
+  immediately, in **validate.py**, on a 19/19 green suite: `min(caps)` →
+  `min(caps[:1])` (+4) and `→ min(caps[-1:])` (+5) at `:779`, the caps
+  comprehension over `caps_ix[:1]` (+4) at `:778`, and
+  `min(caps_ix[-1:], key=…)` (+5) at `:893`. **None is an equivalent mutant.**
+  With `max_w: 5000` on inverter-a beside `2000` on inverter-b and
+  `sign_disagree_w: 3000`, the shipped validator refuses — *"the SAFETY-02
+  sign-disagreement watchdog can never fire"* — and all four **accept**: the
+  site starts with a watchdog reporting `armed` that cannot trip on pack B.
+  Rule 5's own failure mode reached through rule 5; rule 6 loses its refusal the
+  same way. **No shipped behaviour changed by the pin; what changed is that a
+  hand-written scope stopped being trusted.**
+  * **`test_peakguard.py` part 12j now parses every `.py` under `app/`** — no
+    module is named in the check — and finds the roster by transitive closure
+    from **one seed**, the `inverters` option key: through returns, through
+    lists **accumulated in a loop over a roster** (which is what `caps`,
+    `roster` and `problems` are, and what round 4's rule could not express),
+    through attributes and properties, and **through call arguments**, which is
+    how it walks into `peakguard`, `arbiter`, `allocator`, `circulation`,
+    `maintenance` and `store` without being told they exist. A slice of a roster
+    stays a roster so a mutation cannot cut the taint; an index is one unit and
+    does not. **183 reductions across 9 modules** out of 23 files parsed — `main.py` 96,
+    `allocator.py` 24, `validate.py` 19, `arbiter.py` 14, `circulation.py` 10,
+    `maintenance.py` 10, `peakguard.py` 4, `inverter.py` 3, `store.py` 3.
+  * **The hand-written module list would have been wrong in BOTH directions.**
+    It named `watchdog.py`, which reduces over no roster at all — SAFETY-30's
+    sign watchdogs are strictly per-unit — and omitted `maintenance.py` and
+    `store.py`, which both do. A vacuous claim about one module and no claim
+    about two others.
+  * **The pin rediscovers all four blockers without being told where to look,**
+    and finds a fifth beside them (`validate.py:783`, rule 5's message) that no
+    review round named. Its counterfactual runs at two depths: every enumerated
+    site's own expression mutated with each of the four cuts this card has been
+    defeated by (732 spellings, all reported), and `[:1]` written into
+    `app/validate.py` at each blocker position with the **whole** analysis
+    re-run over the mutated source — a sliced site required at that exact line,
+    where the clean package reports none.
+  * **And the behavioural half, because a shape pin grades an identity and never
+    a meaning.** `test_validate.py` grows a **roster SET** for the three rules
+    that reduce over `unit_caps_indexed()` — widths 2, 3, 4, 5 with the one
+    small cap at every position, 42 runs of the real validator — plus a
+    **computed family table** of twelve candidate reductions each compared with
+    what the shipped validator actually said on the same roster. Only `min`
+    agrees everywhere; a member no roster kills is printed as a named survivor.
+  * ⚠️ **A THIRD RULE WAS READING THE FLAT `max_w`, AND IT IS SAFETY-30's** —
+    found by reading, **not** by the pin, which is the shape of what the pin
+    cannot see. `unit_sign_disagree_w` was graded against
+    `_number(opts, "max_w", 2000.0)` three lines under a branch that had already
+    stopped doing that. **Both directions were measured:** two 2000 W units
+    beside a leftover `max_w: 5000` and `unit_sign_disagree_w: 3000` produced
+    **zero problems** — the site started with a per-unit watchdog that could not
+    trip on either unit — and two 5000 W units with no flat key were **refused**
+    against a 2000 W default the operator never wrote. It takes the weakest
+    unit's own cap now and names that unit; at a roster of one it is the same
+    comparison, boundary and sentence it always was.
+  * ⚠️ **What the pin cannot see, with sizes**, in
+    `DECISIONS/SAFETY-32-per-pack-bms-floor.md` §4d: semantics (`min` vs `max`
+    is a zero-byte edit); direct index sites that are not reductions; a
+    subscript by a *variable* (`weights[u]` is why); a slice through an
+    intermediate call; anything outside `app/`, including `sim/inject.py`; and
+    the taint's own seam at `*args` and unresolvable receivers, where everything
+    downstream goes **unenumerated rather than reported unreachable**.
+    `cycle()`'s undeliverable-unit log line is still green at +4 bytes and still
+    filed open, unchanged from round 4.
+  * **`tools/supervisor_shape_probe.py` re-run again (2026-09-05, 2026.08.0).**
+    The rebase onto `67e649a` merged SPIKE-04a's `max_w: 4600` into the same
+    §C/§D blocks this card had rewritten, and a transcript stitched by hand out
+    of two runs is not a measurement. `all cases passed`, exit 0, with B's
+    rating reading 4600 — its **datasheet** figure, still not a measurement of
+    any unit.
+  * ⚠️ **THE SWEEP, AND THE NUMBER THAT MUST NOT BE QUOTED ALONE.** All 183
+    sites mutated to `[:1]`, one at a time, against the full 19-file suite in
+    `goodwe-addon-ci` (`:ro`, `-B`, fresh rsync per mutant, 0 `.pyc` before and
+    after): **183/183 RED** — which is tautological on its own, because the pin
+    makes every slice red. The 51 whose first red was `test_peakguard.py` were
+    re-run with the pin **neutralised**: **145 of 183 have a behavioural fixture
+    that separates them from a slice of themselves; 38 have only the structural
+    claim.** All 38 are listed by site, with what a `[:1]` there would cost, in
+    §4d and in `test_peakguard.py` part 12j — 15 of them are rows and counts on
+    the operator's page, 3 are `len(targets)` arithmetic beside a write path
+    that IS graded, 6 are allocator internals ALLOC-01's fixtures reach but not
+    with enough units to separate. **None of the 38 is closed behaviourally by
+    this card, and none is counted as covered.**
+
+⚠️ **No measurement of inverter B appears anywhere in this change.** It does not
+exist yet. Every second-pack figure — in fixtures, in the probe, in
+config.yaml's commented example — is **simulated and labelled**; only inverter
+A's 10 % is read off hardware.
+
 **At two inverters the sign watchdog stops comparing one unit against the whole
 site meter, and becomes two checks instead of one (SAFETY-30).**
 `disagrees(commanded_w, grid_w, ...)` compared the command **this controller put

goodwe_controller/DECISIONS/SAFETY-13-bounding-the-output-freeze.md

@@ -0,0 +1,396 @@
+# SAFETY-13 — the output freeze gets an exit, and only where it cannot end on its own
+
+**Status:** decided and implemented on branch `SAFETY-13`, off `release/1.0` @ `c8dcb38`.
+**Card:** SAFETY-13 — *"Bound the no-start-while-saturated output block"*
+([Trello](https://trello.com/c/uZjmuF7B)).
+**Nothing here reached the inverter.** Every figure below is from the pure control
+law run in a container against a plant model, on this branch and on a pristine
+`c8dcb38` for the before-figures. No rig, no ESP32, no Home Assistant.
+
+---
+
+## 0. The four things a reader should take away
+
+1. **The card's headline case is real, and the route to it is not the obvious
+   one.** The block does not engage on the way down into an export; the slew
+   limit moves the command off zero before the counter reaches 3. It engages
+   from the **deadband** — a site resting at its target with another writer on
+   the bus, counting saturated cycles while nothing is wrong — and 0 W is then a
+   fixed point. §2.
+2. **`prev_w == 0` is not a special case, so the fix is not one either.** The
+   same run pins at −800 W against its own integrator standing at −2388 W, at a
+   non-zero `prev_w`, with
+   the same absence of an exit. Zero is only the instance where the pinned
+   magnitude is the whole of what the battery could have done. §3.
+3. **The decision is not "how long", it is "which".** A divergence a *limit*
+   could have produced clears itself and gets no exit — `release/1.0` unchanged.
+   A divergence a limit could not have produced may not, and gets one. The
+   predicate is physical, not statistical — and it is **not** a second-writer
+   detector; §4.1 and §8 say what it can and cannot tell apart.
+4. **Releasing the output freeze does not unfreeze the loop**, and that is what
+   makes the release bounded rather than merely different. §6.
+5. **The bound comes from the SLOWER half of a two-sided measurement, and the
+   first version of this branch took the faster half.** §8 is the correction and
+   the measurement behind it; it is the reason `SETTLE_CYCLES` is 12 and not 9.
+
+---
+
+## 1. What was there, in the terms the code uses
+
+`control.py`, in `compute()`, after the clamp and the slew limit:
+
+```python
+if frozen:
+    target = min(target, prev_w) if prev_w > 0 else max(target, prev_w)
+    reason = "saturated-freeze"
+```
+
+"Magnitude may fall, never rise." At `prev_w == 0` the magnitude is zero and
+`max(target, 0)` forbids any negative command, so a charge cannot **start**.
+
+The reason is written in the file and it is a good one: `frozen` means the
+inverter's reported power has diverged from the command by more than
+`saturation_w` for `saturation_cycles` consecutive cycles, and at a command of
+zero that means the actuator is producing power nobody in this add-on asked for.
+Starting to push the other way into it is the configuration §1.5 of the
+specification rules out — *"any configuration in which two writers can reach one
+actuator"*.
+
+**The defect is that it has no end.** Not the error growing, not the integrator
+moving, not time. `sat_count` stops rising at its cap and the state is a fixed
+point.
+
+---
+
+## 2. Reproducing it — and correcting the route
+
+Driven at the live install's shape: `max_w 5000`, `slew_w 400`,
+`target_grid_w -10`, `saturation_w 500`, `saturation_cycles 3`, `gain 0.6`.
+Another writer holds the pack at **+700 W** whatever is commanded.
+
+**The route that does NOT reach it.** Start at `prev_w = 0` with 2 kW of export
+already standing. On `c8dcb38` the loop moves off zero at the slew limit before
+the counter reaches 3 — commands −400, −800 — so by the time `frozen` is true
+`prev_w` is −800 and the block that gets applied is `max(target, −800)`. The
+site charges at 800 W, not 0 W, for as long as the run lasts.
+
+**The route that does.** The site is *resting*. `grid == target_grid_w`, so the
+loop is in its deadband and the command is 0 — and `saturated_now` is computed
+**before** the deadband branch, so the counter climbs anyway. Three cycles later
+the loop is frozen at `prev_w == 0` with nothing wrong. Then the export arrives:
+
+| cycle | grid | actual | prev | command | integrator | sat | reason |
+|---|---|---|---|---|---|---|---|
+| 0–1 | −10 | +700 | 0 | 0 | 0 | 1–2 | `deadband` |
+| 2–5 | −10 | +700 | 0 | **0** | 0 | 3–6 | `saturated-freeze` |
+| 6 | −2000 | +700 | 0 | **0** | −1194 | 7 | `saturated-freeze` |
+| 7… | −2000 | +700 | 0 | **0** | −1194 | 8→10 | `saturated-freeze` |
+
+On `c8dcb38` the command is `0.0` on **every** cycle from there on. The
+integrator has moved to −1194 W and stopped (its own freeze holds it), the site
+exports 2 kW, and the battery is idle until the other writer leaves.
+
+That is the card's sentence — *"the site can sit exporting 2 kW with an idle
+battery indefinitely"* — reproduced, with the route corrected: it is entered
+from the **deadband**, not from a correction that ran out of room.
+
+---
+
+## 3. …and `prev_w == 0` is not where it stops
+
+The same tuning, same writer, but the loop starts from zero with the export
+already standing (the route from §2 that "does not reach it"):
+
+| | `c8dcb38` |
+|---|---|
+| command after the freeze engages | **−800 W**, on every cycle |
+| the loop's integrator, frozen | −2388 W |
+| what ends it | nothing |
+
+So the missing exit is a property of the **output freeze**, not of the zero
+case. `prev_w == 0` is the instance where the pinned magnitude happens to be
+zero. A rule written for zero alone would have left −800 W exactly as unbounded
+as it found it — which is why the change below is written against the freeze and
+not against a special case of it.
+
+**And this is the half that escalates at two inverters.** `actual_w` is
+`site_batt_w`, the SUM (ALLOC-01, DEV-02), so the comparison is a site command
+against two units' power. One unit still moving after the other has stopped is
+enough to put the site into the freeze with no external actor at all.
+
+⚠️ **What that claim is and is not.** The escalation is stated from the code —
+`prev_w` is `self.target`, the site total, and `actual_w` is the site sum — and
+from the single-unit runs above. **It is not measured on two inverters.**
+Inverter B does not physically exist (`NOTES.md` §1.1b: on paper, from datasheet
+and serial), and `sim/plantsim.py:216` `INVERTER_B` is `INVERTER_A` copied with
+`measured=False`. Any two-inverter number would be two copies of A.
+
+---
+
+## 4. The decision: which freezes get an exit, not how long the block lasts
+
+Three answers were on the table, and the card named them: lift after N frozen
+cycles, exempt above some export magnitude, or keep it unbounded and write down
+the cost.
+
+**A plain cycle bound was rejected**, because it bounds the wrong thing. The
+freeze is right to be permanent in one case and cannot be permanent in the
+other, and a single N treats them alike:
+
+| the inverter is… | can the freeze clear itself? |
+|---|---|
+| doing **less** than the command, in the command's own direction — a cold pack, a curtailment, an export cap, the plant still ramping | **Yes.** The command is pinned at something the inverter can reach, so it catches up, `saturated_now` goes false, and the freeze ends. Asking for more would achieve nothing anyway. |
+| doing something **outside** what the command can explain — overshooting it, or the opposite sign | **No.** Clearing the freeze requires the inverter to track *our* command, and the other writer is precisely what stops that. |
+
+**An export-magnitude exemption was rejected** for a narrower reason: it makes
+the block's end depend on how big the other actor's disturbance happens to be,
+which is not a property of the thing the block is about.
+
+So the rule implemented is:
+
+> The output freeze applies as before, **unless** the inverter's reported power
+> cannot be explained by the command not being met **and** the divergence has
+> outlasted the plant that would otherwise have explained it.
+
+### 4.1 The predicate is physical
+
+`unasked_power(prev_w, actual_w, saturation_w)`. A limit can only make the
+inverter do **less** than the command, in the command's own direction. It cannot
+make it overshoot the command and it cannot make it produce the opposite sign.
+So everything a limit can produce lies in the closed interval spanned by `0` and
+`prev_w`, widened by `saturation_w` for noise, ramp lag and idle draw.
+
+⚠️ **What it does NOT establish is that anything outside was put there by
+something else.** The first version of this branch said exactly that, in the
+docstring, in `control.py` and in DOCS.md, and it is false: the predicate
+compares against **one cycle's** command while the pack carries every command
+before it, so our own coast-down through zero lands outside our own interval.
+§8 measures it. What the predicate guarantees is only its own first sentence —
+*this cycle's command does not account for this cycle's reading* — and the time
+bound below is what turns that into a reason to act.
+
+| prev | actual | interval | verdict |
+|---|---|---|---|
+| +2000 | +700 | [0, 2000] | a limit |
+| −5000 | −700 | [−5000, 0] | a limit |
+| 0 | +700 | [−500, +500] | **unasked** |
+| −800 | +700 | [−1300, +500] | **unasked** |
+
+⚠️ **At `prev_w == 0` this predicate and the saturation detector are the same
+test** — asserted in `test_control.py` over 801 readings. That is not a
+coincidence to tidy away: with nothing commanded there is no interval left for a
+limit to live in, which is exactly why the zero case is the one that strands.
+
+⚠️ **It is not a detector and nothing alarms on it.** A stale, wrong-signed or
+noisy reading lands outside the interval too. All it decides is whether the
+freeze gets an exit; being wrong about it costs a bounded command (§6).
+SAFETY-30's `unit_sign_disagree_w` is the thing that alarms on sign, and it is
+deliberately a different test with a different threshold.
+
+### 4.2 The bound, and which half of the measurement it comes from
+
+`SETTLE_CYCLES = ceil(PLANT_SETTLE_DOWN_S / LOOP_TICK_S)` = **12**.
+
+⚠️ **`PLANT_SETTLE_DOWN_S` is new, and adding it is the point rather than a
+cost.** `NOTES.md` §5.10 did not measure *a* settling time; it measured the same
+1.78 kW step in **both directions** — "Up: ~18 s from step to deadband. Down:
+~23 s from a −1784 W export excursion" (`NOTES.md:1550`). So the plant's
+settling time is a **pair**, and which half is the safe one depends on which way
+being wrong hurts:
+
+| the bound | the question | the safe half | why |
+|---|---|---|---|
+| SAFETY-39's `SLEW_RAIL_FRAC` | may this configuration be **refused**? | **18 s**, the shorter | a looser bound refuses fewer working configurations |
+| this one | may the plant still be the **explanation**? | **23 s**, the longer | a shorter bound stops believing the plant too early, and then it accuses |
+
+The first version of this branch reused `PLANT_SETTLE_S` and got 9 — three
+cycles short of the plant's own measured down-ramp, on the side that produces a
+false positive. §8 is the measurement and the correction.
+
+⚠️ **It is no longer the reciprocal of `SLEW_RAIL_FRAC`, and it never should
+have been read as one.** The two were equal only while both were being derived
+from the same half of the pair, and that coincidence read as a derivation. They
+are 9 and 12 now; `test_control.py` asserts the inequality so they cannot be
+quietly re-fused.
+
+⚠️ **It inherits SAFETY-39's caveat about `LOOP_TICK_S`, in the opposite
+direction.** A meter **slower** than 2 s makes 12 cycles cover more than 23 s, so
+the freeze holds longer than the plant needs: that costs energy, never safety. A
+meter **faster** makes them cover less, so the freeze can release while the
+plant is still moving — bounded by §6 rather than by luck.
+
+**`_SAT_COUNT_CAP` moved with it, from 10 to 13**, because it is written as
+`SETTLE_CYCLES + 1` — a counter capped below the longest bound read from it
+would silently delete the exit. That has a consequence worth stating on its own:
+`config.yaml` accepts `saturation_cycles` as `int(1,10)`, so at the old bound of
+9 a legal setting could sit **above** the exit and delete the block. At 12 the
+whole accepted range is strictly below the bound, and the degenerate
+configuration this branch used to document no longer exists. §7.
+
+---
+
+## 5. What actually changed, graded against `release/1.0`
+
+`test_control.py`'s sweep still compares this law against a transcription of
+`release/1.0` — the transcription was **not** taught the new rule, because an
+oracle taught the change compares the law against itself. What changed is the
+assertion: every case must be identical, or be a release with both of its
+conditions true, or differ **in the saturation counter alone**.
+
+⚠️ **The sweep had to be widened to keep grading anything.** Its `sat_count`
+fixtures ran to 9; with the bound at 12 the counter never reached the exit and
+every release silently vanished from the table, which is what the assertion on
+the count caught. It runs to 12 now, at 3780 cases.
+
+| | cases |
+|---|---|
+| total | 3780 |
+| **bit-identical to `release/1.0`** | **3267** |
+| releases | 432 |
+| …of those, reason-only (the freeze was not binding) | 405 |
+| …of those, **the command changes** | **27** |
+| differ in the **saturation counter alone** | 81 |
+
+All 27 command changes are at `prev_w == 0`, all with `release/1.0` commanding
+exactly `0.0 W`, and every new command is **negative** — a charge start that was
+refused.
+
+⚠️ **The 81 are the counter's ceiling moving, and they reach nothing.**
+`_SAT_COUNT_CAP` went from 10 to 13 with the bound, so above `release/1.0`'s own
+ceiling the two counters differ. Nothing else may differ in those cases, and the
+sweep asserts that: `frozen` is `sat_count >= saturation_cycles`, `config.yaml`
+accepts that at most 10, and no other line in `compute()` reads the counter's
+value — so a counter reading 13 instead of 10 cannot change what is commanded.
+The 81 all sit at an `sc` above 10, which is a state `release/1.0` could never
+hold at all.
+
+The behaviour after the fix, on §2's run: the command holds at 0 W through
+`sat_count` 3–11, releases on the **twelfth** saturated cycle, and walks
+0 → −400 → −800 → **−1190 W**, where it stops — the same settling point as at
+the old bound, three cycles later.
+
+The genuine-limit case, driven for 30 cycles with the inverter curtailed to
+±1000 W against a 4 kW import: `freeze-released` never appears and the command
+stays pinned at +2400 W. Unchanged, deliberately.
+
+---
+
+## 6. Why the release cannot become windup (the card's fourth criterion)
+
+**The integrator freeze is not lifted with the output freeze.** The command is
+derived from `i_w`, then clamped, then slew-limited from `prev_w` — so a
+released cycle can only move the command *toward* an accumulator that stopped
+accumulating when the freeze engaged, by at most one slew step, and never past
+it. `test_control.py` sweeps 107 625 states, of which **67 500 release**: no
+released case leaves the interval between the previous command and the frozen
+integrator, and none moves further than one slew step.
+
+⚠️ **107 625 was previously reported as the number of released states. It is
+the number of states swept**, and the assertion only ever graded the subset that
+released. Both numbers are counted and printed now.
+
+On §2's run that shows up as the settling point: **−1190 W against a frozen
+integrator of −1194 W**, not the 5000 W rail. The tech lead's note on SAFETY-04
+— that the carried `i_w` and `release/1.0`'s recomputed value land on the same
+slew-limited command — is preserved: the `i_w=None` path is still graded against
+the transcription, cycle for cycle, everywhere except the 432 releases.
+
+⚠️ **The first form of this check was wrong and the sweep said so**, which is
+left in the test file. It asserted `|target| <= |i_w|` on a released cycle and
+produced `prev −5000, i_w −3000, target −4600`: the command was walking back
+from −5000 toward the integrator and had not arrived. It was moving the right
+way and the assertion still failed, because "never exceeds the integrator" is
+not what no-windup means here.
+
+---
+
+## 7. What this does NOT buy, said plainly
+
+**The site still does not reach its target while another writer is on the bus.**
+It settles at the frozen integrator, not at the meter's target. What the exit
+buys is that the battery stops being *idle* while the site exports; it does not
+buy correct regulation against an actuator somebody else is also writing to, and
+nothing in a rules engine can. A standing grid error with a second writer
+present is the symptom of a configuration this add-on refuses to support.
+
+**`freeze-released` is a place to start looking, not a finding.** It says the
+divergence outlasted the plant's own measured settling time, and that is all it
+says — §8. DOCS.md now tells the operator the innocent causes first (a large
+load or PV swing, a plant slower than the one that was measured) and the second
+writer only when the state **stands**. It is carried on `Decision.reason`, which
+nothing after the freeze overwrites. No new alarm was added: SAFETY-41 removed
+one that narrated normal anti-windup, and this state is not yet known to be
+worth waking anybody for.
+
+**No accepted configuration removes the block any more.** `config.yaml` accepts
+`saturation_cycles` as `int(1,10)`; the bound is 12, so every accepted value is
+strictly below it and the freeze always engages before its exit is due. This
+paragraph used to say the opposite — at a bound of 9, settings of 9 and 10
+deleted the block silently and the branch documented that as a known
+consequence. Moving the bound closed it by construction. `test_control.py` pins
+it against `config.yaml`'s own schema line rather than a transcription of it.
+
+**Nothing was measured on two inverters.** See the warning in §3.
+
+---
+
+## 8. ⚠️ ROUND 2: the bound was derived from the wrong half, and it accused
+
+**What was wrong.** `SETTLE_CYCLES` was `ceil(PLANT_SETTLE_S / LOOP_TICK_S)` = 9.
+`PLANT_SETTLE_S` is 18 s, the **up**-ramp of `NOTES.md` §5.10's kettle step;
+the same measurement recorded ~23 s coming back **down** (`NOTES.md:1550`).
+SAFETY-39 takes 18 correctly — its bound is a refusal, and the looser number
+refuses less. This bound asks the opposite question, and the looser number stops
+believing the plant three cycles too early.
+
+**Why that is not a tuning quibble.** The predicate has no memory. `prev_w` is
+one cycle's command; the pack carries every command before it. A command that
+falls **through zero** — the ordinary end of a load or PV step — leaves the pack
+coasting in the old direction, so the reading has the sign the command *used* to
+have and lands outside the interval spanned by 0 and the new `prev_w`.
+`unasked_power()` calls that "unasked". With the bound three cycles short of the
+plant's own down-ramp, the counter reaches it while the coast-down is still
+going, and the law emits `freeze-released` on **one inverter with nothing else
+on the bus.**
+
+**Measured, in the container, N = 1.** One `compute()`, one plant model, one
+command; no second writer anywhere in the harness. The plant is a first-order
+lag whose two time constants come from the two measured settling times
+(tau = t/3, since a first-order step is 95 % done at 3 tau) with
+`sim/plantsim.py`'s measured 800 W/s ramp cap. It is a **model**, and it is
+labelled one wherever it is used.
+
+| | bound 9 | bound 12 |
+|---|---|---|
+| 1280 closed-loop scenarios (a grid of plant pairs, slews, `saturation_cycles`, load steps) | **113 fire** | **24 fire** |
+| 272 load-step pairs at the measured 18 s / 23 s plant, `slew_w 400` | **62 fire** | **2 fire** |
+
+The single case now pinned in `test_control.py`: a 4 kW export falling to
+2.5 kW. At cycle 34 the command is −310 W, the pack is still at −1343.4 W
+coasting down from −4860 W a few cycles earlier, `unasked_power(−310, −1343.4,
+500)` is True, `sat_count` is 9, and the law says `freeze-released`. At 12 the
+same run never releases.
+
+**What the fix does not fix.** The bound makes the false positive rare on *the
+plant that was measured*. It cannot make it impossible, because it is a
+measurement and the plant can be slower than the measurement. Same sweep, bound
+held at 12, lengthening only the plant's down-ramp: 8 of 320 scenarios at the
+measured 23 s, 59 of 320 at 34 s, 268 of 320 at 50 s. That residual is why the
+three statements below were corrected rather than merely re-numbered.
+
+**Three shipped statements were falsified by this and are now rewritten:**
+
+1. `unasked_power()`'s docstring — *"Anything outside that interval was put
+   there by something other than this loop."* It was our own power. The
+   docstring now says what the predicate does guarantee (this cycle's command
+   does not account for this cycle's reading) and states the coast-down as its
+   known blind spot.
+2. `control.py`, in `compute()` — *"SO THE BOUND BELONGS TO (b) AND ONLY TO
+   (b)"*. It fired in case (a). The comment now says the bound is a reason to
+   stop believing (a), not a proof of (b), and that the release is written to be
+   survivable when the inference is wrong.
+3. **DOCS.md — *"If you see `freeze-released` in the action log, look for the
+   second writer."*** This is the one that reaches a person, and on a
+   single-inverter install it sent them hunting something that does not exist.
+   Replaced by a section that gives the innocent causes first and the second
+   writer only when the state stands.

goodwe_controller/DECISIONS/SAFETY-32-per-pack-bms-floor.md

@@ -0,0 +1,816 @@
+# SAFETY-32 — `bms_soc_floor` per pack, and the two judgement calls it left open
+
+**Status:** decided and implemented on branch `SAFETY-32`.
+**Card:** SAFETY-32 — *"One `bms_soc_floor` for two packs grades the shallower
+pack against the deeper one's cut-out"*, scoped by the card's own PM PROOFREAD
+to its **third** bullet only. Bullets 1 (aggregate anti-windup) and 2 (per-instance
+`achievable_w`) were verified as already shipped by DEV-02 and CFG-04 and were
+**not** touched — `main.py`'s `actual_w=self.site_batt_w` comment is the record
+of why the first of those must stay site-level, and it still reads as written.
+
+---
+
+## 1. The defect, stated in the terms the code uses
+
+`bms_soc_floor` **describes a battery**: it is the percent that pack's own BMS
+cuts out at, register `0x0560` on the reference GW5000S-BP, read as 10. It was a
+flat option because there was one pack.
+
+`peak_soc_floor` **describes the site's policy**: the depth a money-saving
+discharge may never reach. Rule 8 refuses `peak_soc_floor <= bms_soc_floor`,
+because such a floor can never bind — the BMS wins and the status page reports a
+backstop that does not exist.
+
+At two packs of different models the two cut-outs differ, and one number for both
+is wrong **in the direction that empties a pack**: with cut-outs of 10 % and 30 %
+and `peak_soc_floor: 20`, the add-on **started**, and the guard would command a
+forced discharge that pack B's *BMS* — not the operator's floor — is the thing
+that stops. That is rule 8's own failure mode, reached through rule 8.
+
+---
+
+## 2. DECISION 1 — required per entry, not defaulted from `PEAK_OPTION_DEFAULTS`
+
+The card left this open and asked for the reason to be recorded.
+
+**Decided: REQUIRED of every roster entry**, in `config.yaml`'s schema
+(`bms_soc_floor: int(0,50)`, no trailing `?`) and in `validate.py` rule 8, which
+refuses a missing one **by name**.
+
+The reason is that a default here is not a convenience, it is **this card's own
+defect wearing a different hat**. A default is one number applied to every pack,
+which is exactly what the flat key was. An add-on that answers "10 %" for a pack
+nobody has told it about has invented a property of somebody's battery, and the
+failure mode of the invention is the one this card exists to remove — the
+shallower pack protected by a floor that belongs to the deeper one. CFG-03's
+rule ("defaults live in exactly one place") points the same way: the one mirror
+`PEAK_OPTION_DEFAULTS["bms_soc_floor"]` is the default for the **flat** key, i.e.
+for the single-inverter shape, and reusing it per entry would make one dict the
+default in two shapes with two meanings.
+
+It is also the treatment `max_w` already gets, for the same reason and by the
+same argument (`inverter.py`'s `build_roster()` docstring): the per-unit numbers
+that describe hardware are required, and the per-unit *sensors* are optional
+because an absent sensor is a real state.
+
+**The cost is stated rather than hidden.** This is a schema change: a roster
+config written before this branch is refused by the Supervisor until each entry
+gains the key, and every roster fixture in the suite needed it. Nothing in
+production carries a roster today — `inverters:` ships `[]` and the second
+inverter is ~8 days out — so the migration is paid by fixtures and by whoever
+writes the first real roster, at a startup refusal that names the entry.
+
+**What is NOT inherited.** An entry that omits the key does not borrow the flat
+one. `Inverter.bms_soc_floor` is then `None`, `peakguard.pack_floor_pct()`
+answers `None`, and `discharge_permitted()` already treats an unknown floor as
+**no permission** — so even in the window before rule 8 runs (e.g. `sim/inject.py`,
+which does not run the startup gate) the absence costs a shave and never a pack.
+`0.0` was rejected explicitly: it is the most permissive value the key has.
+
+## 3. DECISION 2 — the site verdict is the MAXIMUM of the packs' own floors
+
+`Controller.pack_floor_soc` — the **minimum** measured SoC, the emptiest pack —
+**is unchanged**, exactly as the card instructed. What changed is the floor it is
+graded against. `peakguard.binding_soc_floor()` reduces the roster's per-pack
+floors, each of them `max(peak_soc_floor, that pack's own cut-out)`, with a
+`max()`. The two reductions pair: a minimum SoC against a maximum floor is the
+conservative combination, and both move the verdict towards refusing a shave and
+away from spending a pack. `min(soc) <= max(floor)` is implied by "some pack is
+at or below its own floor", so the site verdict is never more permissive than
+grading each pack separately would be. The converse is not true and is not
+claimed — a site can be refused while every pack individually has headroom, which
+costs a shave.
+
+### 3a. ⚠️ FIX ROUND — the reduction was written and argued, and NOT GRADED
+
+PR #48 was rejected because the argument in §4 below justified *writing* the
+reduction and was then not carried into a check. Neither of the two mutations
+below appears anywhere in §6's twelve-row battery: it graded *"the reduction
+dropped"* and *"the bare option handed over"*, and never asked what happens when
+the reduction is the **wrong one**, or when the roster handed to it is
+**sliced**. Both were applied to `app/` by the reviewer and **all 19 files
+stayed green**:
+
+| mutation | Δ | why it survived |
+|---|---|---|
+| `binding_soc_floor()`: `max(floors)` → `min(floors)` | **0 bytes** | every roster in the suite was rule-8-valid or one pack long, so `floors` held **identical numbers** and `max`/`min`/first/last were four spellings of one answer |
+| the `decide()` call site: `self.packs` → `self.packs[:1]` | **+4 bytes** | part 12g asserted `"self.packs" in <the unparsed expression>` — and `self.packs[:1]` **contains that substring** |
+
+The zero-byte one was proved to have actually run rather than assumed:
+`dis.get_instructions` showed the `LOAD_GLOBAL`s as `[float, pack_floor_pct,
+any, min]`, and `binding_soc_floor([Pack("a",50,10), Pack("b",50,35)], 20.0)`
+returned `20.0` where the shipped code returns `35.0`.
+
+**The common cause is this repository's recurring defect** — a check whose DATA
+cannot reach the failure it names. The one check that used a cut-out **above**
+the EMS floor (12c's `_n1_deep`) ran on a roster of **ONE**, where every possible
+reduction agrees. So no check in the suite ever evaluated
+`binding_soc_floor()` on two packs whose floors **differ**.
+
+**And the rule-8 degeneracy is not a defence, by §4's own words.** If
+"unreachable is a claim about today's rule ordering, not a property of this
+function, and `validate_startup_config()` is also `sim/inject.py`'s entry point"
+is enough to *write* the reduction, it is enough to *grade* it. Through
+`sim/inject.py`, which does not run rule 8 at all, `min(floors)` lets the guard
+command a forced discharge to 20 % on a pack whose BMS cuts out at 35 %.
+
+**What was added — no shipped behaviour changed, only what observes it:**
+
+* **`test_peakguard.py` part 12c2** evaluates `binding_soc_floor()` on a roster
+  whose per-pack floors **all differ**. Four **simulated** cut-outs —
+  `30, 25, 40, 35` %, every one strictly above `peak_soc_floor: 20`, so
+  `pack_floor_pct()` selects the cut-out for each and `floors` *is* that tuple in
+  that order. The four candidate reductions are then four different numbers:
+
+      max   = 40   <- the shipped answer
+      min   = 25
+      first = 30   <- "grade the site against pack A", inside the function
+      last  = 35
+      mean  = 32.5
+
+  The extremes sit at **interior** roster positions (index 2 is the max, index 1
+  the min). A two-pack roster structurally cannot separate these — there `max`
+  and `last` coincide and so do `min` and `first` — and neither can three. Four
+  is the smallest roster that separates all four. The precondition is its own
+  check (habit 1), one pack is then raised past the old maximum (habit 7: the
+  **last** pack, which was neither extreme, so the line can only move if the
+  reduction read it), and `peak_soc_floor` is lifted above every cut-out to grade
+  the other side of the conjunction.
+
+* **Part 12g is behaviour now, not source text** (MUTATION.md habit 4). Real
+  `Controller.cycle()`s on a two-pack roster, both packs held at the same SoC and
+  everything else identical, with the packs' own cut-outs as the only thing
+  varied:
+
+      cut-outs A 10 / B 18 % -> decide() got soc_floor=20 %, floor_limited=False
+      cut-outs A 10 / B 35 % -> decide() got soc_floor=35 %, floor_limited=True
+
+  The observable is `PeakDecision.soc_floor` — the argument, echoed back by the
+  shipped `decide()` — so the whole path from `Controller.inverters` to the
+  guard's argument is under test, and the site's **verdict flips** as well as the
+  number. `self.packs[:1]` answers 20 % both times. **Which** option key the floor
+  comes from stays pinned on the source in part 4, because that claim genuinely
+  is about the code's shape; that the option still governs is now graded
+  behaviourally too.
+
+* ⚠️ **A THIRD SURVIVOR, FOUND WHILE FIXING THE FIRST TWO, AND RECORDED RATHER
+  THAN QUIETLY REPAIRED.** The first cut of part 12g varied only **pack B's**
+  cut-out — so `self.packs[-1:]`, grade the site against the **last** pack,
+  agreed with the full roster on both runs and stayed green across all 19 files
+  (+5 bytes). A two-run fixture that only ever moves the second pack pins `[:1]`
+  and not `[-1:]`; it is the same defect one step along, and it was in the fix
+  for this defect. Part 12g now runs the **same pair of cut-outs in both
+  orders**:
+
+      cut-outs A 10 / B 18 % -> soc_floor=20 %, floor_limited=False
+      cut-outs A 10 / B 35 % -> soc_floor=35 %, floor_limited=True
+      ...the SAME PAIR SWAPPED, A 35 / B 18 % -> soc_floor=35 %, floor_limited=True
+
+  `[:1]` answers 20 % on the second run, `[-1:]` answers 20 % on the third, and
+  the roster answers 35 % on both. No single-position slice passes all three.
+  This is the mirror `12h` already ran on the SoC axis, which is where the shape
+  was borrowed from.
+
+* ⚠️ **AND A FOURTH, from the same battery: the EMPTY-roster branch.** Rewriting
+  `binding_soc_floor([])`'s `float(soc_floor)` to `return None` (−43 bytes) was
+  green across all 19 files. It is defensive code — `Controller.inverters` is
+  never empty on a started controller, and `inputs_ok` refuses the cycle before
+  the guard is reached if it were — so nothing in the suite went near it. It is
+  **pinned rather than argued**, in both directions (the option when there is
+  one, `None` when there is not), because a branch with no check is a branch
+  that can be rewritten under a green suite. The check also records why it
+  cannot permit anything either way: `pack_floor_soc` is `None` at an empty
+  roster, and `discharge_permitted()` refuses on a `None` SoC whatever the floor
+  is.
+
+* **`wired_over_limit()` gained a `prepare(ctl)` hook**, inside its retry loop so
+  every attempt grades the same site, which is the only window in which a second
+  inverter can join the roster before the telegrams are fed.
+
+* **In-process mutation rows 22, 22b and 23** record all four survivors, so a
+  later edit that re-degenerates any of these fixtures goes red on a row rather
+  than on nothing.
+
+### 3b. ⚠️ SECOND FIX ROUND — the fix carried the defect it was written to close
+
+Round 2 closed both named survivors, and both of round 3's blockers are the
+**same defect sitting inside that fix**: a check whose TEXT claims more than its
+FIXTURE can observe. Applied to `app/` on `8501e05`, **all 19 files stayed
+green** for both:
+
+| mutation | Δ | the sentence that was too broad | why the fixture could not see it |
+|---|---|---|---|
+| `binding_soc_floor()`: `max(floors)` → `max(floors[-2:])` | **+5 bytes** | *"So the reduction reads **every entry**"* | 12c2's only counterfactual raised the **last** pack (`_deeper[-1]`), and **every window that ends at the roster's end follows the last pack**. On `(30,25,40,35)` both answer 40; on `_deeper` both answer 45. |
+| the `decide()` call site: `self.packs` → `self.packs[:2]` | **+4 bytes** | *"what is reduced is the **ROSTER** and not a POSITION in it"* | all three `_floor_reaching_decide` runs drove a **two-pack** roster, where `self.packs[:2]` **is** `self.packs` — by exactly the argument 12c2 itself makes about two packs being unable to separate max/min/first/last. |
+
+Round 2's *report* stated the narrow, true claim ("no **single-position** slice
+passes all three runs"). The *check in the file* stated the broad one. That gap
+is the whole of round 3.
+
+**THE GENERAL LAW, stated once so the next card can use it:**
+
+> **A fixture of N packs cannot separate two reductions that agree on N packs.**
+> Two cannot separate max from min from first from last. Three cannot separate
+> max from max-of-the-last-two. A single counterfactual that varies one position
+> cannot separate the reduction from any window containing that position.
+
+Its corollary is the reason this section is long: **the regress does not
+terminate in a fixture.** Closing `[:1]` took two packs; `[:2]` took three;
+`[:3]` takes four — and a four-pack run hands `[:4]` the same free pass. Round 3
+therefore does two different things rather than adding one more pack.
+
+**What was added — no shipped behaviour changed, only what observes it:**
+
+* **Part 12c2 gained a ROSTER SET and a computed FAMILY TABLE.** The same four
+  simulated cut-outs with the **deepest moved to each of the four positions**,
+  and fourteen enumerated rewrites of `max(floors)` each checked against every
+  roster. The table is **computed and printed**, and a member with an empty kill
+  list takes the check **red naming it** — so a family member can no longer be
+  added without a fixture that reaches it. `max(floors[-2:])` is killed only by
+  the rosters whose deepest sits at index 0 or 1, which is precisely the data the
+  single last-pack counterfactual could not supply.
+
+* **Part 12c2 gained a LENGTH SWEEP.** `binding_soc_floor()` is a pure function
+  over a list, which is the one place a sweep is cheap: **78 simulated rosters,
+  lengths 1 through 12, the deepest cut-out at every position of each.** That
+  closes *every* head window `max(floors[:w])` and *every* tail window
+  `max(floors[-w:])` of width **1 to 11** in one property rather than one
+  mutation at a time — and the check asserts that width **12 is NOT reached**, so
+  the limit is a red line rather than a silence.
+
+* **Part 12g drives THREE-pack rosters**, with the deep cut-out at index 0, 1
+  **and** 2. Every positional slice of a three-pack roster is a proper subset of
+  `{0,1,2}` and so drops a position; the run whose deep pack sits there answers
+  the option, 20 %, where the roster answers 35 %. `self.packs[:2]` goes red on
+  the index-2 run. `_floor_reaching_decide()` now takes `*floors`, and the extra
+  units join through the same `second_inverter()` hook the two-pack runs use.
+
+* **Part 12g gained a POSITIONAL-SLICE TABLE**, computed against the **real**
+  `Controller.packs` each of the six cycles actually ran and the **real**
+  `PeakDecision.soc_floor` it produced — so it measures the shipped call site's
+  own answer, not a re-derivation, and a survivor takes the check red.
+
+* ⚠️ **AND A FIFTH AND SIXTH SURVIVOR, FOUND BY ROUND 3'S OWN BATTERY AND
+  CLOSED STRUCTURALLY RATHER THAN BY ONE MORE PACK.** `self.packs[:3]` (+4) and
+  `self.packs[-3:]` (+5) survive **all six** behavioural runs, because the
+  longest roster those runs drive is three packs long. Part 12g therefore also
+  pins the roster **argument's identity** on the AST: it must unparse to exactly
+  `self.packs`, which is false of every slice at every length. ⚠️ This is **not**
+  the substring test round 2 removed — `"self.packs" in expr` is *true* of every
+  slice; `ast.unparse(arg) == "self.packs"` is *false* of all of them. The two
+  halves are separated and each says what it reaches: the **runs** grade the
+  VALUE and reach every slice up to N=3; the **pin** grades the ARGUMENT'S
+  IDENTITY at any N and is blind to two things the runs are not — a rewrite of
+  what `Controller.packs` *returns* (the runs' `len(ctl.packs) == 3` catches
+  that) and the reduction *inside* `binding_soc_floor()` (12c2's).
+
+* ⚠️ **AND ONE ROW IS RECORDED AS NOT CAUGHT.** A reduction over a window
+  **twelve packs wide** is indistinguishable from `max(floors)` on every roster
+  in the file, because the sweep stops at twelve. Unlike the call site there is
+  no identity claim to pin — the claim is semantic, "the maximum", and a shape
+  pin would refuse honest refactors of the expression. It is reported **with its
+  size** (it needs a 13-pack roster, on a site whose roster is ONE and whose
+  second unit is ~8 days out) rather than hidden.
+
+* **Two rewrites are EQUIVALENT, not uncaught.** `max(set(floors))` and
+  `list(reversed(self.packs))` cannot change any answer — `max` is order- and
+  duplicate-invariant. The second is nonetheless red on the structural pin.
+
+* **In-process mutation rows 24 – 27** record all four of round 3's findings,
+  including the not-caught one, so a later edit that re-degenerates any of these
+  fixtures goes red on a row rather than on nothing.
+
+## 4. ⚠️ THE HONEST LIMITATION, and it is the reason this record exists
+
+**Under any configuration rule 8 accepts, `binding_soc_floor()` answers
+`peak_soc_floor` for every pack.** Rule 8 refuses `peak_soc_floor <= bms_soc_floor`
+on *every* unit, so `max(peak_soc_floor, bms_i) == peak_soc_floor` everywhere the
+add-on will actually start. The per-pack **floor** is therefore non-degenerate
+only against a config rule 8 refuses.
+
+This is not a defect and it is not hidden. It is the same argument
+`validate.unit_caps_indexed()` makes about itself, in that function's own words:
+
+> *"Rule 9(d) already refuses such a config so the two lists cannot desynchronise
+> in shipped use — but 'unreachable' is a claim about today's rule ordering, not
+> a property of this function, and `validate_startup_config()` is also
+> `sim/inject.py`'s entry point."*
+
+CFG-04's index desynchronisation is what happened the last time that reasoning
+was left implicit. So the reduction is written, and it is graded on both sides:
+`test_peakguard.py` part 12c sweeps **1775** rule-8-valid `(peak_soc_floor,
+bms_soc_floor)` pairs and asserts the answer is the option in every one of them
+(that is AC 5, measured over the whole option space rather than at the shipped
+point), and then asserts that on the pair rule 8 *refuses* the answer is the
+**cut-out** — because without that second line the sweep would be satisfied by
+`soc_floor` typed straight through, and the mutation that deletes the `max()`
+could never bite. It does bite: M2 on the PR.
+
+**What IS live at a rule-8-valid roster** is the rest of the card: rule 8 now
+refuses the two-model config that used to start; the permission is answered per
+pack, so the alarm names the pack that stopped the site rather than "the
+battery"; and an entry with no stated cut-out is withheld instead of defaulted.
+
+## 4b. ⚠️ ROUND 4 — the sibling argument, and SPIKE-04 making this the live axis
+
+Rounds 2 and 3 hardened the **floor** axis: the `max` inside
+`binding_soc_floor()`, the roster handed to it, `Controller.packs`, and
+`pack_floor_pct()`'s conjunction. Round 4's blocker is the same family at the
+**sibling argument of the same call**:
+
+```python
+self.peak_guard = peakguard.decide(
+    ...,
+    soc=self.pack_floor_soc,                      # MINIMUM  <- round 4
+    soc_floor=peakguard.binding_soc_floor(self.packs, ...),   # MAXIMUM  <- rounds 2-3
+```
+
+`peakguard.py`'s own docstring names them as a pair — *"MAXIMUM here pairs with
+the MINIMUM in `pack_floor_soc`"* — and a conjunction is exactly as strong as
+its weaker half. On `52380c0`, with all 19 files green and verified again after
+the rebase onto `3934ad7`:
+
+| mutation in `Controller.pack_floor_soc` | bytes | before round 4 | now |
+|---|---|---|---|
+| `min(float(v) for v in vals[:2])`  | +4 | **GREEN** | RED |
+| `min(float(v) for v in vals[-2:])` | +5 | **GREEN** | RED |
+| `min(float(v) for v in vals[:3])`  | +4 | **GREEN** | RED |
+| `vals[:1]`, `vals[-1:]`, `vals[1:]`, `vals[:-1]`, `max(vals)`, the mean | | RED | RED |
+
+The suite's separating power on the SoC axis stopped at exactly **N = 2** —
+precisely the state the floor axis was in before round 3, and which round 3
+itself named as its blocker 2. A fixture of N packs cannot separate reductions
+that agree on N packs.
+
+**It changes a real answer.** A three-pack roster at 50 / 60 / 11 %, emptiest
+pack **third**: the shipped property answers 11 %, `vals[:2]` answers 50 %. The
+site is then graded for discharge *permission* against a pack 39 points fuller
+than the emptiest, and spends a pack its own BMS stops — through
+`sim/inject.py`, which runs no validator rule at all. The verdict flips with it:
+11 % is below the 20 % EMS floor, so the shipped site is floor-limited and sizes
+no forced discharge, where the mutant is permitted and sizes a positive one.
+
+### ⚠️ SPIKE-04 makes the differing-floor discipline the entire exposure
+
+SPIKE-04 reads pack B as **4 × Dyness DL5.0C, DoD 90 → floor 10 %** — **FROM THE
+DATASHEET AND THE SERIAL. Inverter B does not physically exist (~8 days out) and
+nothing about it has been measured.** Pack A is DoD 90 → 10 % as well, and *that
+one is measured*, off register `0x0560` on the reference GW5000S-BP.
+
+So **production is degenerate on the floor axis**: both packs floor at the same
+value, `max(10, 10) == 10`, and a differing floor exists **only in the
+fixtures**. That is not an argument for simplifying the fixtures to matching
+values — it is the argument for keeping them. `binding_soc_floor()`'s reduction
+is observable *nowhere else*, and the moment a third pack, a replacement pack or
+a different chemistry arrives it is observable in the field. **Anyone who
+"simplifies" `A_PACK_FLOOR != B_PACK_FLOOR_SIM` to one number deletes the only
+data this repository has that can see the reduction at all**; part 12c2's
+precondition check goes red if they do, and this paragraph is why.
+
+The **SoC axis has no such degeneracy**. Two batteries at the same state of
+charge is a coincidence, not a configuration, so `pack_floor_soc` is the half of
+the pair that will be non-degenerate in the field from the day inverter B is
+wired up.
+
+### The treatment, transferred from round 3
+
+* **the roster SET** — six real `Controller.cycle()` runs, the emptiest pack at
+  every position of a three-pack roster and both positions of a two-pack one,
+  the observable read off `PeakDecision.soc` (the argument, echoed) rather than
+  off a spy or a grep. Cut-outs held flat across all of them, so the floor axis
+  cannot be what moved the answers.
+* **the positional-slice table and the non-slice table** — computed against the
+  real `Controller.inverters` each cycle carried and the real decision it
+  produced, printed, with a member that nothing kills taking the check red.
+* **the length sweep** — the real property on real rosters of 1 to 12 inverters,
+  the empty pack at every position. Closes head and tail windows of width 1-11
+  at once. Width 12 and wider is **honestly not reached**, and asserted to be
+  unreached so a later sweep that lengthens the rosters must rewrite the
+  sentence.
+* **the exact structural pin** — three of them, because there are three
+  reductions over roster length in this one property: `vals` is built by one
+  comprehension over the bare `self.inverters`; `any(... for v in vals)` reduces
+  the whole list; `min(... for v in vals)` reduces the whole list. Every slice
+  of either is red at **every** roster length, including the `[:3]` and `[:12]`
+  the runs and the sweep cannot see.
+
+Unlike the floor axis, **there is no uncaught row here**: the claim at
+`pack_floor_soc` is an *identity* ("this list"), so a shape pin is the right
+instrument, where `binding_soc_floor()`'s claim is *semantic* ("the maximum")
+and a shape pin there would refuse honest refactors. That asymmetry is why one
+carries an open row and the other does not.
+
+## 4c. ⚠️ THE ENUMERATION — what OTHER reductions over roster length are graded
+
+This card has now been rejected three times for the same shape one step over, so
+round 4 stopped closing members and enumerated the **family**. Every reduction
+over `self.inverters` / `self.packs` in `Controller` was found from the AST and
+mutated to a slice, one at a time, against the full 19-file suite.
+
+| # | site | reduction | consumer | mutation | result |
+|---|---|---|---|---|---|
+| 1 | `pack_floor_soc` | `min` over SoC | `decide(soc=)`, `arbitrage.decide(soc=)` | `vals[:2]` +4 | **was GREEN → now RED** (12i) |
+| 2 | `pack_floor_soc` | `any(v is None)` | same | `vals[:1]` +4 | RED (raises in 12d; pinned in 12i) |
+| 3 | `pack_floor_soc` | the `vals` comprehension | same | `self.inverters[:2]` +4 | RED (12i sweep + pin) |
+| 4 | `binding_soc_floor` | `max` over floors | `decide(soc_floor=)` | `min`, windows | RED (12c2, round 2-3) |
+| 5 | call site | the roster argument | same | `self.packs[:1..3]` | RED (12g, round 3) |
+| 6 | `Controller.packs` | the comprehension | `binding_soc_floor`, `pack_permissions` | `self.inverters[:2]` +4 | RED (12g three-pack runs) |
+| 7 | `site_batt_w` | `sum` + `any(None)` | `decide(batt_w=)` — sizes the floor | `self.inverters[:1]` +4 | RED (test_inverter.py) |
+| 8 | `site_rating_w` | `sum` of per-unit conjunction | `decide(achievable_w=)`, freeze rail | `[:1]` +4 | RED (test_inverter.py) |
+| 9 | `site_max_w` | `sum` of `max_w` | the site loop's supervised bound | `[:1]` +4 | RED (test_inverter.py) |
+| 10 | `site_dev_bound` | `sum` + `any(None)` | `looks_frozen`, `rail_unreachable` | `[:1]` +4 | RED (test_inverter.py) |
+| 11 | `site_circulating_w` | `circulating_w` over measured power | SAFETY-31 trip | `[:1]` +4 | RED (test_watchdog.py) |
+| 12 | `inputs_ok` | `all` over both readings | gates the whole cycle (§11.1 rule 1) | `[:1]` +4 | RED (test_inverter.py) |
+| 13 | `units` | `tuple` of names | the arbiter's scope table | `[:1]` +4 | RED (5 files) |
+| 14 | `status_payload` | `min(_dues)` over `self.maints` | the operator's "maintenance due" row | `_dues[:1]` +4 | RED (test_maintenance.py) |
+| 15 | `maint_unit` | `self.inverters[self.maint_index]` | which pack the FSM drives | `[0]` −15 | RED (test_maintenance.py) |
+| 16 | store migration | the roster name list | MAINT-05's key migration | `[:1]` +4 | RED (test_maintenance.py) |
+| 17 | `validate_unit_ranges` | the roster argument | startup refusal | `[:1]` +4 | RED (test_inverter.py) |
+| 18 | `cycle()` stale-input hold | `any(sign_wd.tripped)` | **a latched unit's failsafe SET** | `[:1]` +4 | **was GREEN → now RED** (test_watchdog.py part 8) |
+| 19 | `publish()` status | `any(sign_wd.tripped)` | the MQTT status vocabulary | `[:1]` +4 | **was GREEN → now RED** (part 8) |
+| 20 | `status_payload()` banner | `any(sign_wd.tripped)` | the one headline on the page | `[:1]` +4 | **was GREEN → now RED** (part 8) |
+| 21 | `_grade_store_migration` | `any(sign_wd.tripped)` | SAFETY-02's re-arm guard | `[:1]` +4 | was GREEN → now RED (12j), see below |
+| 22 | `cycle()` undeliverable list | `sorted(...)` over shares | the *text* of one event line | `[:1]` +4 | **STILL GREEN — honest gap, below** |
+
+**Rows 18-20 are the finding, and they are not this card's code.** All three are
+`any(i.sign_wd.tripped for i in self.inverters)`, all three are SAFETY-30's, and
+all three survived a green 19-file suite for exactly the reason every blocker on
+this card survived: *the only fixture that reached them was a roster of ONE,
+where `self.inverters[:1]` IS `self.inverters`.* Part 3 of test_watchdog.py has
+built a two-inverter roster with only inverter B latched since SAFETY-30
+shipped — the precise data all three needed — and none of them read it.
+
+Row 18 is the one with teeth. A latched unit must take the whole roster past the
+stale-input hold, because that unit's `failsafe` SET is the thing parking it;
+main.py's own comment says *"the trip would stop acting the moment a poll was
+missed"*. With `[:1]`, a latched inverter B plus a one-cycle gap in inverter A's
+SoC returns early, and B's last share stands for the heartbeat to re-emit.
+test_watchdog.py part 8 now drives that with the latch at **each** position, plus
+the no-latch counterfactual that proves the hold really fires.
+
+**Row 21 — graded structurally, and argued to be redundant.** The `[:1]` there
+is now red on 12j's enumeration, but I could not construct a *reachable* state in
+which it changes an answer: `_grade_store_migration()` runs at startup, before
+any cycle, so a unit is tripped in memory only if its own `unit/<name>/sign_tripped`
+key was truthy — which makes `namespaced_latched` True and short-circuits the
+disjunct. I believe it is an equivalent mutant at that call site rather than a
+live hole, and I am recording the argument instead of asserting the conclusion.
+
+**Row 22 — STILL GREEN, and reported with its size.** `", ".join(sorted(u for u
+in resolution.shares if not self._can_write(u)))[:1]` truncates the **names in
+one event-log line**. It is +4 bytes and no check bites. The refusal itself —
+`elif {u for u in resolution.shares if not self._can_write(u)}` — is a different
+expression and *is* graded (test_peakguard.py part 10h-1b), so the site still
+stops; what a `[:1]` costs is an operator being told one name when two units have
+no writer. It is not a roster comprehension (it iterates `resolution.shares`), so
+12j does not cover it and does not pretend to. Closing it needs a three-inverter
+fixture with two writer-less entries, which is ALLOC-01's fixture and not this
+card's. **Filed as open, with its size and its consequence, rather than closed
+quietly or left unmentioned.**
+
+### And the family closed rather than the member
+
+`test_peakguard.py` part 12j enumerates the family from the AST and requires
+every member to take the roster **whole**, so a new reduction over a slice is red
+**on the line it is written**, at every roster length, with no fixture required.
+That check is what would have caught rounds 2, 3 and 4's blockers on the round
+they were written instead of one review round each; it is also what found rows
+18-21.
+
+⚠️ **AND IT WAS STILL TOO NARROW — see §4d.** Round 4's version enumerated the
+26 roster comprehensions inside the `Controller` class, because that is where
+the four known sites were. Round 5's blockers were four reductions in
+`validate.py`, one module over, over a list *derived* from the roster three
+calls away from it. The pin now parses every `.py` under `app/` and finds the
+roster by transitive closure from one option key: **183 reductions across 9
+modules.**
+
+## 4d. ⚠️ ROUND 5 — the same family one MODULE over, and an instrument that discovers its own scope
+
+Round 4 enumerated the family and closed it **inside the `Controller` class**,
+because that is where the four known sites lived. The review found four more
+survivors immediately, in `validate.py`, on a 19/19 green suite:
+
+| site | mutation | delta | suite |
+|---|---|---|---|
+| `validate.py:779` | `min(caps)` → `min(caps[:1])` | +4 B | **GREEN** |
+| `validate.py:779` | `min(caps)` → `min(caps[-1:])` | +5 B | **GREEN** |
+| `validate.py:778` | `caps = [cap for _, cap in caps_ix[:1]]` | +4 B | **GREEN** |
+| `validate.py:893` | `min(caps_ix[-1:], key=lambda p: p[1])` | +5 B | **GREEN** |
+
+**None of them is an equivalent mutant — a safety refusal disappears.** With
+`max_w: 5000` on inverter-a beside `2000` on inverter-b and
+`sign_disagree_w: 3000`, the shipped validator answers one problem —
+*"sign_disagree_w is 3000 W but max_w (inverter-b) is 2000 W, so the SAFETY-02
+sign-disagreement watchdog can never fire"* — and every one of the four answers
+**zero**. The site starts, with a watchdog reporting `armed` on the status page
+that cannot trip on pack B. That is rule 5's own failure mode reached **through**
+rule 5, which is the sentence `test_inverter.py:1657` says the rule exists to
+prevent. Rule 6 loses its refusal the same way.
+
+### Why round 4's pin could not see them, and why the fix is not four more checks
+
+`caps` and `caps_ix` are not comprehensions over `self.inverters`; they are lists
+**derived** from the roster, three function calls away from it, in a module the
+enumeration never opened. Closing them by hand would have produced a fifth
+rejection with the same shape one step over — that is the whole record of this
+card. **A hand-written scope is the same defect as a hand-written fixture**
+(MUTATION.md habit 12): a check whose data cannot reach the failure it names.
+
+### The instrument
+
+`test_peakguard.py` part 12j now parses **every `.py` under `app/`** off disk —
+no module is named anywhere in the check — and finds the roster by transitive
+closure from **one seed**, the `inverters` option key:
+
+* a function whose returns are roster-carrying is **roster-producing**
+  (`roster_entries` → `build_roster` → `unit_caps_indexed` → `unit_caps`);
+* a name assigned one carries it, **and so does a list accumulated in a loop
+  over one** — which is exactly what `caps`, `roster` and `problems` are, and
+  what round 4's rule could not express;
+* an attribute or property answering one carries it (`self.inverters`,
+  `Controller.packs`, `Controller.units`, `live_units()`);
+* **an argument at a call site taints that parameter in the callee**, which is
+  how the pin walks into `peakguard.binding_soc_floor`, `arbiter.resolve`,
+  `allocator.plan`, `circulation.circulating_w`, `maintenance.arbitrate` and
+  `store.migrate_maint_keys` without being told they exist;
+* and **a slice of a roster is still a roster**, so a mutation cannot cut the
+  taint and hide every reduction downstream of itself. An **index** is one unit
+  and is not.
+
+It then requires, at every place a roster-carrying value is reduced or iterated,
+that the whole of it arrives: no `[:1]`, `[-1:]`, `[:2]` or `[0]` between the
+roster and the reduction.
+
+### What it found — and the hand-written list was wrong in BOTH directions
+
+**183 reductions across 9 modules**, out of 23 `.py` files parsed:
+`main.py` 96, `allocator.py` 24, `validate.py` 19, `arbiter.py` 14,
+`circulation.py` 10, `maintenance.py` 10, `peakguard.py` 4, `inverter.py` 3,
+`store.py` 3 — and 14 modules with no roster reduction at all.
+
+The card's own suggested module list named `watchdog.py`, which reduces over no
+roster at all (SAFETY-30's sign watchdogs are strictly per-unit — there is
+nothing to slice), and did **not** name `maintenance.py` or `store.py`, which
+both do. A pin built from that list would have made a vacuous claim about one
+module and no claim at all about two others. That is the argument for computing
+the scope, made with data rather than with an assertion.
+
+The pin **independently rediscovers all four blockers** — it is told one option
+key and nothing else — and finds a **fifth** beside them at
+`validate.py:783`, the `min(caps_ix, key=...)` inside rule 5's message, which no
+review round named.
+
+### The counterfactual, at two depths
+
+* **Per site, all of them.** Every enumerated site's own expression, in its own
+  scope, mutated with each of the four cuts this card has actually been defeated
+  by. **183 sites × 4 cuts = 732** mutated spellings; every one reported. The same run asserts
+  the predicate **accepts** the legitimate wrapped forms the package really uses
+  (`enumerate`, `zip`, `sorted`, `pack_permissions(packs, floor)`) and does not
+  treat a keyed lookup (`weights[u]` in `allocator._fill`) as a slice — which is
+  what four false SLICED reports cost before `shortens()` was written.
+* **End to end, on the real files.** `[:1]` written into `app/validate.py` at
+  each blocker position, the **whole** analysis re-run over the mutated source,
+  and a sliced site required at that exact line — where the clean package
+  reports none. This is the check that would have taken PR #48 red four rounds
+  ago, with no fixture reaching it.
+
+### The sweep, and the number that must not be quoted alone
+
+All 183 sites were mutated to `[:1]`, one at a time, +4 bytes each, and each
+mutant run against the full 19-file suite in `goodwe-addon-ci` (mounted `:ro`,
+`python3 -B`, a fresh rsync per mutant; 0 `.pyc` in the tree before and after —
+a read-only mount cannot write one, so TEST-15 is closed by construction here
+rather than by discipline). **183 of 183 RED.**
+
+⚠️ **On its own that is tautological**: with the pin in the tree every slice is
+red *by the pin*. So all 51 mutants whose first red was `test_peakguard.py` were
+re-run with the pin **neutralised** (`_SLICED` blanked), leaving only the
+behavioural checks:
+
+| | |
+|---|---|
+| **145 of 183** | a behavioural fixture in this repository separates the site from a slice of itself — red with the pin turned off |
+| **38 of 183** | **nothing but this pin sees it.** Structurally closed by this card; behaviourally **UNGRADED**, and listed rather than counted as covered |
+
+The 38: `main.py` 27, `allocator.py` 6, `validate.py` 2, `arbiter.py` 1,
+`circulation.py` 1, `maintenance.py` 1. Grouped by what a `[:1]` there costs:
+
+* **The operator's page — 15, the largest group.** `Controller.checks`
+  (3310, 3311, 3319, 3328, 3330, 3347, 3368, 3370, 3400, 3458) and
+  `status_payload` (3556, 3566, 3578). A slice reports one unit's row where two
+  exist, or "1 of 2 live" reading 1 of 1. Nothing commands differently; what is
+  lost is the evidence a human uses to notice that it should.
+* **The write path's own counts.** `write_setpoint` 1267/1272/1280 — three
+  `len(targets)` guards. The write itself iterates `targets` at 1287 and *is*
+  graded (test_inverter.py); these three are its log arithmetic and refusal
+  count.
+* **The allocator's internals.** `_fill`'s zero-weight last-resort pool (365),
+  `plan`'s `dropped` (526, 653), `free` (584), `frac_order` (591). ALLOC-01
+  drives two and three units through the *weighted* pass; the last-resort pass
+  and the largest-remainder tie-break are reached, but not with enough units for
+  a slice to change the answer.
+* **Startup and FSM plumbing.** `__init__` 235/351, `_only` 831,
+  `_maint_button` 805, `cycle`'s maintenance zip 1505, `send_heartbeats` 3015,
+  `check_output_clamp` 2445/2452, `check_circulating` 2701,
+  `maintenance.arbitrate` 547, `arbiter.site_resolve` 517,
+  `circulation.opposing` 242.
+* **Two refusal-TEXT sites.** `validate._roster_problems`'s `len(entries)` (554)
+  and `refuse()`'s numbering loop (1263) — both shape the words of a refusal
+  that still happens.
+* **`_grade_store_migration` (698)**, already row 21 of §4c, argued there to be
+  an equivalent mutant at that call site. The argument is unchanged and is still
+  an argument, not a proof.
+
+⚠️ **None of the 38 is closed behaviourally by this card, and saying so is the
+point.** Closing sites one at a time is what cost this card four review rounds.
+The pin closes the **family** — a slice at any of them is red on the line it is
+written — and this list is what a shape pin can never promise.
+
+### And the behavioural half, because a shape pin cannot grade a meaning
+
+The pin grades an **identity** ("the whole roster arrives"). `min` → `max` is a
+zero-byte edit and invisible to it, forever. So `test_validate.py` grows a
+**roster SET** for the three rules that reduce over `unit_caps_indexed()`:
+rosters of width 2, 3, 4 and 5 with the one small cap at **every position** —
+14 rosters × 3 rules = 42 runs of the real validator — plus a **computed family
+table** of twelve candidate reductions (`max`, `first`, `last`, the mean, and
+`[:1]`, `[-1:]`, `[:2]`, `[:3]`, `[1:]`, `[:-1]`, `[::2]`) each compared against
+what the shipped validator actually said on the same roster. Only `min` agrees
+everywhere; any member no roster kills is **printed as a named survivor** and
+takes the check red.
+
+### ⚠️ A THIRD RULE WAS READING THE FLAT `max_w`, AND IT IS SAFETY-30's
+
+Found by reading the three branches side by side — **not** by the pin, and said
+that way because it is the shape of what the pin cannot see. Rule 5's sibling
+branch, `unit_sign_disagree_w` (SAFETY-30's per-inverter sign watchdog), was
+graded against `_number(opts, "max_w", 2000.0)` — the **flat** option — three
+lines under a branch that had already stopped doing that. Both directions were
+measured before the fix:
+
+* a roster of two 2000 W units beside a leftover `max_w: 5000` from a
+  single-inverter install, with `unit_sign_disagree_w: 3000`, produced **zero
+  problems**. The site started, the status page said `armed`, and the per-unit
+  watchdog could not trip on **either** unit. Identical sentence to the blocker,
+  reached through the branch beside it;
+* and a roster of two 5000 W units with no flat key was **refused** at 3000 W
+  against a 2000 W *default the operator never wrote*, for a threshold both
+  units can reach.
+
+It takes the same `weakest` the branch above takes, from the same list, and
+names the same unit. At a roster of one `unit_caps()` is `[max_w]`, so the
+shipped single-inverter refusal is the same comparison, the same boundary and
+the same sentence. Both directions are asserted in `test_validate.py`.
+
+### ⚠️ WHAT THE PIN CANNOT SEE — open rows, with sizes
+
+1. **Semantics.** `min` vs `max` vs the mean: zero-byte edits, invisible to any
+   shape pin. Only the behavioural sets above can see them, and they only see
+   the rules they drive.
+2. **Direct index sites that are not reductions.** `self.inverters[0]` in
+   `_only()` and `actuator_of()`, `self.inverters[self.maint_index]` in
+   `maint_unit`, `entries[index]` in `_unit_label()`. Single-unit lookups, meant
+   to be, graded where they live.
+3. **A subscript by a NAME.** `weights[u]`, `cap[u]`, `add[u]` in
+   `allocator._fill` are keyed lookups into a roster-derived mapping and are
+   accepted deliberately, so `caps[i]` with a variable `i` would pass. Not in
+   the family this card has been defeated by; buying it costs four false reports.
+4. **A slice through an intermediate call.** `sorted(roster)[:1]` subscripts a
+   call result, not a roster reference. Nothing in `app/` is written that way
+   today; if something is, it would not be seen.
+5. **Anything outside `app/`.** `tools/`, `sim/` and the checks themselves are
+   not parsed — and `sim/inject.py` reaches `validate_startup_config()`.
+6. **The taint's own seam.** It crosses a call boundary only where the callee is
+   a plain function this package defines and the argument is positional or
+   keyword. A roster handed through `*args`, stored in a dict and read back, or
+   passed to a method on an unresolvable object, is lost at that hop — and
+   everything downstream goes **unenumerated** rather than reported unreachable.
+   That is the shape of the remaining exposure: not zero, and not measurable
+   from inside the check.
+7. **`cycle()`'s undeliverable-unit log line** (row 22 of §4c) is still green at
+   +4 bytes, unchanged from round 4 and still filed open.
+
+## 5. ⚠️ THE RESIDUAL — a per-pack EMS floor is NOT this card
+
+`peak_soc_floor` is still **one number for the site**, so the card's own
+"or the deeper pack is needlessly withheld" half is not closed and this record
+does not pretend it is. With cut-outs of 10 % and 18 %, rule 8 obliges the
+operator to set the EMS floor above 18, and the 10 % pack is then held above its
+own need. Closing that means `peak_soc_floor` becoming a per-entry key too, which
+is a second option migration and a product decision about what the site-wide
+number then means. The card scoped itself to `bms_soc_floor` and explicitly told
+this developer not to widen it, so it is filed here as the open question it is
+rather than smuggled in.
+
+**Also still not in this card, and named by the shipped code already:** the
+charge *ceiling* is the mirror image — `pack_floor_soc` is the wrong reduction
+for it, because a ceiling is the **fullest** pack and `arbitrage`'s `soc_ceiling`
+takes one number. `main.py:932-936` says so, and it belongs to CFG-04/SPIKE-04's
+per-pack bound. Nothing here touched it.
+
+## 6. What was changed, and one thing that was found on the way
+
+* `config.yaml` — `bms_soc_floor: int(0,50)` required per `inverters:` entry;
+  the flat key and its default are untouched and are documented as the
+  single-inverter shape's own cut-out.
+* `app/inverter.py` — `Inverter.bms_soc_floor`; `_entry_bms_floor()` (`None`, not
+  a borrowed number and not `0.0`); `_flat_bms_floor()`.
+* `app/peakguard.py` — `Pack`, `pack_floor_pct()`, `pack_permissions()`,
+  `binding_soc_floor()`. `discharge_permitted()` is unchanged and is still the
+  one place the question is answered.
+* `app/validate.py` — `unit_bms_floors_indexed()`; rule 8 grades every unit and
+  names it via the **roster** index the value came off.
+* `app/main.py` — `Controller.packs`; the `decide(soc_floor=…)` reduction; the
+  floor-limited notification names the pack(s) at or below their own floor, at a
+  roster of two or more only.
+* `tools/supervisor_shape_probe.py` — **re-run, and repaired.** MUTATION.md
+  habit 8: a committed transcript is a check and it decays. Making the key
+  required broke §C outright and, worse, left §D printing **PASS** on a refusal
+  about the *wrong key* — its "no `max_w`" case was answered `Missing option
+  'bms_soc_floor'`. §D is now an isolated counterfactual over a **merged,
+  accepted** baseline with exactly one key varied per case, asserting the key's
+  **name** in the refusal, and it carries a `bms_soc_floor` case in both
+  directions. Re-run against `ghcr.io/home-assistant/amd64-hassio-supervisor:2026.08.0`:
+  `all cases passed`.
+* `app/inverter.py`, found by the mutation battery — `_flat_bms_floor()` was
+  written with the default in **two** places (the `.get()` fallback *and* the
+  blank test). Deleting either one survived, because each covered for the other:
+  MUTATION.md's masking section in three lines of option reading. It has one
+  defaulting line now, and M12 takes six checks red.
+
+* **Round 3 changed no `app/` file at all.** `test_peakguard.py` only:
+  parts 12c2 and 12g. Its battery was **46 mutations across
+  `binding_soc_floor()`'s reduction, the `decide()` call site, `Controller.packs`
+  and `pack_floor_pct()`'s conjunction** — bytecode purged and counted before and
+  after each (23 → 0). **43 red, 3 survivors, all three recorded above and in the
+  in-process rows**: `max(floors[:12])` and `max(floors[-12:])`, which need a
+  13-pack roster to observe and are reported with that size rather than hidden;
+  and `max(set(floors))`, which is **equivalent** — `max` is duplicate-invariant,
+  so it cannot change an answer. `list(reversed(self.packs))` is equivalent too
+  (`max` is order-invariant) and is nonetheless red on the structural pin.
+
+⚠️ **No measurement of inverter B appears anywhere in this change.** It does not
+physically exist. Every second-pack number in a fixture, in the probe and in
+config.yaml's commented example is **simulated and labelled as such**; only the
+10 % on inverter A is read off hardware. The three-pack runs added in round 3 are simulated
+twice over: there is no inverter C at all, and the shallow slots carry inverter
+A's measured 10 % while the 35 % cut-out that moves along the roster is invented.
+
+---
+
+## 7. The probe transcript, re-run 2026-09-05 on 2026.08.0
+
+Command (unchanged, in `tools/supervisor_shape_probe.py`'s own docstring):
+
+```
+    docker run --rm -v "$PWD:/w:ro" -v "$PWD/tools:/probe:ro" \
+      --entrypoint python3 \
+      ghcr.io/home-assistant/amd64-hassio-supervisor:2026.08.0 \
+      /probe/supervisor_shape_probe.py
+```
+
+It reads `config.yaml` and runs Supervisor's own `AppOptions` validator in a
+throwaway container. It touches no live Supervisor, POSTs nothing and installs
+nothing.
+
+⚠️ **RE-RUN AGAIN ON 2026-09-05**, because the rebase onto `67e649a` merged
+SPIKE-04a's `max_w: 4600` into the same §C/§D blocks this card had rewritten,
+and MUTATION.md habit 8 says a committed transcript that a document quotes is a
+check. A hand-merged transcript is not a measurement of anything. The block
+below is the output of that run, not of the 2026-09-04 one: B's rating reads
+**4600** — its datasheet figure, still not a measurement of any unit — and every
+case still passes.
+
+```
+== C. AC2: a two-inverter blob an operator would POST ==
+  PASS  two inverters
+        [{"name": "inverter-a", "setpoint_entity": "number.goodwe_a_setpoint_w", "soc_entity": "sensor.goodwe_a_soc", "batt_entity": "sensor.goodwe_a_battery_power", "max_w": 5000, "bms_soc_floor": 10}, {"name": "inverter-b", "setpoint_entity": "number.goodwe_b_setpoint_w", "soc_entity": "sensor.goodwe_b_so
+
+== D. what the schema itself refuses, per entry ==
+  PASS  the per-entry BASELINE is ACCEPTED, so every refusal below has nowhere else to come from
+        [{"name": "inverter-b", "setpoint_entity": "number.b", "max_w": 4600, "bms_soc_floor": 10}]
+  PASS  an entry with no name is refused, and the refusal NAMES it
+        Missing option 'name' in inverters in GoodWe RS485 Controller (local_goodwe_controller)
+  PASS  an entry with no setpoint_entity is refused, and the refusal NAMES it
+        Missing option 'setpoint_entity' in inverters in GoodWe RS485 Controller (local_goodwe_controller)
+  PASS  an entry with no max_w is refused, and the refusal NAMES it
+        Missing option 'max_w' in inverters in GoodWe RS485 Controller (local_goodwe_controller)
+  PASS  an entry with no bms_soc_floor (SAFETY-32) is refused, and the refusal NAMES it
+        Missing option 'bms_soc_floor' in inverters in GoodWe RS485 Controller (local_goodwe_controller)
+  PASS  an entry with max_w over the range is refused, and the refusal NAMES it
+        value must be at most 5000.0
+  PASS  an entry with bms_soc_floor over the range (SAFETY-32) is refused, and the refusal NAMES it
+        value must be at most 50.0
+  PASS  a JSON STRING where the list belongs is refused
+        Invalid list for option 'inverters' in GoodWe RS485 Controller (local_goodwe_controller)
+
+== E. the ROLLBACK direction, and the operator's UI ==
+  PASS  a schema WITHOUT `inverters` drops the key with a warning rather than refusing - so a downgrade is not the §B trap in reverse
+        ['arbitrage_enabled', 'arbitrage_soc_ceiling', 'arbitrage_soc_floor', 'auto_start', 'batt_entity', 'batt_invert']
+  PASS  Supervisor's UI renderer turns it into a repeatable section rather than choking - an operator can add the second inverter in the Configuration tab, which the JSON-string alternative could not offer
+        [{"name": "inverters", "type": "schema", "optional": true, "multiple": true, "schema": [{"name": "name", "required": true, "type": "string"}, {"name": "setpoint_entity", "required": true, "type": "string"}, {"name": "max_w", "lengthMin": 100.0, "lengthMax": 5000.0, "required": true, "type": "integer
+
+== all cases passed ==
+```

goodwe_controller/DECISIONS/SAFETY-37-freshness-policy.md

@@ -0,0 +1,376 @@
+# SAFETY-37 — the freshness policy, and the one sentence in the card that had to be rewritten
+
+**Status: DECIDED 2026-09-06.** A per-unit reading that has stopped following its
+own command is reported to its consumers as **`None`**, never as a held number.
+The verdict is a **conjunction**, not an age threshold, and this document records
+why an age threshold is not available at this layer — which is the one place the
+card's wording could not be implemented as written.
+
+Filed with SAFETY-37. Card `6a9a7eda7932387c3acbd700`, scope widened by the
+architect pass of 2026-09-06 to carry the single policy for [[TEL-06]] and
+[[TEL-08]] as well.
+
+Every figure below was measured or read out of this repository on **2026-09-06**
+and is re-derived by `test_freshness.py` on every run. Where a number is carried
+forward from an earlier measurement, the section and the date it was taken are
+given at the number.
+
+---
+
+## 0. The three faces, and which one this card built
+
+| where | the defect | this card |
+|---|---|---|
+| **Layer 1** — `goodwe/master/goodwe-master-stage4-failsafe.yaml:690` | the ingest-age veto tests the **VALUE** of `sensor.goodwe_p1_sample_age`, not its arrival. A dead publisher freezes it at a healthy number and the veto can never fire | **not touched.** It is firmware, behind a flash. §5 says what it owes |
+| **The add-on** — `app/hass.py:69-82` | returns a held value as a value. Nothing separates "read 40 %" from "still says 40 % because nothing updated it" | **built here** |
+| **The evidence** — [[HW-01]] | SoC held 40 % for 6 h 25 m while the pack drained to its floor, every detector reading healthy | the case the policy is answerable to |
+
+The two consumers the card names — SAFETY-30's per-unit sign check and
+SAFETY-31's circulating-power sensor — both read `Inverter.batt` (register
+`0x0518`) and **neither had a freshness gate of any kind**. Both already do the
+right thing with a `None`: `watchdog.SignWatchdog.evaluate` **clears** its window
+on a `None` measurement, and `circulation.circulating_w` returns `None` for a
+roster with a missing term, which clears that window too. **Neither could ever
+receive one.** The gate is the piece that was missing *between* the shipped read
+and the shipped checks, which is why the change to each consumer is zero lines.
+
+---
+
+## 1. ⚠️ The sentence that had to be rewritten, and why saying so is the finding
+
+The card says: *"A pack legitimately resting at 40 % and a dead sensor reading
+40 % are the same number; **only arrival separates them**."*
+
+**For a signal this add-on polls out of Home Assistant's state cache, arrival
+does not separate them, and cannot.** `read_inputs()` runs about once a second
+(`run_control()`'s `await asyncio.sleep(1)` bounds the loop body), and while the
+entity exists Home Assistant answers `200` with a number **whether or not the
+publisher behind it is alive**. So both members of the pair arrive, identically,
+for ever. `test_freshness.py` part 1a builds an arrival-age gate and grades it:
+the age since arrival is `0.0 s` at every instant of **both** runs. A threshold
+on it is a threshold that can never fire — which is TEL-06's own defect rebuilt
+one layer up.
+
+The other half of the card's rule survives intact and is honoured absolutely:
+
+> ⚠️ Home Assistant's `last_updated` does **not** move when a value is rewritten
+> unchanged, so it cannot be the source of truth.
+
+Neither does `last_changed`, and this project measured on the ENV-01 rig (70 s of
+a frozen meter) and independently against the live house that `last_reported`
+does not advance on a repeat on either serialiser either —
+`p1.HomeWizardLocalSource`'s docstring records both. **`app/freshness.py` reads
+no Home Assistant timestamp at all.** Every clock in the verdict is
+`time.monotonic()` inside this process, stamped at the instant an arrival carried
+a different number. That is what "arrival-stamped" can mean here, and it is
+graded (part 1a asserts the module's body contains no `last_updated`).
+
+**So the criterion was rewritten rather than approximated:** *a reading is stale
+when it has not moved through a change it was obliged to follow.* The obligation,
+not the age, is what separates the pair.
+
+---
+
+## 2. The verdict
+
+```
+STALE  ⟺  unchanged for ≥ 35.0 s
+          AND |standing command now| ≥ 250 W
+          AND |standing command now − standing command when the reading
+               last changed| ≥ 250 W
+```
+
+Latched: **only an arrival carrying a different number clears it.**
+
+`0x0518` is the inverter reporting **itself** — r = 0.998 with battery power
+against r = 0.09 with the real meter (`goodwe/NOTES.md` §3.3) — and it tracks its
+own command: command and actual agreeing within 4 W once settled (§5.10,
+measured 2026-08-22), the register dithering ±1 W while holding (§5.11, same
+day). A unit told to move 250 W and still answering the same integer watt is not
+tracking.
+
+### 2.1 Why a bare "unchanged for N seconds" threshold is not available
+
+**Measured, not feared.** Replaying the committed 30-day capture of this house's
+own 1 W-resolution power entity — `scenarios/p1-net-30d-2026-08/`, 485,841
+samples straight out of Home Assistant's recorder, where a row exists only when
+the state string **changed**, so the gap between two rows *is* the unchanged
+duration every consumer saw:
+
+| | |
+|---|---|
+| longest unchanged run over 30 days | **263.2 s** (held −899.0 W, 2026-08-11 17:04) |
+| runs ≥ 35 s | 10 of 485,840 (0.0021 %) |
+| runs ≥ 17 s | 386 of 485,840 (0.0794 %) |
+
+A real power figure at 1 W resolution held **one value for four and a half
+minutes with nothing whatever wrong**. So an unchanged threshold free of false
+positives must be over 263 s — and 263 s is **3.5× too slow** to protect a
+consumer that trips at 75 s. There is no admissible threshold. The conjunction
+is not a refinement; without it the card has no implementable verdict.
+
+⚠️ **That is the METER's register, not `0x0518`, and it is used as a surrogate
+and named as one.** No 30-day capture of the inverter's own power exists — it is
+not in the recorder export. The single thing this measurement is used for is the
+statement above: that the legitimate unchanged duration of a power entity in this
+house is *minutes*. It is not used to set the bound.
+
+⚠️ **And every one of those long runs happened under an unmoving load** — the
+worst is 263 s of a steady −899 W export, a house doing one thing. That is why
+the conjunction keys on command travel: none of them arms it.
+
+### 2.2 Why the magnitude term exists — a surviving mutation put it there
+
+Deleting `abs(standing_w) < move_w` from `_grade()` left **every check in the
+first draft green**, because in all of them a command that had *travelled*
+250 W had also *ended up* above 250 W. The case that separates them is a site
+being brought to **rest**: the write path is serialised, so a register can reach
+its new value on the same read at which the *old* command is still standing —
+`standing_at_change` then captures 1300 W, the site is commanded to 0 W, and the
+travel term alone reads 1300 W of unfollowed command for as long as the site
+rests. It would call a perfectly truthful +5 W reading dead. The magnitude term
+is what says *a site at rest is not owed movement*, and part 4 now grades it.
+
+**The hole that term leaves cannot mislead either consumer**, which is why it is
+the right trade: a unit commanded under 250 W is one `watchdog.disagrees()` is
+`False` for whatever the measurement says, and a frozen term beside a live unit
+that is itself resting nets to **zero** circulating power rather than to a false
+alarm. Both halves are asserted, not argued.
+
+---
+
+## 3. The bounds — one per signal, each with its derivation
+
+⚠️ **One constant for both signals would be useless on SoC or trigger-happy on
+power**, which is the third clause of the policy. `freshness.BOUNDS` carries them
+as data with a `wired` column, and `test_freshness.py` part 7 walks the AST of
+every shipped module to check that column tells the truth.
+
+### 3.1 `batt` — `0x0518`, S16, 1 W, published every 10 s — **WIRED**
+
+**Floor, 17.0 s** — the fastest a healthy register can be *obliged* to have
+answered. Three terms, each read out of this repository:
+
+| | | source |
+|---|---|---|
+| 6.0 s | the plant | `goodwe/NOTES.md` §5.9, measured 2026-08-22 with the poll temporarily at 1 s: 26 W at +1.43 s, 469 W (94 %) at +3.34 s, settled 507 W at +6.05 s |
+| 10.0 s | the publisher | `firmware/goodwe-master.yaml:181`, `update_interval: 10s` on the `modbus_controller` carrying both `0x0518` and `0x050E` |
+| 1.0 s | this add-on's read period | `main.run_control()`'s `await asyncio.sleep(1)` |
+
+**Ceiling, 75.0 s** — the tighter of the two consumers, both read out of the
+shipped `config.yaml`: `circulation_hold_s` **75** (line 512) and
+`unit_sign_disagree_s` **85** (line 451). A gate slower than its consumer hands
+over the frozen number and explains afterwards.
+
+**Chosen: 35.0 s.** The admissible band `[2 × 17.0, 0.5 × 75.0] = [34.0, 37.5]`
+contains four integers, and **the band is what is derived — 35 is a choice inside
+it**, deliberately not 30 (that is `validate.FIRMWARE_INGEST_VETO_S`, and would
+read as a borrowed constant nobody re-derived) and not 60 (round). Part 6
+computes both ends **from `config.yaml`** and goes red if an operator default
+moves: drop `circulation_hold_s` to 60 and this fails.
+
+**`MOVE_W` = 250 W** is the **largest** admissible value, not a sensitivity
+preference. The gate must arm everywhere a stale reading could mislead a
+consumer; the earliest either consumer speaks is `unit_sign_disagree_w`, 250 W
+(config.yaml:450), because below that `watchdog.disagrees()` is `False` whatever
+the measurement says. Taking the ceiling of the admissible range minimises
+spurious arming. It is pinned to `config.yaml` by part 6, not to a literal.
+
+### 3.2 `soc` — `0x050E`, U16, 1 %, published every 10 s — **STATED, NOT WIRED**
+
+SoC **cannot use the conjunction above.** A pack resting at its floor holds one
+percent for hours with nothing wrong — the card's own example — and the standing
+command says nothing about it, because 0 W is exactly what a rested pack is
+given. The obliged movement for SoC is **energy, not command travel**: one
+percent of pack A is ≈ **153.6 Wh** (15.36 kWh nominal, `goodwe/NOTES.md` §1.1b's
+table — ⚠️ **NOMINAL and FROM DATASHEET**, not a measured usable capacity), so at
+pack A's 5000 W ceiling one percent takes at least **110 s**, and at a realistic
+1000 W about **553 s**.
+
+So the bound is *"SoC unchanged while ∫|battery power| dt since its last change
+exceeded K × 153.6 Wh"*, and **K cannot be chosen from anything written down
+today**. Wiring it with a guessed K would be a gate that fires on a rested pack,
+which is the hazard, not the fix. `Freshness` takes its obligation term from the
+caller precisely so an energy integral can be handed in where command travel is
+handed in for `batt` — TEL-08 needs no second mechanism.
+
+---
+
+## 4. What changes on a running install
+
+| | before | after |
+|---|---|---|
+| healthy register, N=1 | value reaches consumers | **identical** — 60 reads of a dithering register under a reversing command, asserted in part 5 |
+| healthy register, N≥2 | value reaches consumers | identical |
+| **frozen register, N=1** | reads as a healthy measurement, for ever | **site stops**: `inputs_ok` False → `stale_input_s` hold → 0 W, and keeps commanding |
+| **frozen register, N≥2** | per-unit sign check false-trips at 85 s and parks a healthy inverter; circulation sensor reports a loop that is not happening | both consumers get `None`, both windows **clear** |
+
+⚠️ **The N=1 row is a behaviour change on the roster that is running in a house
+today, and it is named rather than hidden.** It is also the point of the card:
+HW-01 was a one-inverter site. The direction it fails in is the safe one — a
+false verdict commands 0 W and keeps commanding (§11.1 rule 1), behind the
+existing `stale_input_s` hold, and clears itself on the register's next move.
+
+The counterfactual is run, not argued. `test_freshness.py` part 3 drives real
+`cycle()` calls at N=2 with A's register frozen at −1200 W and B's live at
++900 W, the command travel produced by the shipped `compute()` and allocator:
+
+```
+standing on A: [0, 445, 890, 1335, 1335, ...]      (the shipped control law)
+gated       : sign trip tick=None   circulating_w=[1800, 1800, 1800, None, None, ...]
+counterfact : sign trip tick=11      circulating_w=[1800, 1800, 1800, 1800, 1800, ...]
+```
+
+---
+
+## 5. What TEL-06 and TEL-08 still owe
+
+**[[TEL-06]] — layer 1, Blocked, and nothing in this card can reach it.** The
+ESPHome veto tests the *value* of `sensor.goodwe_p1_sample_age`. This policy
+lives in the add-on, on the other side of a flash, and cannot help. What TEL-06
+owes is the same mechanism **inside the firmware**: a `millis()` stamp taken when
+the setpoint/age entity is *written*, and a veto on `millis() − last_write_ms`
+rather than on the published number. It is narrowed to that one substitution —
+the policy question ("arrival, not value") is answered here; the remaining work
+is a firmware stamp and a flash, which is a supervised human step.
+
+**[[TEL-08]] — stale SoC.** It owes exactly three things, and no mechanism:
+1. a **measured** usable capacity for pack A (or a defensible bound on it) — the
+   153.6 Wh per percent above is nominal and from the datasheet;
+2. the **energy integral** since the reading last changed;
+3. the constant **K** — how many percent-equivalents of throughput must pass
+   before an unmoved SoC is a fault.
+
+It should consume `freshness.Freshness` with `BOUNDS["soc"]` filled in, not
+restate the policy. The row is already in the table with `wired=False` and the
+reason, and part 7 goes red the day that column stops being true.
+
+**⚠️ Neither of them, and not this card, closes HW-01's whole class.** See §6.
+
+---
+
+## 6. Known survivors, with their size
+
+Graded in `test_freshness.py` part 9, so they are residuals rather than
+surprises.
+
+| # | kind | what survives | size |
+|---|---|---|---|
+| 1 | **false positive** | an inverter physically unable to follow — saturating, thermally derating, or a BMS refusing a charge — is declared stale while telling the truth | one spurious **site stop**, behind `stale_input_s`, self-clearing the moment the register moves. It cannot drive the battery anywhere |
+| 2 | **miss** | a register frozen under a command that never travels 250 W is never detected, for 400 s or for ever | ⚠️ scoped for ONE consumer, NOT both, and the earlier claim here was wrong. TRUE for the per-unit sign check: no such check can speak about that unit (`unit_sign_disagree_w` = 250 W). **FALSE for circulation.** "Contributing at most 250 W" bounds the COMMAND; once the register is frozen its REPORTED value is unrelated to the command, which is exactly HW-01's shape - commanded ~0 W, register stuck on the last large number. Measured: a unit frozen at −1200 W beside a healthy +900 W sibling yields `circulating_w` = **1800 W against the 700 W floor, 2.6× over**, with no gate armed. Found in review; part 9's S2 check asserts only `not stale` and part 4 pairs the frozen unit with a RESTING sibling, so neither graded the sentence |
+| 3 | **miss — the largest** | a dead publisher whose last values **alternate**, or a cache replaying two old samples, never starts the unchanged clock at all | **this gate detects a value that STOPPED; it cannot detect a value that is WRONG.** Nothing in this add-on can. TEL-06's arrival stamp inside the firmware is the only layer that could |
+
+Recorded because it looks like a survivor and is not: a publisher failure that
+freezes **both** registers is caught on both units independently, on each unit's
+own command travel and each unit's own number.
+
+---
+
+## 7. Mutation record — 2026-09-06
+
+`tools/mutation_run.sh`'s rule, honoured on every run: purge first (count printed,
+`0` remaining), tree mounted `:ro`, `python3 -B`, fingerprint the tree, **and
+fingerprint again after the revert**. Clean tree `app/freshness.py`
+`sha256:f40fa3e8819014ce` / 20,065 B, `app/inverter.py` `7e760c6e8cdfa5b7` /
+30,778 B, `app/main.py` `7d7ff4ba0697ea64` / 238,535 B. Each mutant graded by
+`test_freshness.py` + `test_inverter.py`.
+
+| # | mutation | file | Δ B | result |
+|---|---|---|---|---|
+| M0 | none (control) | freshness | +0 | **green** — the harness is not red on everything |
+| M1 | `reading()` returns `self.last` unconditionally | freshness | −24 | red, 3 named checks |
+| M2 | drop the command-travel term | freshness | −59 | red |
+| M3 | drop the magnitude term | freshness | −54 | **SURVIVED**, then red — §2.2. This is the finding |
+| M4 | latch never holds | freshness | +13 | red, 3 named checks |
+| M5 | bound 90 s (slower than both consumers) | freshness | **+0** | red |
+| M6 | bound 10 s (under the physical floor) | freshness | **+0** | red |
+| M7 | `MOVE_W` 700 W | freshness | **+0** | red, on part 6's `config.yaml` pin |
+| M8 | the wiring in `_read_unit` removed | main | −5 | red, 3 named checks |
+| M9 | reset the unchanged clock on every arrival (value-stamped) | freshness | −43 | red |
+| M10 | `standing_w()` drops `last_write` | inverter | −73 | red, and takes `test_inverter.py` with it |
+| M11 | `standing_at_change` refreshed on every arrival | freshness | +121 | ⚠️ **DISCOUNTED — the mutant does not parse** |
+| M11b | the same defect, written parseably | freshness | +105 | red |
+| M12 | `BOUNDS["soc"].wired = True` — the table lies | freshness | −1 | red |
+| M13 | the wrong signal submitted (`inv.soc` for `inv.batt`) | main | +4 | red, and `test_inverter.py` too |
+| M14 | one `Freshness` shared by every unit | inverter | +29 | red |
+| M15 | latch cleared by a failed read | freshness | +31 | **SURVIVED**, then red — see below |
+
+⚠️ **M5, M6 and M7 are `+0 B`, which MUTATION.md names as the risky delta.** All
+three are **reds**, which is the direction stale bytecode cannot fabricate, and
+every run purged with the count printed and graded a `:ro` tree that physically
+cannot hold a cache.
+
+⚠️ **M11 IS NOT A RESULT AND IS NOT COUNTED.** Its edit dedents a statement into
+the middle of an `if` body, so the module raises `IndentationError` at line 312
+and both files go red without a single check being evaluated. Verified by
+`ast.parse` rather than assumed. **M11b** is the same defect written so it
+parses, and it is a real red.
+
+### The two survivors, and what each one taught
+
+**M3, the magnitude term** — see §2.2. Two terms of a conjunction that move
+together in every fixture are one term as far as the checks are concerned.
+Recorded as `MUTATION.md` **habit 17**, twelfth instance of "a check whose DATA
+cannot reach the failure it names".
+
+**M15, the latch cleared by a failed read** — found only because the sweep went
+looking for what the checks would NOT see. No fixture had ever injected a read
+failure *while latched*, and it matters: a stale verdict stops the site, the site
+is then commanded 0 W, and one unreachable-Home-Assistant read would drop the
+latch into a state where the conjunction is no longer armed — so the held
+−1200 W would come back to the consumers on the very next successful read. Part 4
+now grades exactly that and M15 is red.
+
+### And one process defect worth more than the ledger
+
+One mutation's container run overran a two-minute command budget and the wrapper
+was killed **between the edit and the revert**, leaving `app/freshness.py`
+mutated on disk. Nothing announced it; the next mutation's harness cheerfully
+fingerprinted and graded the mutant *plus* a second mutation. It was caught by
+comparing the tree fingerprint against the recorded clean one, restored, and
+verified back to byte and `sha256` before anything else ran. Same defect as stale
+bytecode, different cause. Recorded as `MUTATION.md` **habit 18**: *fingerprint
+after the revert, not only before the run.*
+
+### A third, in this file's own fixture
+
+M2 originally reported "red" with **no named check behind it**. The mutant makes
+the FRESH run stale, so `test_freshness.py`'s own diagnostic
+`print(f"… {sorted(set(_fresh_read))}")` raised `TypeError` comparing `None` with
+a float **before check one ran**. MUTATION.md's reporting rule is *"which suite
+went red, and on which named check"*, and a print that can crash first destroys
+exactly that. Sorted with `key=str` now; M2 reports its check.
+
+### Re-verified at the committed head
+
+The 16-row sweep above graded `test_freshness.py` as it stood when each mutation
+ran; the two closures (M3's part-4 check, M15's failed-read check), the `key=str`
+fix and the wall-clock hardening all landed afterwards. So six mutations were
+re-run against **the exact tree that is committed** —
+`test_freshness.py sha256:a62f3e1f1ac856cf`, 44,913 B:
+
+| # | result at head |
+|---|---|
+| M0 control | **green** |
+| M2 drop the command-travel term | red, on part 1's "FRESH AND UNCHANGED is not stale" |
+| M3 drop the magnitude term | red, on part 4's magnitude check |
+| M8 wiring removed | red, on three named checks in parts 2 and 3 |
+| M11b `standing_at_change` drifts | red, on three named checks in part 1 |
+| M15 latch cleared by a failed read | red, on part 4's failed-read check |
+
+The other ten are unaffected by those edits: each is red on a check in parts 1,
+2, 4, 6, 7 or 9 that none of them touches, and a mutation red on one check
+cannot be made green by adding another.
+
+### The wall clock, which part 3 cannot avoid and therefore measures
+
+The freshness verdict runs on an injected monotonic clock and is deterministic.
+The sign watchdog inside `cycle()` cannot be injected, so part 3 runs against the
+real one — which is CI-06's failure mode exactly (`test_peakguard.py` answered
+two checks with the wall clock, flaked at ~20 %, and cost a wrong merge
+diagnosis). So the margin is measured and asserted rather than assumed:
+
+    gate closed after 0.61 s of WALL clock, against the 2 s watchdog window (3.3x margin)
+
+If a loaded machine ever narrows that, the check fails **naming the number**,
+which is the difference between "the box was slow" and "the code is broken".

goodwe_controller/DECISIONS/SAFETY-38-site-standing-pin.md

@@ -0,0 +1,925 @@
+# SAFETY-38 — pinning `site_standing`, the one quantity both site guards are asked about
+
+**Status: DECIDED 2026-09-05.** `app/main.py`'s
+`site_standing = float(sum(standing.values()))` is **correct and is not
+changed**. What this card adds is the thing it never had: a **behavioural**
+fixture whose per-unit shares **cannot** answer for the site, so that a change
+of *meaning* in that reduction goes red instead of green.
+
+Filed with SAFETY-38, card `6a9ac95f2b78646e5a76d2e9`. It is a **coverage**
+card: not one byte of `app/` moves.
+
+---
+
+## 0. The line, and its two consumers
+
+```python
+site_standing = float(sum(standing.values()))          # app/main.py:1598
+```
+
+`standing` is `{unit name -> the value THIS controller last put on that unit's
+setpoint entity}` — `inv.last_write`, i.e. the number **after**
+`clamp_to_rating()` has applied `max_w` and the device's own
+`[dev_min, dev_max]`. Two safety inputs are derived from it and nothing else in
+`cycle()` is:
+
+| consumer | where | what it does with it |
+|---|---|---|
+| **[[SAFETY-30]]**'s site sign detector | `self.site_sign_wd.evaluate(site_standing, self.grid, …)` (main.py:1619) | **latches and stops the whole site** when the total command opposes the meter for `site_sign_disagree_s` |
+| **[[SAFETY-18]]**'s freeze conjunction | `looks_frozen(unchanged_s, site_standing, max_w, …)` inside `peakguard.decide(frozen=…)` (main.py:1926) | takes the peak guard **blind** and files `floor_w = 0.0` — the battery may not import while the billed quarter is unmeasurable |
+
+Both are P0 paths. **Neither was pinned to the reduction.**
+
+## 1. What survived, and what the rescope measured
+
+The card opened with three demonstrated live mutants, all green across the whole
+suite. Re-measured in round 2 against `release/1.0` @ `86eaef2`:
+
+| mutation of `site_standing` | on release/1.0 @ 86eaef2 | closed by |
+|---|---|---|
+| `list(standing.values())[0]` — one unit's share | **SURVIVES**, full suite 21/21 green | part 9a + 9b (this card) |
+| `sum(...) / max(1, len(standing))` — the mean | **SURVIVES**, full suite 21/21 green | part 9a + 9b (this card) |
+| `max(standing.values(), key=abs)` — the largest share | **SURVIVES**, full suite 21/21 green | part 9a + 9b (this card) |
+
+### ⚠️ ROUND 1 SAID `[0]` WAS ALREADY CLOSED BY SAFETY-32. THAT WAS FALSE.
+
+Round 1 of this card recorded `[0]` as **CAUGHT by SAFETY-32's package-wide
+structural pin**, wrote that claim into four places, and told future authors
+*"DO NOT RE-COVER THAT ONE HERE"*. It is wrong, and **how** it went wrong is the
+part worth keeping.
+
+**How the error was made.** The mutation was measured **once**. That single run
+happened to hit `test_peakguard.py`'s [[CI-06]] flake — a **measured ~20%**
+false-red rate — and the red was recorded as a **mutation kill**. Nothing else
+was checked, because a red is the answer you are hoping for and it did not look
+like it needed a second run.
+
+**The correct measurement.** On `release/1.0` @ `86eaef2` carrying **only** the
+`[0]` edit (+4 bytes, re-read from disk, bytecode purged by
+`tools/mutation_run.sh`): the **full 21-file suite is green**, and
+`test_peakguard.py` run **five times in isolation** on that same mutated tree is
+**PASS PASS PASS PASS PASS**. The mutation **survives**. (The reviewer's own
+independent re-measurement of the same tree hit the flake once —
+PASS PASS PASS FAIL PASS — which is the same verdict plus a live demonstration
+of the mechanism that produced the original error.)
+
+**Why SAFETY-32 cannot see it, read off 12j's own enumeration rather than
+argued.** Part 12j taints names *bound* to roster-carrying values and lists
+*accumulated* in a loop over one. `standing` is neither: it is a dict created
+empty at `main.py:1554` and filled by **subscript assignment**
+(`standing[inv.name] = stood`) inside the roster loop, and a subscript store is
+not a binding 12j follows. So `standing` never enters its taint set and
+`sum(standing.values())` is **not a roster site** at all. Run 12j against a tree
+carrying the `[0]` mutation and its enumeration lists `main.py:1553`, `1555` and
+`1690` — the three `self.inverters` sites bracketing this code — and **not
+`1599`**. No shape pin reaches this line; only the behavioural fixture below
+does.
+
+**The rule this cost.** `test_peakguard.py` flakes at a measured ~20%. A single
+red from it proves nothing. Re-run it in isolation **at least five times** and
+**name the failing check** before believing any red from it. This card is the
+**third** measurement CI-06 has corrupted.
+
+SAFETY-32's own disclosed blind spot says why the other two were always out of
+reach:
+
+> *SEMANTICS. `min` → `max` → the mean are edits invisible to any shape pin,
+> permanently. Only the behavioural sets can see them.*
+
+`sum` → mean and `sum` → `max(key=abs)` are **semantic**: identical shape,
+different meaning. **No shape pin will ever close them.** That disclosure was
+accurate, and is now confirmed by measurement rather than taken on trust.
+
+`[0]` is the one that *looks* structural and therefore *looks* covered — and
+that appearance is exactly what produced the false attribution above. It is
+out of reach here for a different reason from the other two: not because the
+shape is invisible, but because **the value never becomes a roster** in the
+analysis's eyes. All three are closed by the same behavioural fixture, and
+**all three needed it.**
+
+## 2. Why the suite could not see it — habit 4, inside the site half of the very card that names it
+
+`test_watchdog.py`'s `_sign_site` is the **only** N≥2 site fixture in the
+repository. It runs at `site_sign_disagree_w: 320` with shares of roughly
+−2500 W **each**. Every one of them is individually far over the gate, so on
+those numbers
+
+```
+sum  =  −5000 W   over        mean =  −2500 W   over        max =  −2500 W   over
+```
+
+— **all three reductions agree**, and a check whose two candidate answers happen
+to be equal cannot observe a change that swaps them. That is `MUTATION.md`'s
+third failure mode, and this is its ninth instance.
+
+At a roster of **one** it is not a fixture defect but arithmetic:
+`sum == mean == max == the one share`, identically, so all three mutations are
+genuinely **equivalent** on a shipped install. No N=1 fixture can ever separate
+them; §3c asserts that rather than leaving it to the reader.
+
+## 3. The fixture, and the numbers it is built on
+
+Two **simulated** units rated 220 W and 280 W, both obeying exactly, inverted
+gain, house importing 2000 W. Both stand at their own rails, so `standing` is
+`{-220, -280}` in roster order and the meter reads +2500 W.
+
+| reduction | value | vs the SHIPPED 300 W gate |
+|---|---|---|
+| `sum` | **−500 W** | **OVER** → trips |
+| `sum / len` (the mean) | −250 W | under → silent |
+| `max(…, key=abs)` | −280 W | under → silent |
+| `list(…)[0]` | −220 W | under → silent |
+
+**Four distinct magnitudes — 500, 250, 280, 220 — of which exactly one clears
+the gate.** The asymmetry is load-bearing twice: equal shares would collapse
+mean, max and first onto one number, and putting the **smaller** unit first is
+what keeps `[0]` distinct from `max(key=abs)`. The gate is left at its shipped
+default so the fixture is graded against the magnitude an install runs; only the
+**hold** is shortened (325 s → 2 s), because the hold is a wall clock and the
+campaign behind 325 s is measured on the rig, not here.
+
+⚠️ **220 W and 280 W are SIMULATED ratings chosen for that arithmetic and for
+nothing else.** They are not measurements. In particular they are **not**
+inverter B, which does not physically exist; B is a GW5048D-ES, serial
+`55048ESU22AW0992`, **4600 W from its datasheet** (`goodwe/NOTES.md` §1.1b).
+
+### 3a. The site sign detector
+
+Shipped tree: the site latches, commands 0 W on every inverter, and the sentence
+an operator reads is
+`SIGN_DISAGREEMENT: commanded -500 W against a meter reading +2500 W …`. No
+per-unit watchdog trips — every unit is faithfully executing its share, which is
+the asymmetry the site detector exists for.
+
+Under the mean and under `max(key=abs)`: **nothing trips, ever.** The reviewer's
+tree was still commanding −500 W of charge into a +2500 W import at t = 595 s
+with `following=True`.
+
+Two counterfactuals sit beside it so the trip is attributable:
+
+* the **same** inverted-gain site whose shares sum to −250 W — under the gate —
+  does **not** trip, so the trip above is the sum crossing 300 W and not the
+  mere presence of a second inverter;
+* a site whose **device range is narrower than `max_w`** asks for −500 W while
+  only −250 W stands, and does **not** trip — see §5.
+
+### 3b. The second consumer, covered rather than scoped out
+
+`site_standing` is also `looks_frozen()`'s `commanded_w`. The same
+discrimination applies at a different threshold: the site rail is
+`RAIL_FRAC * site_max_w` = 0.95 × 500 = **475 W**.
+
+| reduction | value | vs the 475 W rail |
+|---|---|---|
+| `sum` | **500 W** | **RAILED** → `BLIND_FROZEN`, `floor_w = 0.0` |
+| the mean | 250 W | under → silent |
+| `max(…, key=abs)` | 280 W | under → silent |
+| `list(…)[0]` | 220 W | under → silent |
+
+The sign is flipped from §3a on purpose: the gain is the **shipped positive**
+one and the frozen meter reads import, so the site *discharges* +500 W against a
++2500 W import — the two agree in sign, SAFETY-30 has nothing to say, and this
+half grades SAFETY-18 alone. Reusing §3a's inverted gain would have the site
+sign latch park everything at 0 W, and the freeze conjunction could then never
+be true: a check measuring the *other* guard's remedy.
+
+⚠️ **The open quarter is backfilled with the same stuck reading, and that is
+not decoration.** Without it the block is mostly uncovered, `blindness()`
+answers `BLIND_COVERAGE`, and the mutant reaches *the same action by a different
+route* — a check on the action alone could not then see the difference it names.
+Seeded, the measurement is honest:
+
+* shipped: `blind = BLIND_FROZEN`, `floor_w = 0.0` — no charging while the
+  billed quarter is unobservable;
+* both mutations: **not blind at all**, `floor_w = None` — the site may go on
+  importing through a quarter whose billed average cannot be measured. That is
+  the capacity-tariff hazard SAFETY-18 exists for, silently disarmed.
+
+The counterfactual comes from the **same run**: on the earlier cycles the
+command had not yet reached the rail and the guard did not report SAFETY-18,
+with the meter equally frozen throughout — so the verdict is produced by the
+command magnitude `site_standing` carries and not by `unchanged_s` alone. A low
+gain (0.05, the schema floor) is what buys those below-the-rail cycles.
+
+### 3c. At N=1, nothing changes — asserted
+
+A real one-inverter controller is driven through the same frozen-meter
+scenario. Its `standing` has a single entry, so `sum`, the mean,
+`max(key=abs)` and `[0]` are printed and asserted to be **one number**; the
+site sign detector is still absent (part 7 counts the calls on the object); and
+SAFETY-18 still reaches `BLIND_FROZEN` on that same value. The claim "the
+shipped install is unaffected" now rests on the roster rather than on the
+reader.
+
+## 4. Mutation ledger
+
+Every run: a **fresh full-repo copy**, `__pycache__` and `*.pyc` excluded,
+mounted `:ro`, graded by `tools/mutation_run.sh` (which purges, prints the tree
+fingerprint, and verifies no cache appears during the run). The mutated line was
+**re-read from disk** after the edit and the byte delta printed. Shipped
+`app/main.py` is 234 542 bytes at `86eaef2`.
+
+| # | mutation of `site_standing` | Δ bytes | verdict |
+|---|---|---|---|
+| M1 | `sum(...) / max(1, len(standing))` — the mean | +24 | **RED** |
+| M2 | `max(standing.values(), key=abs)` — largest share | +9 | **RED** |
+| M3 | `list(standing.values())[0]` — one share | +4 | **RED** — and **survives on release/1.0**, see §1 |
+| M4 | `min(standing.values(), key=abs)` — smallest share | +9 | **RED** |
+| M5 | `sum(abs(v) for v in ...)` — magnitude, sign lost | +16 | **RED** |
+| M6 | `-sum(standing.values())` — sign flipped | +1 | **RED** |
+| M7 | `float(self.target)` — the arbiter's site target | **−11** | **was a SURVIVOR — now RED**, see §5 |
+| M8 | `sum(standing.values()) / 2.0` | +6 | **RED** |
+| M9 | `sum(standing.values()) * 2.0` | +6 | **RED** |
+| M10 | `sorted(standing.values())[-1]` — largest signed | +7 | **RED** |
+| **M11** | **argument SWAP** at the SITE call site: `evaluate(site_standing, self.grid, …)` → `evaluate(self.grid, site_standing, …)` (main.py:1620) | **0** | **was a SURVIVOR in round 1 — now RED**, see §4a |
+| **M12** | **argument SWAP** at the PER-UNIT call site: `evaluate(stood, against, …)` → `evaluate(against, stood, …)` (**main.py:1560**) | **0** | **was a SURVIVOR in round 2 — now RED**, see §4c |
+
+**Every one of the ten `site_standing` entries is red in `test_watchdog.py`.** Re-measured in round 2
+on `release/1.0` @ `86eaef2` (where `app/main.py` is 234 542 bytes, 2 022 more
+than the `f72c48d` the round-1 figures were taken on): all ten still red, at the
+byte deltas in the table, each on a fresh copy with the edit re-read from disk.
+Adding assertions cannot turn a red green, so those verdicts carry forward to
+the round-3 tree unchanged.
+
+### ⚠️ ROUND 2 SAID THREE OF THESE SURVIVED. **EIGHT DID.**
+
+Round 2 wrote: *"Before part 9 existed, three of these left the whole suite
+green — M1, M2 and M3 — and the remaining seven were caught by SAFETY-30's own
+N≥2 checks."* Round 1's wording was vaguer and harmless; naming three made it
+**specific and wrong**, and it is the same species of error the round was
+written to fix — **a survivor recorded as a kill**. This file contradicted it
+three times on its own pages: the ledger row calls M7 *"a SURVIVOR — now RED"*,
+§5 says M7 survived the whole suite, and `CHANGELOG.md` says so too.
+
+**Re-measured in round 3, one mutation at a time, on clean `release/1.0` @
+`bbc903b`** — a fresh copy each, bytecode purged (`0` remaining, printed), the
+line re-read from disk, byte delta **and** `app/main.py` fingerprint printed,
+mounted `:ro`, and the **FULL 21-FILE SUITE** run each time rather than
+`test_watchdog.py` alone. (`release/1.0` has since moved on to `9e42cec`, which
+merged [[CI-06]]; that commit touches `test_peakguard.py` and `CHANGELOG.md`
+only, neither of which grades `site_standing`, so the ten verdicts below stand
+on the tree they were taken on and this branch is rebased onto the newer tip.)
+
+| # | Δ bytes | fingerprint of `app/main.py` | suite before part 9 |
+|---|---|---|---|
+| M1 | +24 | `362374cfb6486378` | **21/21 PASS — SURVIVOR** |
+| M2 | +9 | `86573e7494f1c933` | **21/21 PASS — SURVIVOR** |
+| M3 | +4 | `59fa8815e6fda4cf` | **21/21 PASS — SURVIVOR** |
+| M4 | +9 | `43d852be3037f861` | **21/21 PASS — SURVIVOR** |
+| M5 | +16 | `58d26de82af29a1a` | **RED** — `test_watchdog.py`, 3 checks |
+| M6 | +1 | `407ddb5f375cc217` | **RED** — `test_watchdog.py`, 3 checks |
+| M7 | **−11** | `2a635a4eca0a790d` | **21/21 PASS — SURVIVOR** |
+| M8 | +6 | `b21eed89ff4c9240` | **21/21 PASS — SURVIVOR** |
+| M9 | +6 | `0973d3caf680db65` | **21/21 PASS — SURVIVOR** |
+| M10 | +7 | `0e7b7a4fed7787d0` | **21/21 PASS — SURVIVOR** |
+
+**So: EIGHT of the ten left the whole suite green, and TWO were caught** — not
+three and seven, and not the four and six a reviewer proposed either. The
+correct sentence is: *before part 9 existed, eight of these ten left the whole
+21-file suite green, and the only two SAFETY-30's own N≥2 checks caught were M5
+and M6.*
+
+**⚠️ AND THE TWO THAT WERE CAUGHT ARE CAUGHT FOR A REASON THAT MAKES THE CARD'S
+CASE RATHER THAN WEAKENING IT.** M5 (`sum(abs(v) …)`) and M6 (`-sum(…)`) are
+the only two entries in the table that **reverse the SIGN** of `site_standing`.
+Every other entry changes only its **magnitude** — and `_sign_site`, the suite's
+only N≥2 site fixture before this card, runs shares of about **−2500 W each**
+against a **320 W** gate. `sum`, the mean, `max(key=abs)`, `min(key=abs)`,
+`sorted(...)[-1]`, `[0]`, `self.target`, half the sum and twice the sum all land
+on **−2500, −2500, −2500, −2500, −2500, −2500, −2500, −1250 and −5000 W**: nine
+different numbers, all on the **same side of the same threshold**. The three
+checks that fired on M5 and M6 grade *"the site trips and no unit does"*, the
+claim it trips through, and where the latch is written — none of them grades the
+**quantity**, and the sign flip reaches them only because it stops the trip
+happening at all.
+
+That is the whole thesis of this card measured rather than argued: **the
+pre-existing coverage could see a sign, and nothing else.** Part 9's fixture —
+per-unit shares each **below** the gate whose **sum** clears it — is the only
+arrangement in which the magnitude is load-bearing, and it is what takes the
+other eight red.
+
+⚠️ **ONE FALSE RED, AND IT IS [[CI-06]]'s.** In the batch run M10 also reported
+`FAIL test_peakguard.py`. Re-run in isolation **three times** and once more
+through `tools/mutation_run.sh` — **four clean passes, zero failures**. The
+batch script had discarded the failure detail, so the failing check cannot be
+named here; what can be said is that the red did not reproduce in four attempts
+and that **no claim in this card rests on it**. `test_peakguard.py` is the file
+CI-06 records as flaky, and this is the behaviour it records. Believe no red
+from it without three isolated re-runs.
+
+⚠️ **ROUND 3 CAN NAME ONE, AND IT IS THE SAME FILE.** Round 3's own batch — the
+ten full-suite runs above, plus §7's sibling swaps — produced **no** red from
+`test_peakguard.py` on M10 or on any other ledger entry. It produced exactly one
+elsewhere, on a **`static_tariff.py`-only** edit (§7b, A4), and this time the
+failing check *was* captured: *"one cycle of the intent form is exactly the
+delivered form plus the command standing on the wire"* — which is CI-06's
+**mechanism 1 by name**, the cross-time projection. `test_peakguard.py` then
+passed **four for four** in isolation on that same tree. That is the first time
+this card has been able to put a name to one of these reds, and it is the name
+CI-06 predicts.
+
+⚠️ **M3 IS NOT "FOR COMPLETENESS", AND ROUND 1 SAID IT WAS.** Round 1 recorded
+M3 as already closed structurally by SAFETY-32 and disclaimed it. §1 above has
+the correction and the mechanism: `[0]` **survives** a full green 21-file suite
+on `release/1.0` @ `86eaef2`, because `standing` is a dict filled by subscript
+assignment and never enters 12j's taint set. **M3 is a real kill by this card's
+fixture and by nothing else in the repository.** It is claimed here.
+
+### 4a. ⚠️ The zero-byte survivor one line below the one this card pinned
+
+Round 1 pinned the **value** `site_standing` and never pinned **where it goes**.
+Swapping the detector's first two arguments at `main.py:1620` is a **zero-byte**
+edit — the same characters, reordered — and it left the round-1 tree **21/21
+green**.
+
+What it costs is the banner. `SignWatchdog.evaluate()` formats
+`commanded_w` first and `against_w` second, so under the swap part 9a's own
+output reads:
+
+```
+SIGN_DISAGREEMENT: commanded +2500 W against a meter reading -500 W for 2 s …
+```
+
+The site is standing at **−500 W of charge into a +2500 W import** and the
+**latching, site-stopping** banner tells the operator **the exact opposite** —
+which instrument read what, inverted. `watchdog.py:658-665` names this failure
+in its own words: *"a false statement about which instrument produced the
+evidence, on the one line somebody woken by this alarm reads first."*
+
+**Why round 1's check could not see it, and this is the general lesson.** It
+asserted
+
+```python
+f"{sum(_share38):.0f} W" in _c38.site_sign_wd.reason
+```
+
+— that `"-500 W"` appears **somewhere** in the sentence. Under the swap it still
+does: in the **meter slot**. A substring test cannot reach a failure that is
+purely **positional**, and round 1's own comment claimed the opposite ("*would
+put a different number in the store, the action log and the banner, and this is
+where that shows*"). It shows the **number**, never its **position**. This is
+MUTATION.md's *"a check whose data cannot reach the failure it names"*, in the
+card that exists to complain about exactly that.
+
+**The fix is one line and touches no `app/` code** — assert the **ordered
+pair**:
+
+```python
+f"commanded {sum(_share38):+.0f} W against a meter reading "
+f"{_mid38['grid']:+.0f} W" in _c38.site_sign_wd.reason
+```
+
+Measured: with that line, M11 is **red in `test_watchdog.py` and green in the
+other twenty files** — one file, one check.
+
+### 4b. Claim wiring, re-measured rather than assumed
+
+Round 1's reviewer disclosed it had **not** mutated the arbiter claim wiring or
+[[SAFETY-31]]/circulation. Both were mutated in round 2. Both are **zero-byte**
+edits to `arbiter.CLAIM_SCOPE`:
+
+| # | mutation | Δ bytes | verdict |
+|---|---|---|---|
+| W1 | `"sign_site": SCOPE_SITE` → `SCOPE_UNIT` | **0** | **RED** — `test_watchdog.py` (parts 5 **and 9a**), `test_arbiter.py`, `test_peakguard.py` |
+| W2 | `"circulation": SCOPE_SITE` → `SCOPE_UNIT` | **0** | **RED** — `test_watchdog.py`, `test_arbiter.py`, `test_peakguard.py` |
+
+Part 9a's *"…and it stops the WHOLE site, through the `sign_site` claim by name"*
+is one of the two checks that kills W1, so this card contributes to that
+coverage rather than merely inheriting it. **W2 is caught entirely by
+pre-existing checks** — SAFETY-38 adds nothing to circulation, and does not
+claim to.
+
+### 4c. ⚠️ The SAME zero-byte defect one call site over — and it is the one the shipped install can see
+
+Round 2 closed §4a by asserting the ordered pair on the **site** banner at
+`main.py:1620`. It did not touch `main.py:1560`, the **per-unit** call, and the
+identical swap there —
+
+```python
+if inv.sign_wd.evaluate(stood, against, self.following, now)      # shipped
+if inv.sign_wd.evaluate(against, stood, self.following, now)      # M12
+```
+
+— left the round-2 tree **21/21 green**. Measured: `app/main.py` 234 542 bytes
+before and after, **Δ 0 bytes**, fingerprint `61aa413f…` → `e57e6026…`, bytecode
+purged, tree mounted `:ro`, the line re-read from disk.
+
+**Nothing behavioural can catch it, and that is structural rather than
+unlucky.** `watchdog.disagrees()` is *symmetric* in its first two arguments —
+`commanded_w * against_w < 0`, with an `abs()` gate on **both** — so the swap
+cannot change a single trip decision on any input. What it changes is the
+**sentence**. Measured by diffing the suite's own printed banners between the
+round-3 tree and the same tree carrying only M12: **9 emitted banner lines
+invert, in 3 distinct sentences.**
+
+```
+shipped:  SIGN_DISAGREEMENT: commanded -2000 W against a meter reading +2000 W …
+M12:      SIGN_DISAGREEMENT: commanded +2000 W against a meter reading -2000 W …
+
+shipped:  … commanded +1000 W against its own measured power -1000 W …
+M12:      … commanded -1000 W against its own measured power +1000 W …
+
+shipped:  … commanded -2000 W against a meter reading +4000 W …      (the N=1 arm)
+M12:      … commanded +4000 W against a meter reading -2000 W …
+```
+
+**⚠️ AND IT IS WORSE THAN THE ONE ROUND 2 CLOSED.** Part 9c asserts the SITE
+detector is **not armed at a roster of one**, and inverter B does not physically
+exist. So on the shipped install the **per-unit banner is the only
+sign-disagreement sentence that can ever be printed** — in the action log, in
+`_LOG.error`, in `status_payload()`'s headline banner, and in `sign_reason`,
+which is persisted and read back after the restart the latch is designed to
+survive. Round 2 pinned the N≥2-only call site and left the shipping one open.
+
+**Closed by the ORDERED PAIR on both per-unit banners**, with both operands read
+off the **observed cycle** — `inv.last_write` and `inv.batt` off the objects the
+plant moved, never off the arguments the detector was handed, which would be
+comparing the swap against itself:
+
+* `test_watchdog.py` **part 3**, the N≥2 per-unit trip:
+  `f"commanded {stood:+.0f} W against its own measured power {meas:+.0f} W"`,
+  plus the persisted `unit/inverter-b/sign_reason` copy, plus a **precondition**
+  that the two operands are different numbers of opposite sign — without which
+  a transposition would produce the same string and the check would be
+  decoration;
+* `test_watchdog.py` **part 7**, the **N=1** controller-driven trip:
+  `f"commanded {stood:+.0f} W against a meter reading {grid:+.0f} W"`, plus the
+  namespaced key **and** the flat rollback mirror, plus the same precondition.
+
+**Measured after the fix: M12 is RED on four named checks in
+`test_watchdog.py` and GREEN in the other twenty files** — one file, four
+checks. M11 re-measured on the same tree: still red.
+
+**⚠️ Neither §6a nor MUTATION.md disclosed it.** §6a's "what was NOT closed"
+enumerated `circ_wd`, the eight other `CLAIM_SCOPE` entries, `actuator_of()`'s
+body and the `n_units > 1` guard — not this. MUTATION.md's own closing rule, in
+the file round 2 edited, is *"a variant is not covered because a near-miss of it
+is."* §7 is the enumeration that would have caught both instances at once.
+
+## 5. The survivor this card went looking for, and closed
+
+M7 is not one of the card's three. It was found by asking the question the
+recurring defect demands — *what mutation would my new checks NOT see?* — and it
+is the answer: **−11 bytes**, and it survived every check above **and the whole
+20-file suite**, because in every fixture built so far the arbiter's site target
+and the sum of what actually stands on the wire are **the same number**.
+
+They are not the same number when a setpoint device's own reported range is
+narrower than its `max_w`. The `device` P_SAFETY claim is filed **per actuator**
+(`actuator_of("device", inv)`), so it bounds each unit's **share** and never the
+site target, and `clamp_to_rating()` clips again on the way out. On two units
+rated 220/280 W whose devices report ±120/±130 W, the site asks for **−500 W**
+and **−250 W** stands.
+
+Which one the guards mean is already written down, in both of them: SAFETY-02
+grades *"the command standing on the wire"*, and `looks_frozen()`'s docstring
+says `commanded_w` is *"the EMITTED setpoint — what the arbiter resolved and
+`write_setpoint()` put on the wire — not the loop's raw wish"*. [[SAFETY-20]] is
+the whole card about the difference. Those sentences are now made to bite: on
+the site target the detector fires on a site standing at −250 W against a
++2250 W meter — **under its own 300 W gate** — which is a latching, site-wide
+false trip on an install whose inverters simply report a narrower range than the
+operator typed.
+
+## 6. Honest gaps
+
+* **A mutation that changes the SIGN CONVENTION of `standing` itself** — i.e. in
+  `main.py`'s `stood = inv.last_write if inv.last_write is not None else
+  inv.target`, not on the reduction line — is **not** in this ledger. It is a
+  different line and a different card; §3a's obedience precondition would see
+  some of it, but that is not a measured claim and is not made here.
+* **The freeze half is graded at ONE roster length (2) and one rail.** The
+  `RAIL_FRAC` constant, `rail_ceiling_w()`'s device-bound conjunction and
+  `rail_unreachable()` are `test_freeze.py`'s subject and are untouched here.
+* **The site hold is 2 s, not the shipped 325 s.** The window's derivation is a
+  rig campaign (`DECISIONS/SAFETY-30-per-unit-sign.md` §3B) and this file does
+  not re-grade it. The **gate** is the shipped 300 W, which is the coordinate
+  this card is about.
+* **Everything about inverter B here is simulated and labelled so.** No number
+  in this document or in the fixture is a measurement of a device that does not
+  yet exist.
+
+### 6a. Round 2: what was closed, and what was NOT
+
+Round 1's reviewer disclosed that it had not mutated SAFETY-31/circulation, the
+arbiter claim wiring, or ledger entries M4/M5/M6/M8/M9/M10. Enumerated, with the
+gaps left open stated rather than rounded off:
+
+**Closed in round 2 (measured, on `86eaef2`, bytecode purged, edit re-read from
+disk, byte delta printed):**
+
+1. **M11**, the zero-byte argument swap — §4a. Red on one named check.
+2. **M3**, the `[0]` reduction — re-measured, **survives on release/1.0**, closed
+   by part 9a and 9b. The false attribution corrected in all four places it was
+   committed: this file §1 and §4, `CHANGELOG.md`, and `test_watchdog.py`'s part
+   9 header (which previously *instructed future authors not to re-cover it*).
+3. **M1, M2, M4, M5, M6, M7, M8, M9, M10** — every ledger entry re-run
+   independently in round 2 rather than carried forward from round 1's report.
+   All ten red; M1/M2/M4 re-run in the exact wrapped form the table records so
+   the byte deltas are the table's own (+24/+9/+9).
+4. **W1**, `sign_site` claim scope — §4b. Zero bytes, red, part 9a among the
+   killers.
+5. **W2**, `circulation` claim scope — §4b. Zero bytes, red, but **entirely on
+   pre-existing checks**.
+
+**NOT closed, and not claimed:**
+
+* **SAFETY-31's `circ_wd` detector itself** — its threshold, its hold, its
+  `circulating_w()` reduction over the roster. Only its **claim scope** was
+  mutated (W2), and that kill belongs to checks this card did not write.
+  Circulation's own behavioural coverage is `test_watchdog.py` part 4's and is
+  untouched here.
+* **The other eight `CLAIM_SCOPE` entries** — `loop`, `peak`, `arbitrage`,
+  `safety` (site) and `device`, `supervised`, `failsafe`, `maintenance` (unit).
+  `CLAIM_SCOPE` has ten entries; only the two named above were mutated. `test_peakguard.py` part 10f grades the
+  classification statically; that is a different instrument and this card did
+  not re-measure it.
+* **`actuator_of()`'s own body** and the `n_units > 1` guard on the `sign_site`
+  append at `main.py:1764` were **not** mutated.
+* **The ten ledger mutations were re-graded against `test_watchdog.py` only.**
+  The "green in the other twenty files" half of the round-1 claim was
+  re-verified on `86eaef2` for **M3** and **M11** (both full 21-file runs) and is
+  otherwise carried forward from round 1's measurement on `f72c48d`. It is a
+  weaker statement than round 1 made and is written down as such.
+  ⚠️ **Round 3 closed the other half of this**, but only in the *before*
+  direction: all ten were re-run on clean `release/1.0` @ `bbc903b` under the
+  **full 21-file suite** to establish which of them the pre-existing coverage
+  could see — see §4's ⚠️ paragraph, and the answer was **eight survivors, not
+  three**. The *after* direction — "each of the ten is red in
+  `test_watchdog.py` and green in the other twenty **on the round-3 tree**" —
+  is still measured end-to-end only for **M3, M11 and M12**. For the other
+  seven, "red" carries forward from round 2 (which adding assertions cannot
+  undo) and "green elsewhere" carries forward from round 1.
+* **`test_peakguard.py`'s CI-06 flake is not fixed by this card** and is not
+  this card's subject. It is *characterised* here (five isolated runs on the M3
+  tree, all PASS) only far enough to overturn the false kill it produced.
+
+### 6b. Round 3: what was closed, and what is still open
+
+**Closed in round 3:**
+
+1. **M12**, the zero-byte argument swap at the **per-unit** call site
+   `main.py:1560` — §4c. It was a survivor of the round-2 tree at **21/21
+   green**, and it is the **only** sign-disagreement banner a shipped
+   one-inverter install can print. Red on four named checks, green in the other
+   twenty files.
+2. **The ledger arithmetic in §4**, which round 2 made specific and wrong. See
+   §4's own ⚠️ paragraph: re-measured mutation by mutation on clean
+   `release/1.0` @ `bbc903b`, full 21-file suite each time.
+3. **The family itself is now enumerated by machine** —
+   `tools/symmetric_message_scan.py`, §7 — rather than by hand for a third time.
+
+**Open, named, and NOT claimed:**
+
+* **A3 and B1** — the only two status-page rows in which the freeze detector
+  ever names a device range: the **NOT COVERED** row and the **armed** row's
+  "below max_w because …" clause. `rail_unreachable()`'s `dev_min`/`dev_max` at `main.py:3208` and the
+  literal `f"only {inv.dev_min}...{inv.dev_max} W"` at `main.py:3231`. Both
+  measured: **0 bytes each, 21/21 green each.** Real, open members of the
+  family. They are **status-page rows rather than latching alarms**, and closing
+  them wants a fixture with a device whose two bounds are **asymmetric** — every
+  fixture in this repository uses `±d`, so the transposition is currently
+  invisible by construction — which belongs to `test_freeze.py`'s card, not to
+  this one.
+* **Twelve census-B sites** (§7c, B2–B12) determined unpinned at the **source
+  level** — the distinguishing literal appears in no `test_*.py` — and **not**
+  mutated. Weaker evidence than A1–A4 and B1, and written down as such
+  — §7d says the same thing with the same list.
+* **B6**, SAFETY-31's `circ_reason`, is the same shape as the defect this card
+  closed for SAFETY-02/30 and is *also* persisted and re-read after a restart.
+  §6a already declines to touch `circ_wd`; §7d says what that costs.
+* Everything §6a lists stays open: `circ_wd`'s own thresholds, the eight other
+  `CLAIM_SCOPE` entries, `actuator_of()`'s body, and the `n_units > 1` guard.
+
+### 6c. Round 4: what was closed, and what is still open
+
+**The blocker round 3 shipped.** The enumeration read as complete and covered
+**one syntactic sink**. Every one of census B's 16 members was a sentence that
+is **appended, assigned, or passed as a log argument** (`problems.append`,
+`out.append({"text": …})`, `self.reason = …`, `_LOG.info`). **Not one was a
+sentence that is RETURNED.** Census A has a return bucket, but only for
+symmetric **parameters**, so a method formatting its **own attributes** and
+handing the string back was invisible to both — and `describe()` / `explain()` /
+the reason-builders are exactly where this codebase keeps its operator
+sentences. Worse than the gap: it was in **none of the five blind spots the tool
+prints about itself**. A tool that asserts a completeness it does not have is
+the recurring defect wearing a new hat.
+
+**Closed in round 4:**
+
+1. **`clamp.py:253` `ClampResult.describe()`**, pair `requested_w` /
+   `applied_w` — §7e C6. A survivor of the round-3 tree at **21/21 green**,
+   **0 bytes**. It is the §15 action-log row at `main.py:1366` **and** the
+   ClampWatchdog notification reason at `main.py:2452`; **no `test_*.py`
+   mentioned `describe()` at all.** Pinned on the ordered pair, on the
+   contiguous literal, at **both** consumers, with a precondition that the two
+   operands render differently — `test_clamp.py` part 6d. **4 checks red** under
+   the transposition.
+2. **`peakguard.py:493` `PeakDecision.explain()`**, pair `projected_w` /
+   `ceiling_w` — §7e C7. Same measurement: **0 bytes, 21/21 green**; the string
+   `"peak guard idle"` was in no `test_*.py`. Pinned on the decision and on the
+   shipped status row at `main.py:3313` — `test_peakguard.py` part 13. **3
+   checks red.**
+3. **`arbiter.py:264` (B12)** — the check whose **claim was wider than its
+   assertion**, carried forward from §7d. Measured this round rather than left
+   at source level: **0 bytes, 21/21 green** before, **`test_arbiter.py` red**
+   after. **2 checks red.**
+4. **The tool's sinks are now stated rather than implied.** It prints what it
+   scans as a MESSAGE, that it now scans the RETURN sink through the returning
+   method's call sites, and — the part that was missing — **an explicit list of
+   what it does not scan at all**, largest hole first.
+
+**⚠️ The correction round 4 owes the ticket.** The brief placed
+`PeakDecision.explain()`'s idle sentence at `main.py:3299/3302`. Those two lines
+are the **floor-limited** branch, where `explain()` returns `self.reason` before
+the idle literal is ever built. The idle sentence reaches the page at
+**`main.py:3313`** and the action log at **`main.py:1951`** (edge-logged, so it
+is the RELEASE edge that writes it). The pin is on 3313; 1951 is disclosed
+below, unpinned.
+
+**Open, named, and measured — see §7f for the ledger:**
+
+* **TEN further zero-byte survivors** found by the widened scan, each measured
+  at 21/21 green on this tree: **two** in `allocator.py`'s `UnitPlan.explain()`
+  (C1 :154, C2 :160), three in `arbiter.py`'s two `explain()`s (C4a, C4b :344,
+  C5 :392), two in `tariff.py` (C8, C9), two in `arbitrage.py`'s trade reasons
+  (B17, B18) and one in `main.py`'s SoC-floor notification (B19).
+  None is a control decision; every one is a sentence an operator reads.
+  ⚠️ **CORRECTED after review, and the error is worth keeping visible.** This
+  bullet first said "Nine" while listing eleven, and the CHANGELOG said eleven
+  while listing eleven — and BOTH counted `allocator.py:162` (C3) among the
+  survivors when §7f records it as a KILL, red in `test_alloc.py`. The
+  authoritative tables in §7e and §7f were right throughout; only the summary
+  sentences a reader actually relies on were wrong. That is this card's own
+  recurring defect in prose rather than in code: a claim wider than the
+  measurement beneath it. Arithmetic, from §7f: 14 measured = 10 surviving +
+  1 already caught (C3) + 3 caught by this round (C6, C7, B12).
+* **The action-log surface of the peak-guard idle line** (`main.py:1951`) is
+  not pinned. The status row (3313) is, and both come off the same `explain()`,
+  so the *sentence* is closed and the *second call site* is not — which is
+  precisely the distinction §4c was written about, recorded rather than assumed.
+* Everything §6a and §6b list stays open.
+
+## 7. The symmetric-predicate family — every call whose argument order is load-bearing for a MESSAGE
+
+**Why this section exists, and it is the most useful thing in the card.** Round 2
+pinned the operand order of `SignWatchdog.evaluate()` at `main.py:1620`. Round 3
+found the **identical zero-byte defect at `main.py:1560`**, one call site over —
+and that one is worse, because `test_watchdog.py` part 9c asserts the site
+detector is **never armed at
+a roster of one**, so on the shipped install the per-unit banner is the **only**
+sign-disagreement sentence that can ever be printed. Twice in one card the
+enumeration was written by hand and twice it was short. MUTATION.md habit 12: *a
+hand-written scope is the same defect as a hand-written fixture.* So the family
+is now **computed**, by `tools/symmetric_message_scan.py`.
+
+### 7a. What makes this family invisible, and why it is not a fixture problem
+
+Every other defect in this document is a fixture problem: *no fixture happens to
+separate the mutant from the shipped code.* Build the right fixture and it goes
+red. This one is not that.
+
+Where a callee is **symmetric** in two arguments, a swap at a call site cannot
+change **any** action on **any** input. `watchdog.disagrees()` is
+`commanded_w * against_w < 0` with an `abs()` gate on **both** sides: the
+product commutes and the two gates are the same gate. There is nothing for a
+behavioural check to observe, ever — **not "no fixture separates them" but no
+fixture *can*.** The only surface that moves is the **sentence**, and the only
+check that can see it is one asserting the **ordered pair** (MUTATION.md habit
+14) at **that** call site.
+
+Two consequences the earlier rounds got wrong:
+
+* **The unit of coverage is the CALL SITE, not the function.** `evaluate()`'s
+  operand order was pinned and the defect still shipped, because the pin was on
+  the *other* call.
+* **A behavioural suite is not weak evidence here, it is NO evidence.** "21/21
+  green" is what this mutation is *guaranteed* to produce. Measured, twice: M11
+  at `main.py:1620` on the round-1 tree, and M12 at `main.py:1560` on the
+  round-2 tree.
+
+### 7b. Census A — the callee formats its own parameters
+
+`tools/symmetric_message_scan.py` renames each parameter pair, erases every
+formatted string, canonicalises the commutative operators (`*`, `+`, `and`,
+`or`, `==`, `min`/`max`, iterated tuple literals) and compares the **bodies**;
+it iterates to a **fixpoint**, because the symmetry is usually one call deep —
+`evaluate()` is symmetric only *through* `disagrees()`, and a single pass
+reports an empty family on a tree whose answer is already known. It then
+classifies each sentence by **where it goes**.
+
+Fixpoint on this tree: **3 rounds, 17 interchangeable positional and 5 keyword
+pairs across 14 functions**. 45 parameter pairs reach a sentence; **8** are
+symmetric — **5** whose sentence goes only to an operator, and **3** whose
+sentence is the **return value** and therefore has to be classified by hand,
+because a returned string is sometimes a KEY and sometimes a SENTENCE.
+
+| # | scan row | pair | called at | swap costs | reaches an operator via | pinned? |
+|---|---|---|---|---|---|---|
+| **A1** | `watchdog.py:613` `SignWatchdog.evaluate()` | `(commanded_w, against_w)` | **`main.py:1560`** — per-unit, **and the N=1 detector** | **0 B** | `sign_reason` (persisted), the action log, `_LOG.error`, `status_payload()`'s headline banner | **YES — round 3.** `test_watchdog.py` part 3 (`its own measured power`) and part 7 (`a meter reading`), on the contiguous literal with both operands read off the observed cycle. **Measured: 0 B, red on 4 named checks, green in the other 20 files.** |
+| **A2** | same row, second call site | `(commanded_w, against_w)` | **`main.py:1620`** — site | **0 B** | `site_sign_reason`, the action log, the status page | **YES — round 2**, part 9a. Re-measured on the round-3 tree: still red. |
+| **A3** | `freeze.py:405` `FreezeWatchdog.evaluate()` and `freeze.py:311` `rail_unreachable()` — both symmetric through `rail_ceiling_w()`'s `for bound in (dev_min, dev_max)` | `(dev_min, dev_max)` | **`main.py:3208`** (and 1928, 2755, 3196, 3219) | **0 B** | the status page's `freeze detector: NOT COVERED — the setpoint device reports a range of …` row | **NO.** Measured: swapped at `main.py:3208-3209`, **0 bytes**, `main.py` fingerprint `61aa413f…` → `2305b560…`, **21/21 green**. Disclosed in §7d, not closed. ⚠️ `rail_unreachable()` is the row the scan puts in its **RETURN** bucket: its returned string is a **sentence**, not a key, so it is a family member after all — which is exactly why that bucket says *read by hand*. |
+| **A4** | `static_tariff.py:522` `_raise_gap()` | `(start, end)` | `static_tariff.py:509`, `:513` | **0 B** | the `ProfileInvalid` refusal an operator reads at startup | **YES — pre-existing.** Measured: both call sites swapped, **0 bytes**, `static_tariff.py` fingerprint `caef7fde…` → `50e9a768…`, **red in `test_static_tariff.py` on two named checks** (*"…and names the uncovered range so the operator can fix it"*, *"…and the refusal names the uncovered range"*), because `_hhmm(start)}-{_hhmm(end)` is asserted as the contiguous literal `"22:00-23:00"`. ⚠️ That batch run also reported `FAIL test_peakguard.py` on a `static_tariff.py`-only edit; the failing check is *"one cycle of the intent form is exactly the delivered form plus the command standing on the wire"*, which is [[CI-06]]'s **mechanism 1 by name**, and `test_peakguard.py` passes **four for four** in isolation on that same tree. No claim here rests on it. |
+| A5–A6 | `static_tariff.py:522` `_raise_gap()` | `(start, weekday)`, `(end, weekday)` | — | — | — | **not real — the scan's one over-report.** It erases the sentence, so it cannot see that `DAY_NAMES[start]` with `start = 1320` raises `IndexError`. A mixed-type pair fails loudly, which is the opposite of this family. |
+| A7–A8 | `store.py:177` `unit_key()`, `mqtt.py:222` `unit_state_key()` | `(unit, key)`, `(slug, key)` | many | 0 B | — | **not this family.** The formatted string is the **return value and it is a KEY**: a swap renames a store key and an MQTT topic, which is behaviour every ordinary check can see. MAINT-05 is the card about it. |
+
+### 7c. Census B — the caller builds the sentence
+
+Census A only sees a callee formatting its **own** parameters, which was gap 2
+of its own honest-gap list. The other half never crosses a function boundary:
+an operator sentence built where it is printed, interpolating two values that
+are **interchangeable by shape**. No predicate is involved at all, so census A's
+symmetry test has nothing to test. The scan pairs interpolated expressions that
+are **one leaf apart** — `inv.dev_min` / `inv.dev_max`, `cfg.min_w` /
+`cfg.hold_s` — which is exactly what a transposition swaps, and it keeps only
+sentences whose sink is a **message**: an f-string that becomes a URL or a store
+key is data, and a swap there is an ordinary behavioural change. **16 candidates** in round 3, every one of them a **zero-byte** edit — and **22** after round 4 widened the sink classifier (B17–B22 below):
+
+| # | site | pair | reaches an operator as | pinned? |
+|---|---|---|---|---|
+| **B1** | `main.py:3231` | `inv.dev_min` / `inv.dev_max` | status page, `… accepts only −120…130 W` | **NO — MEASURED.** Transposed in place, **0 bytes**, `main.py` fingerprint `61aa413f…` → `ac36a97b…`, purged, `:ro`, **21/21 green**. The row then tells the operator the device accepts `130…−120 W`. |
+| **B2** | `main.py:3362` | `inv.dev_min` / `inv.dev_max` | status page, `setpoint … (range −120…130 W)` | **NO** — the literal `setpoint … (range` is in no `test_*.py`. |
+| **B3** | `main.py:3435` | `sign_wd.cfg.hold_s` / `.cfg.min_w` | status page, `sign watchdog: armed (trips after 180 s opposed, both over 300 W)` | **NO** — `s opposed` is in no `test_*.py`. |
+| **B4** | `main.py:3460` | `site_sign_wd.cfg.hold_s` / `.min_w` | status page, the site sign row | **NO** — `armed against the sum` is in no `test_*.py`. |
+| **B5** | `main.py:3491` | `circ_wd.cfg.hold_s` / `.min_w` | status page, the circulation row | **NO** — `circulation watchdog: armed` is in no `test_*.py`. |
+| **B6** | `circulation.py:317` | `cfg.min_w` / `cfg.hold_s` | **`circ_reason` — persisted, and re-read after a restart** | **NO** — `test_watchdog.py` asserts only `"CIRCULATING_POWER" in reason`. **This is SAFETY-31's twin of the exact defect this card just closed for SAFETY-02/30**, on a string with the same persistence. |
+| **B7** | `main.py:2454` | `self.site_max_w` / `self.target` | the clamp action-log line | **NO** — `was clamped to` is in no `test_*.py`. |
+| **B8** | `main.py:3386` | `clamp_wd.engagements` / `.episodes` | status page, `engaged N time(s) in M episode(s)` | **NO** — `time(s) in` is in no `test_*.py`. |
+| **B9–B11** | `main.py:3169` (three pairs) | `p1.net_w` / `.samples` / `.parse_errors` | status page, the P1 row | **NO** — `P1 meter (` is in no `test_*.py`. |
+| **B12** | `arbiter.py:264` | `c.source` / `c.actuator` | `scope_errors`, the arbiter's mis-routing refusal | **ROUND 4: MEASURED, THEN CLOSED.** Round 3 left it at source level; the transposition is **0 bytes**, `arbiter.py` `fdb4ed0520eeb721` → `9111f627ef639ecc`, and it was **21/21 green**. Now red in `test_arbiter.py` on 2 checks. Round 3's reasoning was right: `test_arbiter.py:452` says it *"names the source and the actuator it does not belong on"* and then asserts `"peak" in r_mis.scope_errors[0]`. Under the swap the sentence becomes `"inverter-b: a SITE claim filed on unit 'peak'"` — and `"peak" in …` is **still true**. A claim wider than its assertion, which is habit 14's own shape. |
+| **B13** | `validate.py:723` | `meter_phases` / `meter_max_age_s` | the startup refusal | **NO** for the ordered pair. |
+| **B14** | `validate.py:1211` | `arbitrage_soc_floor` / `arbitrage_soc_ceiling` | the startup refusal | **NO** for the ordered pair. |
+| **B15** | `watchdog.py:667` | `cfg.min_w` / `cfg.hold_s` | the `SIGN_DISAGREEMENT` sentence's `(limits: both over 300 W, held over 180 s)` clause | **YES**, and it is worth naming because it shows the habit works. `test_watchdog.py`'s SAFETY-30 section asserts the site instance's **whole sentence with `==` against a literal**, the `(limits: …)` clause included. Full-string equality is habit 14 taken to its limit. |
+| B16 | `main.py:237` | `i.name` / `i.max_w` | the roster log line | **not real** — a `str` beside a `:.0f` format. The same over-report as A5–A6: a mixed-type transposition raises rather than lying. |
+| **B17** | `arbitrage.py:377` | `v.spread_eur_kwh` / `v.required_spread_eur_kwh` | the DISCHARGE decision's `reason` | **ROUND 4, NEW, and MEASURED: 0 bytes, 21/21 green.** Not visible to round 3 at all — the sentence is handed to a constructor as `reason=`, and the sink walker scored only *assignments*. The row then reads *"0.0400 above the cheapest and clear of the 0.1200 this cycle had to cover"* with the two swapped: a trade justified by a spread it did not clear. |
+| **B18** | `arbitrage.py:393` | same pair, CHARGE branch | the CHARGE decision's `reason` | **ROUND 4, NEW, MEASURED: 0 bytes, 21/21 green.** |
+| **B19** | `main.py:2652` | `g.reason` / `g.soc_floor_reason` | the `goodwe_peak_soc_floor` notification body | **ROUND 4, NEW, MEASURED: 0 bytes, 21/21 green.** The alarm then opens with the *reason the floor bound* and closes with the *guard's own conclusion*, i.e. both halves of a two-part explanation in the wrong order, in the one message SAFETY-24/25 exist to send. |
+| B20–B22 | `main.py:2558`, `main.py:2652` (two more pairs) | `g.reason` / `g.ceiling_w`, `g.ceiling_w` / `g.soc_floor_reason` | the same two notifications | **new in round 4, NOT measured** — mixed types (`str` beside `:.0f`), the same over-report class as B16. |
+
+**⚠️ Six of these twenty-two were invisible to round 3, and the reason is one
+line of the sink classifier.** It scored a sentence a MESSAGE when it was
+appended, logged, raised, or assigned to a `reason`-shaped **name**. This
+codebase mostly builds operator sentences as `Decision(…, reason=f"…")` and
+`out.append({"text": f"…"})` — a **keyword argument** and a **dict key**, which
+that walker stepped straight past. Both are message sinks now.
+
+### 7d. What this enumeration does NOT close, with sizes
+
+* **A3 is a measured, open survivor.** `dev_min`/`dev_max` transposed in
+  `rail_unreachable()`'s NOT COVERED row: **0 bytes, 21/21 green.** It is
+  disclosed here rather than fixed, because closing it wants a `test_freeze.py`
+  or status-page fixture with a device whose two bounds are **asymmetric** —
+  every fixture in the repository uses `±d` — and that is a different file's
+  card. It is a **status-page row**, not a latching alarm.
+* **B1 is a second measured, open survivor.** `inv.dev_min` and `inv.dev_max`
+  transposed in `main.py:3231`'s status row: **0 bytes**, fingerprint
+  `61aa413f…` → `ac36a97b…`, **21/21 green**. The page then tells the operator
+  the device accepts `130…−120 W`. Same disposition as A3: **A3 is the row the
+  freeze detector prints when the rail is UNREACHABLE, B1 the clause the ARMED
+  row prints when the device is what set the rail** — the two rows in which that
+  detector ever names a device range, and neither one's operand order is
+  asserted anywhere.
+* **Thirteen further census-B sites are unpinned and UNMEASURED.** B2–B14 above
+  are determined at the **source level** — the distinguishing literal appears in
+  no `test_*.py`, or the check that exists asserts a substring wider than its
+  own claim — and were **not** mutated. That is a weaker statement than A1–A4
+  and B1, and is written down as one.
+* **B12 is a check whose CLAIM is wider than its ASSERTION**, which is habit
+  14's own shape one module over. `test_arbiter.py:452` says
+  `scope_violations` *"names the source and the actuator it does not belong
+  on"* and then asserts `"peak" in r_mis.scope_errors[0]`. Swap `c.source` and
+  `c.actuator` in `arbiter.py:264` and the sentence becomes
+  *"inverter-b: a SITE claim filed on unit 'peak'"* — and the substring is still
+  found. Source-level, not mutated, and not fixed here.
+* **B6 is the closest thing to a repeat.** SAFETY-31's `circ_reason` is
+  persisted and re-read after a restart, exactly like `sign_reason`, and its
+  two limits are graded by a bare `"CIRCULATING_POWER" in reason`. This card
+  does not fix it; §6a already declines to touch `circ_wd`, and this is the
+  precise shape of what that declining costs.
+* **The instrument's own blind spots** are printed by the instrument, every
+  run: semantic symmetry it cannot spell (it under-reports), census B pairs
+  that are the same *kind* but not the same *shape*, `%s`-style logging and
+  non-f-string payloads, anything outside `app/`, and the one way it
+  **over-reports** — it erases the sentence, so a swap that would make the
+  formatting itself raise is scored as changing no decision (A5–A6 above).
+
+### 7e. Census C — the sentence an object returns about itself (round 4)
+
+**Why there is a third census.** A and B between them covered **one syntactic
+sink**. Everything either of them reported was a sentence that is appended,
+assigned, or logged; **none was returned**. Census A's RETURN bucket only ever
+held a callee formatting its own **parameters**, so a method formatting its own
+**attributes** and handing the string back fell between them — and that is the
+whole `describe()` / `explain()` / reason-builder family, which is where the
+operator sentences in this codebase actually live.
+
+**The test** is census B's — one f-string, two interpolations **one leaf apart**
+— run over the RETURN sink, plus one thing B never needed: **a returned string
+is not yet a message.** `store.unit_key()` and `mqtt.unit_state_key()` return
+f-strings too, and swapping there renames a store key and an MQTT topic, which
+every ordinary check can see (MAINT-05). So the sink of a returned sentence is
+**resolved through its call sites**: it is in this family only when some caller
+in `app/` hands it to an operator. That resolution matches on the **bare method
+name**, which over-collects — at least four unrelated classes have an
+`explain()` — so every verdict is printed **with the sites that produced it**,
+and a MESSAGE verdict is a prompt to read them, not a proof.
+
+The scan reports **53 returned pairs, 39 reaching an operator, 16 of those
+sharing a format spec** (two values rendered alike, so a transposition is silent
+rather than visibly broken). It **rediscovered both members this round was sent
+to fix without being told where to look**, which is the only reason to trust the
+rest of the list.
+
+| # | site | pair | reaches an operator as | Δ bytes | verdict |
+|---|---|---|---|---|---|
+| **C6** | `clamp.py:253` `ClampResult.describe()` | `requested_w` / `applied_w` | §15 action log (`main.py:1366`) **and** the ClampWatchdog notification reason (`main.py:2452`) | **0** | **was a SURVIVOR at 21/21 — now RED**, `test_clamp.py` part 6d, 4 checks |
+| **C7** | `peakguard.py:493` `PeakDecision.explain()` | `projected_w` / `ceiling_w` | status row `main.py:3313`; action log `main.py:1951` on the release edge | **0** | **was a SURVIVOR at 21/21 — now RED**, `test_peakguard.py` part 13, 3 checks |
+| C1 | `allocator.py:154` `UnitPlan.explain()` | `self.span` / `self.why` | the arbiter/allocator log line | **0** | **SURVIVOR, 21/21 green** |
+| C2 | `allocator.py:160` | `self.span` / `self.why` | the ENVELOPE VIOLATED line | **0** | **SURVIVOR, 21/21 green** |
+| C3 | `allocator.py:162` | `self.span` / `self.why` | the ordinary in-envelope line | **0** | **RED** — `test_alloc.py` already asserts that whole literal. The one member of this census the suite could already see, and it says the habit works. |
+| C4a | `arbiter.py:344` `UnitBounds.explain()` | `self.lo` / `self.hi` | `CONTRADICTION within the unit (device lo=… > peak hi=…)` | **0** | **SURVIVOR, 21/21 green** |
+| C4b | `arbiter.py:344` | `self.lo_src` / `self.hi_src` | the same sentence, the two SOURCE names | **0** | **SURVIVOR, 21/21 green** |
+| C5 | `arbiter.py:392` `Resolution.explain()` | `self.winner` / `self.bound_by` | `main.py:2236`'s `ARBITER:` action-log row and `self.reason` at `main.py:2329` | **0** | **SURVIVOR, 21/21 green** — the winner and the limiter swap names, on the line §10.1 exists to make legible |
+| C8 | `tariff.py:279` `PeakReading.explain()` | `self.month` / `self.detail` | the PEAK UNREADABLE row | **0** | **SURVIVOR, 21/21 green** |
+| C9 | `tariff.py:528` `Projection.explain()` | `self.projected_w` / `self.elapsed_s` | the projection line | **0** | **SURVIVOR, 21/21 green** — watts printed as seconds and seconds as watts, both `:.0f` |
+
+**Not in the family, and the scan says why rather than dropping them silently:**
+`inverter.py:338` `__repr__()` and `static_tariff.py:378` `words` are reported
+**UNRESOLVED — no call site inside `app/`** (a `__repr__` is called by the
+interpreter, not by a name the scan can match); `price_forecast.py:421/428` and
+`tariff.py:214` `month_key()` resolve to **OTHER** — `month_key` is a **store
+key**, which is MAINT-05's case and a swap there is behaviour every check sees.
+
+### 7f. Round 4's mutation ledger
+
+Same protocol as §4: a fresh full-repo copy per mutation, `:ro`, bytecode
+purged **and the purge count printed** before the edit, the edited file
+**re-read from disk**, both sides' length and sha256 printed, and the full
+**21-file** suite via `tools/mutation_run.sh`. Every row is a pure
+transposition, so **every Δ is 0 bytes** — verified, not assumed: `len(old) ==
+len(new)` is asserted before the write and `len(after) == len(before)` after it.
+
+**⚠️ And every row was also required to change the ANSWER.** A byte delta says
+the file moved; it does not say the sentence did. Each mutated tree is rendered
+through a scratch probe that evaluates the shipped f-string with **distinct
+operands** and diffs it against the same render of the clean tree. **The first
+cut of that probe numbered the operands by ORDER OF APPEARANCE** — so after a
+transposition the other leaf took the same number and all thirteen diffs came
+back **empty**, which reads exactly like "the edit is inert". Keying the value
+to the **name** fixed it. That is the same defect as everything else in this
+card, in the instrument this time: a measurement comparing the swap against
+itself.
+
+| mutation | file, before → after (sha256, 16) | Δ | verdict |
+|---|---|---|---|
+| C1 `allocator.py:154` span↔why | `10c1b26ed0099654` → `ac0c174de1ec28ad` | 0 | **SURVIVED 21/21** |
+| C2 `allocator.py:160` span↔why | `10c1b26ed0099654` → `9b10730f4659befd` | 0 | **SURVIVED 21/21** |
+| C3 `allocator.py:162` span↔why | `10c1b26ed0099654` → `07097bf5da31f0c6` | 0 | **RED** — `test_alloc.py` |
+| C4a `arbiter.py:344` lo↔hi | `fdb4ed0520eeb721` → `009820de7ef0eff0` | 0 | **SURVIVED 21/21** |
+| C4b `arbiter.py:344` lo_src↔hi_src | `fdb4ed0520eeb721` → `04cb8cf69dfc7432` | 0 | **SURVIVED 21/21** |
+| C5 `arbiter.py:392` winner↔bound_by | `fdb4ed0520eeb721` → `9238c3db920da8ad` | 0 | **SURVIVED 21/21** |
+| **C6** `clamp.py:253` requested↔applied | `0153133741497fa5` → `47e4e371043e3201` | 0 | **SURVIVED 21/21 before — RED after**, `test_clamp.py`, 4 checks |
+| **C7** `peakguard.py:493` projected↔ceiling | `d95df61a51716c26` → `2d2ee3d0bcd51251` | 0 | **SURVIVED 21/21 before — RED after**, `test_peakguard.py`, 3 checks |
+| C8 `tariff.py:279` month↔detail | `82790523dd5227c9` → `4b2147ca17a28425` | 0 | **SURVIVED 21/21** |
+| C9 `tariff.py:528` projected↔elapsed | `82790523dd5227c9` → `517e9148d26a243a` | 0 | **SURVIVED 21/21** |
+| B17 `arbitrage.py:377` spread↔required | `67fbf949b2938349` → `cddd8045bdeb5e29` | 0 | **SURVIVED 21/21** |
+| B18 `arbitrage.py:393` spread↔required | `67fbf949b2938349` → `04a4f3ad3d255de1` | 0 | **SURVIVED 21/21** |
+| B19 `main.py:2652` reason↔soc_floor_reason | `61aa413fb890433e` → `bbcbb28f476a98d0` | 0 | **SURVIVED 21/21** |
+| **B12** `arbiter.py:264` source↔actuator | `fdb4ed0520eeb721` → `9111f627ef639ecc` | 0 | **SURVIVED 21/21 before — RED after**, `test_arbiter.py`, 2 checks |
+
+**14 measured, 12 survived the full suite before this round's checks, 1 was
+already caught, 3 are caught now.** The tree these were taken on is
+`SAFETY-38` @ `357cb4f` rebased on `release/1.0` @ `9e42cec`; `app/main.py` is
+234 542 bytes.
+
+### 7g. What round 4 does NOT close, with sizes
+
+* **Eleven measured zero-byte survivors are left open** — C1, C2, C4a, C4b, C5,
+  C8, C9, B17, B18, B19 and the three already open from round 3 (A3, B1, and the
+  B2–B11/B13–B14 source-level set). Each is a sentence an operator reads and
+  none is a control decision. They are disclosed with their measurement rather
+  than pinned because pinning each one wants a fixture in the file that owns the
+  module — `test_alloc.py`, `test_arbiter.py`, `test_tariff.py`,
+  `test_arbitrage.py` — and this card has now spent four rounds inside
+  `test_watchdog.py`'s subject. **An enumerated list with honest gaps beats a
+  fifth round finding a fifth instance**; what would NOT be honest is a fifth
+  round finding one that is **not on this list**.
+* **`main.py:1951`, the action-log surface of the peak-guard idle line,** is
+  unpinned. The status row off the same `explain()` is pinned; the second call
+  site is not, and §4c is the card about exactly that costing a round.
+* **The largest remaining hole is not in any census: `%s`-style lazy logging.**
+  `_LOG.error("… %s … %s", a, b)` puts the two operands in *arguments*, not in
+  an f-string, so nothing here looks at them and the transposition is the same
+  zero-byte edit. The tool now says so first in its NOT-SCANNED list, **with
+  the size measured rather than asserted: 31 such calls across 8 modules in
+  `app/`, each one listed**.
+* **The tool's own blind-spot list was the round-4 blocker and is now two
+  lists.** "What this scans, and what it does not" enumerates its message sinks
+  from the constants themselves and then names, in order, what it never looks at:
+  `%s`-style logging, `.format()`/`%`/`+`/`.join()` sentences, a sentence that
+  leaves through a dict or dataclass and is rendered elsewhere, `yield`ed
+  sentences, attributes outside the `reason`-shaped set, and everything outside
+  `app/`. "What it can see but gets wrong" keeps the five gaps round 3 printed,
+  with the over-report gap now backed by a **printed format-spec column** so a
+  reader can tell a silent same-typed transposition from a noisy mixed-type one.

goodwe_controller/DECISIONS/SAFETY-39-slew-against-the-rail.md

@@ -0,0 +1,438 @@
+# SAFETY-39 — `slew_w` is a ratio to the rail, and `gain` is the constant that is still wrong
+
+**Status:** decided and implemented on branch `SAFETY-39`.
+**Card:** SAFETY-39 — *"`slew_w` was derived at a 1500 W clamp and runs at 5000,
+so the loop outruns the plant"*.
+**Nothing here reached the inverter.** The live install still runs the interim
+`slew_w: 400` applied by hand on 2026-09-05 12:00, which this branch's new rule
+accepts unchanged.
+
+---
+
+## 0. The three things a reader should take away
+
+1. **The overshoot is reproduced in simulation, and one half of it is not
+   reproducible at all.** The setpoint stepping to the rail and the meter
+   crossing from export into import are both reproduced, on two independent
+   plant models. The **−5154 W battery figure is not reproducible in either**,
+   because both clamp the plant at its rating. An acceptance criterion written
+   on it would pass on the broken configuration too, so none is. §2.
+2. **The deliverable is the relationship, not the number.** `slew_w: 0` now
+   means *follow the rail* and resolves to `SLEW_RAIL_FRAC * max_w`;
+   `validate.py` rule 10 refuses an explicit value faster than that against the
+   **site** rail. Verified by breaking it. §4, §5.
+3. ⚠️ **`slew_w` does not own the over-absorption. `gain` does, and `gain` was
+   not changed.** Re-deriving the slew removes the ≥ 900 W step — the symptom
+   that escalated 2 → 1 → 13 → 43 per 30 min on the morning of the excursion —
+   and removes nothing else. Anyone reading this card as "the overshoot is
+   fixed" is reading more than was delivered. §6.
+
+---
+
+## 1. The defect, stated in the terms the code uses
+
+`slew_w: 1000` was derived on 2026-08-22 against a **clamp of 1500 W**
+(goodwe/`NOTES.md`, *"Simulated 2 kW load step (gain 0.6, clamp 1500)"*). Its
+stated justification:
+
+> `slew: 1000` is the default because it puts most of the correction in the first
+> cycle **while still capping how far the loop can jump ahead of the inverter**.
+
+At 1500 W that sentence is true, and the reason is the rail rather than the
+number: 1000 W/cycle reaches the rail in two cycles, so the excursion is bounded
+by 1500 W whatever the loop does.
+
+The live install then went to `max_w: 5000` and the constant did not move.
+`DRIVER-07` ("raise actuator power cap to full inverter rating") is still in To
+Do; the cap was raised ahead of it and `slew_w` was never revisited. **Nothing
+in the code is broken.** The rail moved and the derivation did not.
+
+| | derived at | shipped default | live install |
+|---|---|---|---|
+| `max_w` | **1500** | 2000 | **5000** |
+| `slew_w` | 1000 | 1000 | **1000** |
+
+Measured on the owner's system, 2026-09-05 11:43–11:46:
+
+```
+11:43:55  grid  -3385 W                        a real 3.4 kW export
+11:43:56  SP    380 → 1380 → 2380 → 3380 → 4380 → 5000     +1000 per 2 s tick
+11:44:47  batt  -5154 W                        ABOVE the 5000 VA rating
+11:45:55  grid  +2831 W                        flipped to 2.8 kW IMPORT
+          SP    5000 → 2930 → 3840 → 3750      hunting
+```
+
+Large (≥ 900 W) setpoint steps per ~30 min that morning: `2 → 1 → 13 → 43`.
+
+---
+
+## 2. ⭐ Reproduced first — and what could not be
+
+`tools/slew_sim.py --repro`, against admin/goodwe's `plantsim.Plant`, the real
+`compute()`, and the firmware's own encoder on the wire. Gain 0.6, `max_w` 5000,
+`slew_w` 1000, 2 s tick, one 3385 W export step at t = 10 s:
+
+```
+    t   grid in  setpoint   battery  grid out  reason
+   10     -3739      -280       290     -3675  slew-limited
+   12     -3675     -1280        57     -3442  slew-limited
+   14     -3442     -2280      -316     -3069  slew-limited
+   ...
+   34     -1012     -5000     -2823      -562  i-clamped      ← the rail
+   38      -167     -5000     -3541       156  saturated-freeze  ← EXPORT → IMPORT
+   44       562     -4310     -4018       633  saturated-freeze
+   50       544     -3210     -3804       419  tracking
+```
+
+Reproduced: the setpoint stepping a full 1000 W per tick to the rail, the loop
+absorbing ~640 W more than the site needed, and the meter crossing from **3.7 kW
+of export to +633 W of import** — the loop manufacturing the error it then
+chases. Over a family of 51 export steps (1.0–4.2 kW × 3 phases), **48 of 51**
+runs contain a ≥ 900 W setpoint step.
+
+### ⚠️ What is NOT reproducible, and why no criterion is written on it
+
+`plantsim.Plant.limit()` clamps the plant at `p_max`. The modelled battery
+**cannot exceed its rating by one watt, at any tuning, on any step, ever.**
+Neither can `test_control.py`'s independent model. So:
+
+* the **−5154 W excursion is not reproducible in simulation at all**, and this
+  is a property of the models rather than of the tuning;
+* the card's AC *"battery power no longer exceeds `max_w` on a step of the size
+  observed"* is **unfalsifiable in simulation** — it passes identically on the
+  configuration that produced the excursion. It is the one acceptance criterion
+  this card had to **rewrite rather than meet**, per the board's own rule that a
+  third review round means the AC is wrong.
+
+What replaced it, and what is graded in CI: **the ≥ 900 W step is gone from
+every member of the family**, and **the meter excursion and the over-absorption
+are measured and reported rather than claimed to be fixed.**
+
+### The two models agree
+
+`test_control.py`'s in-repo first-order lag and admin/goodwe's ramp-plus-lag
+`plantsim.Plant` are independent, and they agree on every sign and rank:
+
+| | in-repo model | `plantsim.Plant` |
+|---|---|---|
+| ≥ 900 W steps at `slew_w` 1000 | 48/51 | 48/51 |
+| ≥ 900 W steps at the derived value | 0/51 | 0/51 |
+| over-absorption, slew 1000 → 250 | 1005 → 1330 W | 958 → 1081 W |
+| over-absorption, gain 0.6 → 0.2 | 1109 → 393 W | 987 → 435 W |
+
+---
+
+## 3. The derivation
+
+The constraint, in words, and it is the 2026-08-22 sentence made checkable:
+
+> **The loop must not traverse its full output range faster than the plant takes
+> to settle.**
+
+Three measured quantities, and each is named where it came from:
+
+| | value | where it was measured |
+|---|---|---|
+| plant settling time | **18 s** | goodwe/`NOTES.md` §5.10, 2026-08-22 — a 1.78 kW kettle step driven from HA off a plug that meters its own draw. ~18 s up to the deadband, ~23 s down. **18 is taken because it is the shorter and therefore the looser bound**; this is a refusal boundary, and rules 5 and 6 refuse the impossible case only, never "close to the rail". |
+| control tick | **2 s** | the live install, measured 2026-09-05 — the setpoint stepped +1000 W every 2 s. `run_control()` runs a cycle on a changed meter value or on `cycle_floor_s`, whichever comes first, so the tick is the *meter's* rate. |
+| output range | `max_w` | `main.py` builds `Tuning(max_w=self.site_max_w)`, the **roster sum**. |
+
+```
+SLEW_RAIL_FRAC = LOOP_TICK_S / PLANT_SETTLE_S = 2 s / 18 s = 0.1111   (9 ticks)
+
+slew_w  ≤  SLEW_RAIL_FRAC × max_w
+```
+
+| rail | derived `slew_w` | ticks to cross | seconds to cross |
+|---|---|---|---|
+| 1500 (where the original was derived) | 167 W | 9 | 18 s |
+| 2000 (shipped default) | 222 W | 9 | 18 s |
+| **5000 (the live install)** | **556 W** | 9 | 18 s |
+| 9600 (with inverter B — **datasheet, not measured**) | 1067 W | 9 | 18 s |
+
+And the configuration that was measured failing: `slew_w` 1000 at `max_w` 5000
+crosses the rail in **5.0 ticks = 10 s**, against a plant that takes 18 s.
+
+### ⚠️ The tick is the weak term and it is not wrong in the safe direction
+
+A **slower** meter makes this bound conservative — it refuses configurations that
+would have been fine, which is visible immediately and costs one edit. A meter
+**faster** than 2 s makes it loose by exactly that ratio and nothing in this
+add-on would say so. `run_control()`'s `await asyncio.sleep(1)` bounds the tick
+below at 1 s, so the worst case is a factor of two — but if a faster meter is
+ever fitted, `LOOP_TICK_S` has to be **re-derived, not merely re-read**. Compare
+`validate.FIRMWARE_INGEST_VETO_S`, which carries the same kind of copy and can
+only ever be wrong the other way; that difference is why both numbers are
+written out in `control.py` rather than their quotient.
+
+### ⚠️ The rig cannot pick 556 out of the table, and is not asked to
+
+`tools/slew_sim.py --slew`, worst case over 51 export steps:
+
+```
+  slew_w 1000   ← 2026-09-05 live pair   step 1000 W   48/51 ≥900 W   over-absorbed  958 W
+  slew_w 800                             step  800 W    0/51 ≥900 W   over-absorbed 1107 W
+  slew_w 700                             step  700 W    0/51 ≥900 W   over-absorbed 1133 W
+  slew_w 600                             step  600 W    0/51 ≥900 W   over-absorbed 1058 W
+  slew_w 555    ← the derived value      step  560 W    0/51 ≥900 W   over-absorbed  987 W
+  slew_w 500                             step  500 W    0/51 ≥900 W   over-absorbed 1029 W
+  slew_w 400    ← the live interim       step  400 W    0/51 ≥900 W   over-absorbed 1150 W
+  slew_w 300                             step  300 W    0/51 ≥900 W   over-absorbed 1143 W
+  slew_w 250                             step  250 W    0/51 ≥900 W   over-absorbed 1081 W
+```
+
+The ≥ 900 W step disappears at 800 and stays gone. Below that the table is
+**flat and slightly non-monotone**, and 800 is *better* than 556 on
+over-absorption. So the rig does not choose the number — **the constraint
+chooses it, and the rig says what the constraint does and does not buy.** That
+is the same relationship the 2026-08-22 table had to its own three columns.
+
+⚠️ **A single step is not evidence here.** The deadband, the 10 W quantisation
+and the phase of the step against the tick move the result by hundreds of watts,
+non-monotonically. The first cut of this derivation was a single step and ranked
+gain 0.3 as *worse* than 0.6, which the family shows is backwards. Every number
+above is a worst case over a family, which is how admin/goodwe grades the same
+kind of quantity (`config.yaml`'s "1890 closed-loop runs", "924 runs").
+
+---
+
+## 4. What ships — the relationship, not the number
+
+**`slew_w: 0` means FOLLOW THE RAIL.** `control.slew_limit_w()` resolves it to
+`SLEW_RAIL_FRAC * max_w`. It is the shipped default and it is the only value
+that cannot be left behind when the rail moves. This is the idiom
+`integrator_max_w: 0` has carried in the same options block since it was added —
+not a new concept, the same one, applied to the key that needed it.
+
+An explicit number is still accepted **and is never silently reduced**: the live
+install runs 400, and silently reducing an operator's stated bound is case (a)
+in `validate.py`'s own docstring — the defect that whole module exists to
+prevent.
+
+**`validate.py` rule 10** refuses an explicit `slew_w` above
+`SLEW_RAIL_FRAC × site rail`. Graded against **`sum(unit_caps(opts))`**, the
+roster sum — the same number `Controller.site_max_w` builds — and *not* against
+the flat `max_w` and *not* against the weakest unit. Rules 5, 6 and 8 take
+`min()` because each grades one watchdog, one shaping claim, one pack. `slew_w`
+is not a per-unit quantity at all: `compute()` emits the **site** target and the
+allocator divides it afterwards.
+
+⚠️ `config.yaml`'s note on `site_sign_disagree_w` says there is deliberately no
+rule pairing a site quantity with `max_w`, "because … `validate_startup_config()`
+is handed options rather than a roster". That objection is to grading a site
+quantity against the **flat key**, and it is answered rather than ignored:
+`unit_caps()` already reads the roster the add-on will build, so the roster sum
+*is* available at startup, and `site_rail_w()` is that number.
+
+---
+
+## 5. ⭐ Verified by breaking it
+
+`test_validate.py`, section 10 — the acceptance criterion written as a test:
+
+```
+    restoring slew_w 1000 at max_w 5000 -> 1 problem(s)
+      slew_w is 1000 W against a site rail of 5000 W, so the loop crosses its
+      whole output range in 5.0 cycles - 10 s at the 2 s tick this site was
+      measured running - while the plant takes 18 s to settle …
+```
+
+and the four things the refusal has to say, each graded separately: which rail
+it used, how long the crossing takes, which measurement it is graded against,
+and what to do about it (including `0`, which cannot go stale). Plus:
+
+* **equality starts** — at exactly the derived value the crossing takes exactly
+  the settling time, which is the constraint met, not violated (rule 6's case,
+  not rule 5's; getting it backwards would refuse the recommended value);
+* **one watt of slack starts** — a boundary that is not meaningful to one watt
+  must not refuse on one watt;
+* **the live interim `slew_w: 400` starts**, and so does the schema floor —
+  there is no such thing as too slow here, and refusing it would refuse the
+  mitigation that is holding;
+* **`slew_w: 0` starts at every rating from 100 W to 15 kW.**
+
+`test_control.py` grades the same boundary from the law's side, so the rule can
+only ever refuse what the ratio says is too fast, and the two cannot drift apart.
+
+---
+
+## 5b. What the change found in this repository's own tests
+
+Five files moved, and **none of them moved because a number was rounded
+differently**. Each is worth reading as a finding.
+
+**Two fixtures encoded the defect.** `test_inverter.py`'s `BASE_OPTS` paired
+`slew_w: 1000` with `max_w: 5000` — the 2026-09-05 configuration exactly — and
+`test_loop.py`'s `BASE` paired 1000 with 2000. Both were typed when those rails
+were new; nothing in either file had noticed. Rule 10 refused them on its first
+run, so those fixtures **would not start**. That is what a rule about a
+*relationship* is for, and it is the clearest evidence the rule is not a
+formality.
+
+**Two reproductions depended on a default they never named.**
+`test_alloc.py`'s `close_loop` and `test_freeze.py`'s "make both terms
+reachable" case reached `slew_w: 1000` through `Tuning`'s default. ARCH-01's
+4000 W broadcast limit cycle and SAFETY-18's proof-of-capability alarm would
+both have gone quiet — reporting a measured finding as *absent* because a
+default moved underneath them. Both now write the number beside the measurement
+it belongs to.
+
+**One harness had a latent off-by-one that only a ramping loop could expose.**
+`test_watchdog.py` graded SAFETY-02's banner by pairing `c.grid` with
+`last_write` sampled **after** `cycle()`, while the detector is evaluated
+**inside** `cycle()` against the *standing* command from the previous one. At
+`slew_w: 1000` the loop reached its rail in two cycles and consecutive commands
+were identical, so the wrong pair and the right pair were the same numbers. At a
+rail-following slew they differ by one step and the check went red. `_drive()`
+now has a `pre` hook that reads the operands the detector will actually use, and
+the check reads the **latching** cycle rather than the one before it. The
+assertion is strictly stronger than it was.
+
+**One tripwire had two assertions that were exact by coincidence.**
+`test_peakguard.py` part 10c read `limited_discharging == limited` (49/49) and
+`min_soc <= bms_soc_floor + 0.05`. At the slower slew the loop drains that pack
+~82 Wh less over the same two hours and no longer touches the cut-out *inside
+that window*: 48/49, low-water 10.57 % against a 10 % cut-out, 0 cycles at the
+BMS limit instead of 190. **The finding is unchanged and is sharper on the
+measure that carries it** — 162 cycles of granted discharge below the EMS floor,
+up from 138. The two exact equalities were artefacts of one tuning, the old and
+new numbers are tabulated in the file beside the checks, and the assertions now
+grade the substance. ⚠️ *Loosening an assertion to get a branch green is the
+first thing a reviewer should suspect here; the table is there so the suspicion
+can be settled rather than argued.*
+
+---
+
+## 6. ⚠️ `gain: 0.6` — measured, and deliberately NOT changed
+
+The card asks whether `gain` still holds at this clamp. **It does not, and here
+is the measurement.**
+
+`tools/slew_sim.py --gain`, `slew_w` at the derived 556 W, same 51-step family:
+
+```
+  gain 0.6  ← shipped     over-absorbed 987 W   meter driven to +987 W
+  gain 0.5                over-absorbed 941 W
+  gain 0.4                over-absorbed 977 W
+  gain 0.3                over-absorbed 876 W
+  gain 0.2                over-absorbed 435 W
+  gain 0.1                over-absorbed  66 W
+```
+
+Against the slew column in §3, which is flat. The mechanism is visible in
+`control.py` and is structural rather than empirical:
+
+* **`slew_w` bounds the OUTPUT.**
+* **The integrator accumulates `gain × error` per cycle** and is bounded only by
+  `integrator_max_w`. At gain 0.6 into a 3.4 kW error it moves **~2040 W per
+  tick** and reaches a 5000 W rail in **under three ticks, whatever `slew_w`
+  is**.
+
+So the 2026-08-22 derivation's own sentence — *"the gain, not the slew, is the
+limit by then"* — has become literally true, and `gain` is the term that owns
+the over-absorption at this rail. It is written about a 1500 W rail, where
+`gain × 1500 = 900 W` and the clamp caught it in two cycles; at 5000 there is
+3.3× more room to wind before the clamp binds.
+
+**Why nothing was changed:**
+
+* `gain` is a live control-law constant on a running house. Two of them moving
+  in one release makes the next measurement uninterpretable — and the interim
+  `slew_w: 400` has been in service since 2026-09-05 12:00, so there is a clean
+  baseline to measure the next change against and it would be destroyed.
+* A validator rule pairing `gain` with a rail would be **inventing a
+  relationship nobody has measured.** The bound would have to be
+  `gain × error_max ≤ SLEW_RAIL_FRAC × max_w`, and `error_max` is the
+  disturbance, which is not config and is not bounded.
+* `integrator_max_w` is **not** the lever it looks like: it bounds the output as
+  well as the accumulator (`target = clamp(i_w, ±max_w)`), which is why setting
+  it to 2000 on the live system on 2026-09-05 capped the inverter to 2000 W of
+  its 5000 and was reverted the same day.
+
+This is named in `validate.py`'s *"deliberately not refused"* list so that it is
+a known open item rather than an omission, and it is asserted in
+`test_control.py` so that nobody can quietly read this card as having fixed it.
+**It wants its own ticket.**
+
+---
+
+## 7. N = 1 → N = 2: the rail is what moved
+
+⚠️ **Inverter B does not exist on site** (SPIKE-04, ≈ 2026-09-12). Its figures
+are from its **datasheet and serial**, not a measurement: GW5048D-ES, serial
+`55048ESU22AW0992`, 4600 W, pack 4 × Dyness DL5.0C = 20.48 kWh, floor 10 %
+(goodwe/`NOTES.md` §1.1b) — and the 4600 W is printed under *battery input data*,
+so it may be DC, in which case the AC ceiling is nearer 4324 W.
+
+⚠️ **And `sim/plantsim.py`'s `INVERTER_B` is inverter A copied**, carrying
+`measured=False`. **Every two-inverter row below is a result about two copies of
+A on a 10000 W rail, not about the ~9600 W site B implies.**
+
+**The site rail becomes `sum(max_w)` ≈ 9600 W while `slew_w` is per-site.** The
+derived value there is `0.1111 × 9600 = 1067 W` per tick, which at an even split
+is 533 W per unit against each unit's own 5000/4600 W rating — ARCH-01's
+split-invariance holding, as its `two_master_gain_sweep` already shows.
+
+**Does the enforced relationship produce it automatically? Yes.** Rule 10 reads
+`sum(unit_caps(opts))` and `slew_limit_w()` reads `Tuning.max_w`, which
+`main.py` sets from `Controller.site_max_w`. Declaring inverter B moves both,
+with no operator action and no second derivation. That is the property that
+makes this a fix rather than a re-tune, and `test_validate.py` asserts the
+9600 W arithmetic directly.
+
+⚠️ **But the direction of the rule is not the one the ticket assumed, and it
+must be said.** A rail that **grows loosens** this bound: `slew_w: 1000`
+crosses 9600 W in 19.2 s and **passes**, while the same 1000 at 5000 W is the
+configuration measured failing. That is what the constraint says and it is
+correct — the bound is on how long the crossing *takes*. What the rule protects
+against is the constant being left behind when the rail moves, in either
+direction. **It is not a bound on how much power the site may command** (that is
+each unit's own `max_w` through the arbiter's `supervised` claim) **and it does
+not bound the over-absorption** (§6).
+
+⚠️ **The ≥ 900 W symptom goes stale at N = 2 the same way the constant did.**
+On the two-copies-of-A rows, 48/51 runs contain a ≥ 900 W step *at the derived
+value*, because at a 10000 W rail the derived step **is** 1111 W. A check
+written on the absolute 900 W would report the correct tuning as broken.
+Anything grading this symptom at N ≥ 2 has to grade it as a **fraction of the
+rail** too — which is this whole card, one layer out.
+
+---
+
+## 8. `max_w: 5000` — a recommendation, not a change
+
+The battery reached **5154 W against a 5000 VA inverter**, so the configured cap
+left no headroom for the overshoot that the loop was going to produce anyway.
+Three things are worth writing down and none of them is changed here:
+
+1. **The cap is the rating, so the overshoot has nowhere to go but past it.**
+   `compute()` bounds the *command* to `±max_w`; nothing bounds the plant's
+   response to a command at the rail, and §6 shows the loop asks for the rail on
+   any large step at gain 0.6. Recommend **`max_w` at 4500–4750 W**, i.e. 90–95 %
+   of the 5000 VA nameplate, leaving 250–500 W for the overshoot the loop still
+   has. This is `freeze.py`'s `RAIL_FRAC` argument applied to the cap itself.
+2. **The −5154 W may not be an AC figure at all.** `batt_entity` is the pack
+   sensor and `max_w` is graded against `0x0518`, the inverter's **AC** power —
+   `config.yaml`'s roster comment already records exactly this ambiguity for
+   inverter B. If the battery reading is DC, 5154 W DC is ~4900 W AC and the
+   inverter was never over its nameplate. **Nobody has measured which**, and the
+   recommendation above is worth making either way.
+3. **It is the owner's number.** `translations/en.yaml` marks `max_w` "THIS IS
+   YOUR NUMBER" precisely so it is not confused with a derived constant, and
+   changing it unilaterally in a pull request would undo that distinction.
+   `SAFETY-20`'s `min(max_w, dev_max)` settles the device side once ESPHome has
+   answered; the *headroom* question is a policy choice and belongs to the owner.
+
+---
+
+## 9. What was deliberately not done
+
+* **`saturation_w` and the deadband were not touched.** The card forbids it and
+  it is right to: widening either hides the symptom. The loop is following its
+  command correctly; the command is wrong.
+* **`gain` was not changed.** §6.
+* **`max_w` was not changed.** §8.
+* **`control.py`'s slew *limit* was not clamped to the bound.** An explicit
+  value above it is refused at startup, not quietly reduced — silently reducing
+  an operator's stated bound is case (a) in `validate.py`'s docstring.
+* **Nothing in admin/goodwe was modified**, and nothing reached the inverter.

goodwe_controller/DECISIONS/TEL-07-second-mqtt-device.md

@@ -0,0 +1,115 @@
+# TEL-07 — why inverter A does not get a device of its own, and B does
+
+**Status: DECIDED 2026-09-05.** MQTT discovery announces **two** devices at a
+roster of two: the existing one, unchanged, plus one for the second inverter.
+It does **not** announce one per inverter. This document exists because the
+symmetrical design is the obvious one, is tidier, and would destroy the live
+system's recorded history — so the next person to read `app/mqtt.py` needs the
+reason written down where they will find it before they "fix" it.
+
+Filed with TEL-07. Card `6a9bfa75f0a3550275ba4888`.
+
+---
+
+## 1. The mechanism, in one paragraph
+
+`app/mqtt.py`'s own note records the finding, tested on HA 2026.8: Home
+Assistant composes an entity id from the **device name plus the entity name**,
+and `object_id` in the discovery payload does **not** override it. So the device
+name is half of every entity id.
+
+The second half of the mechanism is the half that makes it silent. Home
+Assistant keeps the entity id it composed at **first** discovery. Re-scoping the
+device therefore does not rename an entity in place; it creates a **new** entity
+beside the old one. The recorded history stays on the old id, the old id stops
+updating, and nothing errors. Every dashboard card, template and automation that
+names it — including `goodwe_master_watchdog_held_*` and
+`goodwe_master_parked_at_0_w_*`, which are live — keeps pointing at a sensor
+that has quietly gone flat.
+
+`sensor.goodwe_p1_sample_age` is the sharp end of it: the ESP32's stale-input
+watchdog subscribes to that composed name, and its own comment calls this the
+failure that "FAILS SILENTLY AND LOOKS CORRECT".
+
+## 2. The two designs
+
+| | **one device per inverter** | **what shipped** |
+|---|---|---|
+| A's device | new: `inverter-a` | **the one it already has** |
+| B's device | new: `inverter-b` | new: `goodwe_rs485_controller_inverter_b` |
+| A's existing entity ids | **all renamed** | **byte-identical** |
+| A's recorded history | **stranded on dead ids** | kept |
+| watchdog automations | **silently broken** | untouched |
+| composed per-unit ids | `sensor.goodwe_inverter_a_*` / `..._b_*` | **the same** |
+| reads as | symmetrical and tidy | asymmetrical, and needs this file |
+
+The last two rows are the whole argument. The tidy design's only real benefit is
+a pair of symmetric, predictable entity ids — and the shipped design produces
+**exactly the same ids** by putting the unit's name in the *entity* name for the
+first roster entry and in the *device* name for the others. There is nothing
+left to buy, and the price was the live system's history.
+
+## 3. What is per-unit and what is site
+
+**Per-unit:** setpoint (this unit's share of the site target, the number its own
+heartbeat re-emits), battery power (`Inverter.batt`, register `0x0518`, this
+unit's own reading), SoC (`Inverter.soc` — **this** pack; the site row is the
+*emptiest* pack, which at N≥2 may be the other one), and the SAFETY-02 sign
+latch, which is one instance per actuator by construction.
+
+**Site:** `grid` and `p1_sample_age_s`. There is one P1 meter and one grid
+connection, so a per-inverter copy invents two of a thing there is one of — and
+`p1_sample_age_s` is a **watchdog input**, so a second copy is a second answer to
+"is the meter fresh?", one of which is always the one nobody is looking at.
+Circulating power is site because it *is* a property of the set
+(`sum(|Bᵢ|) − |sum(Bᵢ)|`); so are the controller status, the maintenance phase
+and the capacity-tariff peak.
+
+**Named as absent rather than left looking finished:** the card also lists
+"inverter AC power" and per-unit heartbeats as per-unit. Neither has a source in
+the add-on today — nothing reads an AC-power register per unit, and
+`Inverter.last_beat` is a monotonic loop clock with no wall-clock age published
+anywhere. Announcing them would create entities nothing ever feeds, which is the
+hazard the `omit` note in `mqtt.py` exists to refuse. They are gaps.
+
+## 4. Why a roster of one announces nothing
+
+Every install running today is a roster of one, and at N=1 the site rows **are**
+that unit's rows: `battery` is its power, `soc` is its pack. Four extra entities
+would be four new rows carrying numbers already on the dashboard, on a live
+system, for no information. `announced_units()` answers `[]` below
+`PER_UNIT_MIN_ROSTER`, and `Controller.publish()` reads **that same list** —
+the empty list is the gate on both halves, rather than a predicate written twice
+that could later disagree.
+
+## 5. How it was verified, and what that does not cover
+
+The claim is a **diff of the announced payloads** against `release/1.0`,
+generated by running that commit's module rather than transcribed from it:
+`9 topics, 0 missing, 0 changed, 0 added` at a roster of one, and
+`0 missing, 0 changed, 8 added` at a roster of two. `test_mqtt.py` part 2 shows
+`_announce()` publishes exactly what is diffed, so the comparison is against the
+bytes paho is handed.
+
+Sixteen mutations were run. Twelve are in the file as a running table, each
+named with the property it breaks. Three properties in that table exist only
+because the table found their absence — dropping the unit from the state topic,
+moving `grid` into the per-unit list, and `units=()` in main()'s publisher call
+were all green on the first run, as was a roster fallback that named two
+nameless entries `inverter-a`.
+
+**What it does not cover is listed in `test_mqtt.py` part 9, with sizes.** The
+largest item: Home Assistant itself is not in the loop. The entity-id
+composition is a **model**, anchored on exactly one measured id
+(`sensor.goodwe_p1_sample_age`, verified against the live system 2026-08-26).
+Closing that needs a broker, an HA and the owner present, and this card is not
+allowed near the live install.
+
+## 6. ⚠️ Inverter B does not exist
+
+Not until ~2026-09-12. Every roster of two in this repository's checks is
+**simulated**; B's `max_w: 4600` is the datasheet's figure for a GW5048D-ES
+(serial `55048ESU22AW0992`), recorded in `goodwe/NOTES.md` §1.1b, and nothing
+about B has ever been measured. No entity described here has been seen on a
+broker. When the second inverter is installed, the first thing to check is that
+the eight ids in §1 are still updating — not that the new ones appeared.

goodwe_controller/DOCS.md

@@ -40,6 +40,30 @@ hardware holds it there.
 
 ## Configuration
 
+### What the Configuration tab actually shows you (UX-01)
+
+Since **UX-01** the add-on ships `translations/en.yaml` and `translations/nl.yaml`,
+so Home Assistant's *Configuration* tab renders human labels and a description
+for every option instead of the raw option keys. What that does and does not buy
+you is worth stating plainly, because it was **measured against the Supervisor
+image this site runs** (`ghcr.io/home-assistant/amd64-hassio-supervisor:2026.08.0`)
+rather than assumed — `tools/supervisor_shape_probe.py` section F prints the
+whole rendered list, in both languages.
+
+| | |
+|---|---|
+| **All 70 options are always shown** | The frontend keeps a field when `name in options \|\| required`, and every key is in `options:`. There is no "advanced" fold |
+| **Order comes from `schema:`** | `App.schema_ui` is `UiOptions(...)(data["schema"])`, so the **schema half** of `config.yaml` decides the order the tab renders in — not the `options:` half |
+| **There are no section headers** | Add-on options are a flat list: no header primitive, no per-option advanced flag, no units on the input, no sliders. Grouping is approximated by **order** plus the `Group · ` prefix in each label, and by nothing else |
+| **Groups, in task order** | Hardware → Meter → Limits → Tariff → Maintenance → Safety → Advanced |
+| **The description says whether to touch it** | A number that was **derived** names the campaign it came from and says not to change it without re-deriving; a number that is genuinely yours (`max_w`, `peak_cap_w`) says **"THIS IS YOUR NUMBER"**; and `cycle_cost_threshold_eur`, which is neither, says it is an open product question |
+| **Dutch falls back per key** | `translations[your language]?.name \|\| translations["en"]?.name \|\| the raw key`. A key missing from `nl.yaml` degrades to English; a key present but wrong does not degrade at all |
+| **⚠️ The per-entry keys inside `inverters:` still render raw** | Measured, and negative. A list-of-objects becomes an `object` selector with `multiple: true`, and `ha-selector-object` labels its fields `fields[name].label \|\| name` — the converter sets no `label` and no `translation_key`. The `fields:` translations are shipped and validated (they are the shape Supervisor's own schema defines) but on frontend 20250925.1 they do **not** reach the screen. The `inverters` label and description themselves do |
+
+`test_translations.py` is what stops this rotting: a translation naming an
+option that does not exist, or an option with no translation, fails CI — in
+either direction, and the check is mutation-tested both ways.
+
 ### Sources
 
 | option | required | meaning |
@@ -78,9 +102,20 @@ inverters:
     setpoint_entity: number.goodwe_b_setpoint_w
     soc_entity: sensor.goodwe_b_soc
     batt_entity: sensor.goodwe_b_battery_power
-    max_w: 3000
+    max_w: 4600
 ```
 
+⚠️ **The 4600 W is inverter B's *datasheet* figure, not a measured one.** B is a
+GoodWe GW5048D-ES (serial `55048ESU22AW0992`, identified 2026-09-04) whose
+datasheet gives max charging and discharging power as 4600 W; with nothing
+connected to its PV inputs the battery path is the ceiling, not the 5000 VA AC
+nameplate. The datasheet prints that number under *Battery Input Data*, so it
+may be a DC figure, while `max_w` is graded against register `0x0518` — the
+inverter's own **AC** power. If it is DC the AC-side ceiling is nearer 4324 W.
+`max_w: 4600` is still the right thing to configure, because the freeze rail is
+`min(max_w, dev_max)` and the device range read off the unit is what binds.
+`goodwe/NOTES.md` §1.1b records both readings and picks neither.
+
 | per-entry key | required | meaning |
 |---|---|---|
 | `name` | yes | Short identifier. It namespaces this unit's SAFETY-02 latch, heartbeat and write bookkeeping in the add-on's state file, so **two units may not share one** |
@@ -131,6 +166,53 @@ in the log rather than silent, but it is an outage until someone puts the
 single-inverter entity back in that field. **Before downgrading, write down the
 `setpoint_entity` of the unit you want to keep running.**
 
+### What appears in Home Assistant at two inverters
+
+**Nothing you already have changes.** The eight entities this add-on has always
+published — `Setpoint`, `Grid power`, `Battery power`, `Battery SoC`,
+`Circulating power`, `Maintenance phase`, `Controller status`, `P1 sample age` —
+keep their device, their `unique_id`s and therefore their **entity ids and their
+whole recorded history**. At a roster of one, nothing new is announced at all:
+no second device, no renamed entity, not one added topic.
+
+Declare a second inverter and **four rows per unit** appear beside them:
+
+| per-unit row | what it is |
+|---|---|
+| `Setpoint` | this unit's own share of the site target — the number its heartbeat re-emits |
+| `Battery power` | this unit's own reading, `+` = discharging |
+| `Battery SoC` | **this** pack. The site `Battery SoC` row is the *emptiest* pack, which may be the other one |
+| `Sign latch` | this unit's SAFETY-02 latch: `tripped` or `clear` |
+
+⚠️ **The devices are deliberately asymmetric, and it is not an oversight.** The
+first inverter's rows are added to the **existing** *GoodWe* device; every later
+inverter gets its **own** device (*GoodWe Inverter B*), shown in Home Assistant
+as connected via the controller. Home Assistant composes an entity id from the
+**device name plus the entity name**, so giving the first inverter a device of
+its own would rename every entity you already have — and because HA keeps the id
+it composed at first discovery, you would get a new entity beside a dead one:
+the history stays on the old id and every dashboard, template and automation
+naming it silently stops updating. The entity ids come out symmetric anyway —
+`sensor.goodwe_inverter_a_battery_power` beside
+`sensor.goodwe_inverter_b_battery_power`.
+
+**Do not rename the device.** Not in this add-on, and not in Home Assistant's
+device page. It is half of every entity id, including
+`sensor.goodwe_p1_sample_age`, which the ESP32's stale-input watchdog subscribes
+to; a rename disarms that guard by leaving it waiting for a state that never
+arrives, and it fails silently and looks correct.
+
+**`Grid power` and `P1 sample age` stay site-scoped and are announced once.**
+There is one P1 meter and one grid connection; a per-inverter copy would invent
+two of a thing there is one of, and `P1 sample age` is a safety input. Same for
+`Circulating power` (it is a property of the *set* of inverters), the controller
+status, the maintenance phase and the capacity-tariff peak.
+
+⚠️ **Two roster names that differ only in punctuation or case** — `inverter-b`
+and `Inverter B` — are two names to the validator and one id once slugged. The
+add-on gives the second one a `_2` suffix so nothing collides, but the ids you
+get then depend on roster order. Give your inverters plainly different names.
+
 ### P1 meter ingestion
 
 `meter_entity` above expects one signed sensor, which usually means a template
@@ -213,6 +295,42 @@ the P1 sample already went stale. Size the pair together: the ESP32's own
 watchdog commands 0 W after ~30 s of silence from this add-on regardless, and
 that layer is unaffected by either option.
 
+#### How long a FROZEN inverter power register takes to reach 0 W
+
+A third clock, and it is a different failure from the one above: the entity is
+still there and still answering — it has simply stopped changing. Before
+SAFETY-37 that read as a healthy measurement for ever, which is what happened on
+2026-09-02 (HW-01): a value held for 6 h 25 m while the pack drained to its
+floor, and every detector read healthy throughout.
+
+`Inverter.batt` — the inverter's own AC power, register `0x0518` — is now
+withheld from the control path when **all three** of these are true:
+
+| | |
+|---|---|
+| the reading has not changed for | **35 s** |
+| **and** the command standing on that inverter is over | **250 W** |
+| **and** that command has travelled, since the reading last moved, over | **250 W** |
+
+All three, because a converged site legitimately repeats one power figure for
+minutes — measured at up to **263 s** over 30 days of this house's own meter —
+and a site at rest is not owed movement. It is only when the controller has
+*asked the inverter to move* and the register has not answered that the reading
+is treated as missing.
+
+**A withheld reading is a MISSING INPUT**, so it joins the `stale_input_s` clock
+above: 35 s to withhold, then 15 s of hold, then 0 W. It clears itself the
+instant the register reports a different value — one watt is enough, and this
+register dithers ±1 W while holding — so a working inverter clears it on its
+next 10 s publish. There is **no option to configure**: the 35 s is derived from
+the ESPHome publish interval and the two watchdog windows it has to stay inside,
+and the add-on's own checks refuse a value that does not.
+
+⚠️ **What this does NOT catch: a register whose value is WRONG rather than
+STOPPED**, including a dead publisher whose last two samples happen to
+alternate. Detecting that needs an arrival stamp inside the ESP32 firmware
+itself, which is TEL-06.
+
 There is **no fallback to an inverter-side power figure**, deliberately. The
 inverter's own AC power tracks its battery almost perfectly and the real meter
 hardly at all, so a controller that failed over to it would be regulating
@@ -350,12 +468,12 @@ behind it would trip the firmware watchdog on a system that is working fine.
 |---|---|---|
 | `max_w` | 2000 | Hard limit on what may be commanded. Start low, raise after commissioning. **Not read when `inverters` is declared** — each entry carries its own, and the site ceiling is their sum |
 | `gain` | 0.6 | Correction per cycle. **At the limit — do not raise** |
-| `slew_w` | 1000 | Maximum change per cycle |
+| `slew_w` | 0 | Largest change in one cycle. **0 means follow the rail** - `max_w / 9`, i.e. the loop takes the plant's own measured ~18 s settling time to cross its whole output range at the 2 s tick the live install runs. 222 W at `max_w: 2000`, 556 W at 5000, 1067 W at a ~9600 W two-inverter site. A fixed number is accepted and never silently reduced, but one FASTER than the rail implies is refused at startup (SAFETY-39): `slew_w: 1000` against `max_w: 5000` crossed the rail in 10 s against an 18 s plant, and on 2026-09-05 drove the meter from 3.4 kW of export to 2.8 kW of import |
 | `deadband_w` | 15 | Ignore errors smaller than this |
 | `target_grid_w` | -10 | What the meter should rest at. Negative = a slight export |
 | `step_w` | 10 | Quantisation |
 | `saturation_w` | 500 | Divergence that counts as "the inverter is at a limit" |
-| `saturation_cycles` | 3 | How many consecutive cycles before freezing. A cycle is one meter update or `cycle_floor_s`, whichever comes first - see the note below. **Do not set to 1** |
+| `saturation_cycles` | 3 | How many consecutive cycles before freezing. A cycle is one meter update or `cycle_floor_s`, whichever comes first - see the note below. **Do not set to 1**. Every value this file accepts (1-10) is below the freeze's own release bound of 12 cycles, so no accepted setting can stop the block engaging - see SAFETY-13, below |
 | `integrator_max_w` | 0 | Bound on the loop's accumulator, and 0 means "same as `max_w`". Caps how much stale error can be waiting to unwind when the sign flips. **Do not raise it above `max_w`** - the output clamp already bounds what is commanded, so the only thing extra headroom buys is more cycles of wrong-direction power after every saturation event. Lowering it below `max_w` is the useful direction |
 | `heartbeat_s` | 10 | Refresh interval; must stay well under the firmware watchdog |
 | `cycle_floor_s` | 15 | The longest the loop may go without evaluating. A deadline on the gap between cycles, reset by every cycle — on a healthy meter it never elapses and changes nothing. Raise it only if your meter is slower than ~10 s; it must stay under `meter_max_age_s`, past which there is no reading to evaluate anyway |
@@ -510,6 +628,94 @@ correct toward that wrong value instead of holding a stale command. It is bounde
 happened to a lying meter whose value merely jittered — bit-exact repetition was never a
 safety property.
 
+#### When the freeze lets go, and when it deliberately never does (SAFETY-13)
+
+While the loop is frozen the command's **magnitude may fall but never rise**. That is
+the anti-windup rule, and at `prev_w == 0` it reads as a refusal to *start*: with
+nothing commanded there is no magnitude left to fall, so a charge cannot begin. That
+refusal is deliberate. Commanding 0 W while the inverter reports hundreds of watts
+means something is driving the actuator that this add-on did not ask, and starting to
+push power the other way into it is how two controllers end up fighting over one
+actuator — the configuration §1.5 of the specification rules out.
+
+**What was missing was an end to it.** Nothing cleared the block: not the error growing,
+not the integrator moving, not time. The exit is now explicit, and *which* freezes get
+one is the decision:
+
+| the inverter is… | can it clear itself? | what happens now |
+|---|---|---|
+| doing **less** than the command, in the command's own direction — a cold pack, a curtailment, an export cap | **yes.** The command is pinned at something the inverter can reach, so it catches up and the freeze clears | unchanged: frozen for as long as it lasts, with no exit |
+| doing something **outside** what the command can explain — overshooting it, or the opposite sign | **not necessarily.** If another writer is on the actuator, clearing the freeze needs the inverter to track *our* command and the other writer is what stops it, so nothing ends it | the freeze releases once the divergence has outlasted the plant that could otherwise have explained it — see *what `freeze-released` actually tells you*, below, because this row is also where our own ramp lands |
+
+The second row's threshold is the plant's own measured settling time — **the slower of
+the two directions it was measured in.** The 2026-08-22 step test timed the same 1.78 kW
+step both ways: about 18 s to settle going up, about 23 s coming back down. 23 s is the
+one that belongs here, because the question this bound answers is *how long may the plant
+still be the explanation*, and the safe answer is to keep believing the plant for as long
+as the plant has ever been seen to take. At the measured 2 s meter tick that is
+**12 cycles** (`control.py`, `SETTLE_CYCLES`).
+
+⚠️ **The first version of this feature used 18 s, and 9 cycles was wrong in the direction
+that accuses.** Nine cycles is three short of the plant's own down-ramp, so an ordinary
+load step on a **single** inverter — the command falling through zero while the pack is
+still coasting the old way — could produce `freeze-released` with nothing else on the bus
+at all. Driven in the container against a model of the measured plant, one inverter and
+no second writer anywhere: over 272 load-step pairs the 9-cycle bound produced a release
+in 62 of them and the shipped 12-cycle bound in 2.
+
+**Releasing the output freeze does not unfreeze the loop.** The *integrator* freeze is
+untouched, so the command is free to move only as far as an accumulator that stopped
+accumulating cycles ago, one slew step per cycle. Measured on the simulator at the live
+install's shape (`max_w 5000`, `slew_w 400`, `target_grid_w -10`), with another writer
+holding the pack at +700 W and 2 kW of export standing: the command holds at 0 W while
+the counter climbs, starts on the **twelfth** saturated cycle, walks 0 → −400 → −800, and
+settles at **−1190 W** against a frozen integrator of −1194 W — not at the 5000 W rail.
+Before this change the same run held 0.0 W on every cycle, for as long as the other
+writer stayed.
+
+⚠️ **The site still does not reach its target in that state, and it is not supposed
+to.** What the exit buys is that the battery stops being idle while the site exports;
+what it does not buy is correct regulation against an actuator somebody else is also
+writing to. A standing grid error with another writer on the bus is the symptom of a
+configuration this add-on refuses to support, not a tuning problem.
+
+#### What `freeze-released` in the action log actually tells you
+
+**It says: the inverter's power did not match the command for longer than this plant has
+ever been measured to take to settle.** That is all it says. It is a reason to go
+looking; it is not a finding, and in particular it is **not** proof that a second writer
+exists.
+
+The test behind it compares the reading against **one cycle's** command, and the pack
+carries more than one cycle of history. So our own power, arriving late, can look like
+somebody else's:
+
+- **A big, fast load step is the ordinary innocent cause.** The command falls through
+  zero while the pack is still coasting in the old direction, and for a few cycles the
+  reading has the sign the command *used* to have. Measured, one inverter, nothing else
+  on the bus: eight cycles after a +1990 W command the command was 0 and the pack still
+  read +522.3 W.
+- **A plant slower than the one that was measured does it too.** The 12-cycle bound is
+  derived from a 23 s down-ramp. A colder or larger pack that takes longer than that will
+  produce releases on its own, and no constant read off the 2026-08-22 measurement can
+  prevent it. In the same container sweep, holding the bound at 12 and lengthening only
+  the plant's down-ramp, single-inverter releases went from 8 of 320 scenarios at the
+  measured 23 s to 59 of 320 at 34 s and 268 of 320 at 50 s.
+
+**So, in order:** if you see `freeze-released` **once, during or just after a large load
+or PV swing**, that is most likely the loop's own ramp and needs nothing. If you see it
+**standing** — cycle after cycle, at a steady load, with a standing grid error the
+battery is not correcting — then look for the second writer: another controller, a
+scheduler in the inverter's own app, or an installer tool left connected. That is the
+configuration §1.5 of the specification rules out, and it is the one this exit exists to
+stop the loop stalling on forever.
+
+⚠️ **No `saturation_cycles` you can set removes the block.** This file accepts 1-10, and
+all of those are below the 12-cycle release bound, so the freeze always engages before
+its own exit is due. (The first version of this feature had the bound at 9, where a
+setting of 9 or 10 *did* silently delete the block; moving the bound to 12 closed that
+by construction rather than by warning about it.)
+
 #### Why `target_grid_w` is not zero
 
 The deadband is a one-way ratchet: any resting point inside it holds until
@@ -554,7 +760,7 @@ help - see "Why the tuning is what it is".
 | `peak_forecast_entity` | Quarter-hour demand forecast, for capacity-tariff markets. Empty = no cap |
 | `peak_cap_w` | The site's capacity-tariff target |
 | `peak_soc_floor` (20) | **The percent below which the capacity-peak guard will not discharge the battery.** ⚠️ It bounds **the peak guard only** — it is **not a pack-wide reserve**, and ordinary self-consumption discharges straight past it (SAFETY-25, see below). Not optional and not the same thing as `maintenance_soc_floor` |
-| `bms_soc_floor` (10) | The pack's **own** cut-out percent, the number the BMS enforces whatever you set above. `peak_soc_floor` must be **strictly above** it or the add-on refuses to start |
+| `bms_soc_floor` (10) | The pack's **own** cut-out percent, the number the BMS enforces whatever you set above. `peak_soc_floor` must be **strictly above** it or the add-on refuses to start. ⚠️ **At a declared `inverters:` roster this key moves INTO each entry and is REQUIRED there** (SAFETY-32): it describes a battery, and two packs of different models have different cut-outs, so one number for both protects the shallower pack with the deeper pack's BMS. Nothing is inherited — an entry that omits it is refused **by name** at startup, and the flat key below is then not read at all |
 | `price_now_entity`, `price_avg_entity` | Dynamic tariff. Empty = never force a paid grid top-up |
 
 On a capacity-tariff site the maintenance charge is capped by the headroom left

goodwe_controller/MUTATION.md

@@ -135,12 +135,24 @@ manufactures them from a **fixture**: the check runs, the assertion is
 evaluated, the sentence above it is true — and the numbers it compares are
 arranged so that the failure it describes could not have changed the answer.
 
-It is not hypothetical and it is not rare. EIGHT instances in two weeks; four
+It is not hypothetical and it is not rare. ELEVEN instances in two weeks; four
 were found by review, two - CFG-04's fixture pair - by an author's own mutation
 battery, which is the cheaper place, one by review again, in the one
 place nobody had thought to point the rule at: not a check in the suite, but a
-COMMITTED EVIDENCE ARTIFACT four documents cite - and the eighth INSIDE THE FIX
-WRITTEN TO CLOSE THE SEVENTH.
+COMMITTED EVIDENCE ARTIFACT four documents cite - the eighth INSIDE THE FIX
+WRITTEN TO CLOSE THE SEVENTH, the ninth inside the SITE HALF of the card
+that names the rule in its own text - and the TENTH INSIDE THE FIX WRITTEN TO
+CLOSE THE NINTH, for the second time in this list. See SAFETY-38 below: the
+check that closed it asserted a NUMBER and not the number's POSITION.
+
+⚠️ AND THE ELEVENTH IS IN A MEASURING INSTRUMENT RATHER THAN IN A CHECK, which
+is where the seventh was too. SAFETY-38 round 4's render probe - the thing that
+decides whether a mutation changed the SENTENCE and not merely the bytes -
+numbered each interpolated operand BY ORDER OF APPEARANCE. After a transposition
+the other operand takes the same number, so all thirteen mutant renders came back
+BYTE-IDENTICAL to the clean tree: the probe compared the swap against itself, and
+its output read exactly like "the edit is inert". Keying the value to the
+operand's NAME fixed it. Habit 16.
 
 ⚠️ **AND IT HAS NOW APPEARED IN SIX CONSECUTIVE CARDS.** The seventh instance,
 MAINT-05's, is the one that says why: the defect is not carelessness about
@@ -234,6 +246,65 @@ same place twice, the check is decoration.
   assertion cannot fail is exactly the thing this section is about. Two habits
   follow, and both are habit 5 and 6 below.
 
+* **SAFETY-38** — `main.py`'s
+  `site_standing = float(sum(standing.values()))`, the first argument of
+  SAFETY-30's latching site sign detector *and* SAFETY-18's `looks_frozen()`
+  input. `test_watchdog.py`'s `_sign_site` is the suite's **only** N≥2 site
+  fixture, and it runs shares of about **−2500 W each** — every one
+  individually over the 320 W gate it is configured with. On numbers like those
+  `sum`, the mean and `max(key=abs)` **all agree**, so the reduction could be
+  swapped for either of the other two and the site guard went **blind with the
+  whole suite green** — still commanding −500 W of charge into a +2500 W import at
+  t = 595 s with `following=True`. At a roster of **one** it is worse and it is
+  not a fixture defect at all: `sum == mean == max == the one share`
+  *identically*, so every such mutation is genuinely **equivalent** there and no
+  N=1 fixture could ever separate them. The fixture that separates them is the
+  one the detector exists for — **per-unit shares EACH BELOW the gate whose SUM
+  clears it** — and it is now `test_watchdog.py` part 9, at asymmetric ratings
+  so that all four candidate reductions give four **distinct** answers.
+
+  ⚠️ **AND THE CARD'S OWN SEARCH FOR ITS NEXT SURVIVOR FOUND ONE, WHICH IS THE
+  POINT OF ASKING.** Having built the fixture, the question *what mutation would
+  this NOT see?* produced `float(self.target)` — the arbiter's site target
+  instead of the sum of what stands on the wire — at **−11 B**, green across the
+  whole suite, because every fixture in the repository was built where the two
+  are the same number. They separate only when a device's reported range is
+  narrower than its `max_w`, since the `device` claim is filed **per actuator**
+  and never bounds the site target. Closed in the same commit, by a
+  counterfactual that asks for −500 W while −250 W stands.
+
+  ⚠️ **AND THEN THE FIX ITSELF WAS THE TENTH INSTANCE — A SUBSTRING WHERE THE
+  FAILURE WAS POSITIONAL.** The check written to pin the banner asserted
+  `f"{sum(...):.0f} W" in reason`: that **"−500 W" appears somewhere** in the
+  sentence. Swapping the detector's first two arguments
+  (`evaluate(site_standing, self.grid, …)` → `evaluate(self.grid, site_standing, …)`)
+  is a **ZERO-BYTE** edit that leaves both numbers in the string and moves each
+  into the other's slot — so the substring is still found, **in the meter
+  slot**, and the whole suite stayed green while the latching site-stopping
+  banner told the operator which instrument read what **exactly backwards**.
+  The fix is to assert the **ORDERED PAIR**,
+  `f"commanded {sum:+.0f} W against a meter reading {grid:+.0f} W"`.
+
+  ⚠️ **AND THE ELEVENTH WAS THE SAME DEFECT ONE CALL SITE OVER — THE ONE A
+  SHIPPED INSTALL CAN ACTUALLY SEE.** Round 2 pinned the operand order of
+  `SignWatchdog.evaluate()` at `main.py:1620`. That call site is the **site**
+  detector, and `test_watchdog.py` part 9c asserts it is **never armed at a
+  roster of one** — which is every install this add-on has. The **per-unit**
+  call at `main.py:1560` was left unpinned, and swapping its first two
+  arguments is the same **ZERO-BYTE** edit: `disagrees()` is symmetric in them
+  (`commanded_w * against_w < 0` with an `abs()` gate on both), so **no trip
+  decision can change** and the full 21-file suite stays green — measured. What
+  moves is five banner lines, including the one persisted to `sign_reason` and
+  re-read after a restart: *"commanded −1000 W against its own measured power
+  +1000 W"*, operands inverted, on the only sign-disagreement sentence a
+  one-inverter install can ever print. Closed in round 3 by the ordered pair on
+  **both** per-unit banners — the N≥2 `its own measured power` one and the N=1
+  `a meter reading` one — red on four named checks, green in the other twenty
+  files. **Habit 15 is what falls out of finding the same shape twice in the
+  same card.**
+
+  The general habits are **14** and **15** below.
+
 Note what these have in common with a masked rung: the mutation *runs*, and the
 suite is *honestly* green. Nothing in a purge, a fingerprint or a disassembly
 can see it, because the code under test really did behave identically on the
@@ -300,6 +371,221 @@ Cheap habits fall out of it, and all of them are now used in this repository:
    assert the **shape** of that second report, not only its verdict, so the
    check cannot silently revert to grading the first path.
 
+10. **A fixture of N members cannot separate two reductions that agree on N
+    members — so grade the FAMILY, and grade it from the SOURCE.** This is the
+    only lesson SAFETY-32 cost four review rounds to learn, and it generalises
+    past packs to every roster, list and window in this repository. Two packs
+    cannot tell `max` from `min` from first from last. Three cannot tell `max`
+    from `max(x[-2:])`. **The regress does not terminate in a fixture**: `[:1]`
+    needs two members, `[:2]` three, `[:3]` four, and adding one more member
+    moves the hole rather than closing it. Three things follow, and all three
+    are now in `test_peakguard.py` parts 12c2, 12g, 12i and 12j:
+    * the fixture is a **SET** — the extreme at every position of the roster,
+      not one roster with the extreme somewhere;
+    * the family table is **COMPUTED and PRINTED**, so a member no fixture kills
+      shows up as a named survivor and takes the check red, instead of being
+      absent from a list nobody re-derived;
+    * where the claim is an **IDENTITY** ("this roster", "this list"), pin it
+      **exactly on the AST** — `ast.unparse(arg) == "self.packs"` is false of
+      every slice, where `"self.packs" in src` is true of all of them. Where the
+      claim is **SEMANTIC** ("the maximum"), a shape pin would refuse honest
+      refactors, so report the unreached width **with its size** instead.
+
+11. **When a check of this shape is found, mutate its SIBLINGS before shipping
+    the fix.** SAFETY-32 was rejected three times for the same defect one step
+    over: the reduction, then the roster handed to it, then the reduction handed
+    to the *other argument of the same call*. Enumerating the family from the
+    AST and mutating each member took one afternoon and found **four more
+    survivors in code the card never touched** — three of SAFETY-30's
+    `any(i.sign_wd.tripped for i in self.inverters)` reductions, invisible
+    because the only fixture that reached them was a roster of ONE, where
+    `self.inverters[:1]` **is** `self.inverters`. Ask of every fix: *what is the
+    sibling of the thing I just hardened, and does any fixture separate it from
+    a slice of itself?*
+
+12. **When the same shape has been found twice, STOP CLOSING SITES AND BUILD
+    THE INSTRUMENT — and make it DISCOVER its own scope.** SAFETY-32 was
+    rejected four times, and each round closed exactly the site it was handed:
+    the reduction, then the roster handed to it, then the *sibling argument* of
+    the same call, then the same family one *module* over, in validate.py.
+    Round 4 did enumerate — and enumerated inside the `Controller` class,
+    because that is where the four known sites lived. **A hand-written scope is
+    the same defect as a hand-written fixture**: it is a check whose data cannot
+    reach the failure it names, and it goes on passing while the thing it was
+    supposed to cover sits in the file nobody added to the list. Round 5's pin
+    parses every `.py` under `app/`, seeds itself from ONE option key, and
+    propagates through returns, accumulator loops, attributes and *call
+    arguments* to find the roster wherever it went — 183 reductions across 9
+    modules. It rediscovered all four blockers without being told where to look,
+    and it named two modules the hand-written list would not have contained
+    (`maintenance.py`, `store.py`) while *omitting* one the list did contain
+    (`watchdog.py`, which is strictly per-unit and reduces over no roster at
+    all). **The list was wrong in both directions**, which is exactly what a
+    computed scope is for.
+
+13. **Say what the instrument CANNOT see, with sizes, in the same breath.** A
+    structural pin grades an **identity** ("this whole roster arrives"); it can
+    never grade a **meaning** (`min` vs `max` is a zero-byte edit and invisible
+    to it). Ship the pin AND the behavioural set, name the gap, and give every
+    unreached case its byte delta — `cycle()`'s undeliverable-unit log line
+    (+4 B, still green), a subscript by a *variable* rather than a constant, a
+    slice taken through an intermediate call, anything outside `app/`. **An
+    enumerated list with an honest gap is worth more than a claim of
+    completeness a reviewer falsifies in ten minutes**, and every round of this
+    card that claimed the latter was rejected for it.
+
+14. **An `in` test against a formatted sentence grades PRESENCE, never
+    ARRANGEMENT — so assert the ORDERED PAIR.** SAFETY-38 pinned the banner of a
+    latching, site-stopping alarm with
+    `f"{sum(_share38):.0f} W" in ...reason` — that `"-500 W"` appears
+    *somewhere*. Swapping the detector's first two arguments at the call site
+    (`evaluate(site_standing, self.grid, …)` →
+    `evaluate(self.grid, site_standing, …)`) is a **ZERO-BYTE** edit: both
+    numbers are still in the string, each in the other's slot. The substring was
+    still found — **in the meter slot** — the whole suite stayed green, and the
+    banner told the operator which instrument read what **exactly backwards**.
+    Whenever the property you mean is "**this** value went in **this** slot" — a
+    reason string, a log line, a notification, an MQTT payload — assert the
+    surrounding **literal text with the value embedded in its own position**
+    (`f"commanded {x:+.0f} W against a meter reading {y:+.0f} W"`), or assert
+    the fields **before** they are formatted. Two values that both appear in one
+    sentence can always be transposed by an edit that costs **nothing**, and
+    that no byte delta, no fingerprint and no shape pin can see. ⚠️ Note where
+    this one was found: **inside the fix written to close the previous instance
+    of the same family**, which is the second time in this list.
+
+    ⚠️ **AND THE FIX FOR IT WAS ONE CALL SITE WIDE, WHICH IS THE HALF WORTH
+    KEEPING.** The ordered pair went onto `main.py:1620`, the **site** detector
+    — armed only at N≥2, and part 9c asserts it is **absent at a roster of
+    one**. The identical swap at `main.py:1560`, the **per-unit** detector, was
+    still **ZERO BYTES**, still changed no decision, still left the 21-file
+    suite green — and it is the **only** sign-disagreement sentence a shipped
+    one-inverter install can ever print: *"commanded −1000 W against its own
+    measured power +1000 W"*, backwards, in the log, on the status page and in
+    `sign_reason` after the restart the latch is designed to survive. Measured
+    size: **main.py:1560, 0 bytes, 21/21 green.** So habit 14 is not "pin the
+    banner", it is **"pin every call site of the banner, and say which one the
+    shipped roster reaches"** — and habit 15 is how you find them all.
+
+15. **A SYMMETRIC PREDICATE MAKES ARGUMENT ORDER A PROPERTY OF THE MESSAGE
+    ALONE — so ENUMERATE THAT FAMILY BY MACHINE, and grade the CALL SITES, not
+    the function.** Where a callee is symmetric in two arguments, a swap at any
+    call site is invisible to every behavioural check **by construction**: not
+    "no fixture happens to separate them" but *no fixture can*. There is
+    nothing for a mutation battery to find, because the mutant and the shipped
+    tree take identical actions on every input. The only surface that moves is
+    the sentence, and the only check that can see it is one asserting the
+    **ordered pair** (habit 14) at **that** call site.
+    Three consequences, and all three are why this is its own habit:
+    * **The unit of coverage is the CALL SITE.** SAFETY-38 pinned
+      `evaluate()`'s operand order and still shipped the defect, because the
+      pin was on the call two lines below the one that matters. Ask of every
+      banner: *how many places call this, and which does the shipped roster
+      reach?*
+    * **The scope must be COMPUTED** — habit 12's argument, and SAFETY-38 is
+      its proof: the family was enumerated by hand twice and was short both
+      times. `tools/symmetric_message_scan.py` renames each parameter pair,
+      erases every formatted string, canonicalises the commutative operators
+      and iterates to a **fixpoint** over `app/` (the symmetry is usually one
+      call deep — `evaluate()` is symmetric only *through* `disagrees()`), then
+      classifies each sentence by where it GOES. A returned string may be a
+      **key** — swapping `store.unit_key(unit, key)` renames a store key, which
+      is behaviour and is MAINT-05's card — or a **sentence**, which is this
+      family.
+    * **Say what the instrument cannot see, with shapes** (habit 13). That scan
+      under-reports semantic symmetry no canonicaliser on its finite list can
+      spell; its second census, for sentences the CALLER builds, pairs only
+      expressions **one leaf apart** and never sees `%s`-style logging; it
+      covers only `app/`; and it **over-reports in exactly one way** — it
+      erases the sentence, so a swap that would make the FORMATTING itself
+      raise is scored as changing no decision. It prints all of that on every
+      run. The family, every member's call sites, and which of them are pinned
+      are in `DECISIONS/SAFETY-38-site-standing-pin.md` §7 — **with two
+      measured, still-open survivors named there rather than rounded off**,
+      both zero bytes and both 21/21 green.
+    * ⚠️ **AND THE SINK IS HALF THE SCOPE, WHICH IS HOW THE FIRST THREE ROUNDS
+      OF THIS SCAN MISSED THE PLACE THE CODEBASE ACTUALLY KEEPS ITS SENTENCES.**
+      The scan classified a sentence as operator-facing when it was **appended,
+      assigned to a `reason`-shaped name, or logged** — and every one of its 16
+      reported members was one of those. **None was RETURNED.** A method
+      formatting its own **attributes** and handing the string back —
+      `ClampResult.describe()`, `PeakDecision.explain()`, every reason-builder
+      in the tree — was outside all of it, and so were sentences handed to a
+      constructor as `reason=` or placed under a `"text"` dict key. Four
+      zero-byte survivors of a green 21-file suite were sitting there, two of
+      them on the alarm SAFETY-40 and SAFETY-41 are about. **The general form:
+      an enumeration is scoped by a SINK as much as by a PREDICATE, and a sink
+      list is a hand-written list like any other (habit 12).** Ask of any such
+      scan: *which syntactic forms does this call a message, and what does the
+      code under it actually use?*
+
+16. ⚠️ **AN INSTRUMENT THAT ASSERTS A COMPLETENESS IT DOES NOT HAVE IS WORSE
+    THAN NO INSTRUMENT, AND ITS BLIND-SPOT LIST IS PART OF THE CODE UNDER
+    REVIEW.** `tools/symmetric_message_scan.py` printed five honest gaps and a
+    census count, and a reader — including its author, twice — took the count
+    for the family. The gap that mattered, the RETURN sink, was **in none of the
+    five**. A gap list is not a disclaimer; it is a claim, and it is the claim
+    most likely to be believed because nothing else in the output argues with
+    it. Two consequences:
+    * **State what is NOT scanned, largest hole first, as a list of forms** —
+      not "this under-reports". The tool now names `%s`-style lazy logging
+      (`_LOG.error("… %s … %s", a, b)`, where the operands are *arguments*, so
+      no f-string census can ever see them), `.format()`/`%`/`+`/`.join()`
+      sentences, sentences that leave through a dict or dataclass, `yield`,
+      message attributes outside its own constant set, and everything outside
+      `app/`. Where the list is derived from a constant in the file, it is
+      **printed from that constant**, so the two cannot drift.
+    * **AND THE PROBE THAT GRADES THE MUTATIONS IS SUBJECT TO EVERY HABIT
+      ABOVE.** Round 4's render probe gave each interpolated operand a value by
+      **order of appearance** — so after a transposition the other operand took
+      the same number and **all thirteen mutant renders came back
+      byte-identical**, which reads exactly like *the edit changed nothing*.
+      Keying the value to the operand's **NAME** fixed it. That is habit 4, in
+      the measuring instrument: the fixture's own values were arranged so the
+      failure it was built to see could not change the answer. **Eleventh
+      instance of habit 4 in this file, and the second one in an instrument
+      rather than in a check.**
+
+17. ⚠️ **TWO TERMS OF A CONJUNCTION THAT MOVE TOGETHER IN EVERY FIXTURE ARE
+    ONE TERM AS FAR AS THE CHECKS ARE CONCERNED - TWELFTH INSTANCE OF HABIT 4,
+    and the third found by an author's own battery rather than by review.**
+    SAFETY-37's freshness gate is `unchanged >= 35 s AND |standing| >= 250 W
+    AND |travel| >= 250 W`. Deleting the MIDDLE term left every check in the
+    first draft green, because in all of them a command that had *travelled*
+    250 W had also *ended up* above 250 W: the fixture never separated the two,
+    so one of them was decoration as far as the suite could tell. The case that
+    separates them is a site being brought to REST - the register reaches its
+    new value on the same read at which the OLD command is still standing, so
+    the travel term alone reads 1300 W of unfollowed command while the site
+    sits truthfully at +5 W. Ask of every conjunction: **is there a fixture in
+    which each term is the ONLY one that is false?** If not, the suite cannot
+    tell an AND from an OR.
+
+18. ⚠️ **AN UNVERIFIED REVERT IS THE SAME DEFECT AS STALE BYTECODE, AND TWO
+    HARNESSES SHARING ONE BACKUP PATH IS THE WORST VERSION OF IT.** SAFETY-37's
+    sweep hit this twice, in ascending order of nastiness.
+    * A mutation's container run overran a two-minute command budget and the
+      wrapper was killed **between the edit and the `cp` that puts the file
+      back**, leaving `app/freshness.py` mutated on disk. Nothing announced it;
+      the next mutation's harness cheerfully fingerprinted and graded the mutant
+      *plus* a second mutation.
+    * Then two copies of the sweep were started - a scheduling mistake, not a
+      tool defect - and the harness kept its backup at the FIXED path
+      `/tmp/mut.bak`. One copy saved `app/main.py` there; the other restored it
+      **over `app/freshness.py`**. The result was a 238 KB `freshness.py` that
+      still parsed as Python, plus `main.py` left holding a live mutation. No
+      error, no warning, and the only reason it was noticed is that the tree
+      fingerprint did not match the recorded clean one.
+
+    Two rules, and the first is the cheap one:
+    * **Fingerprint after the revert, not only before the run.**
+      `tools/mutation_run.sh` prints the tree it is about to grade for exactly
+      this reason; the revert deserves the same treatment, and a mismatch is a
+      stop-everything result rather than a note.
+    * **A harness's scratch file must be unique per invocation** (`mktemp`), so
+      that two of it cannot silently overwrite each other's work. A fixed path
+      in a tool that edits source is a shared mutable global with a filename.
+
 And the mutation-table consequence: **a variant is not covered because a
 near-miss of it is.** DEV-02's table listed the *actuator* variant of the
 per-unit claim defect (`device`/`supervised` filed without `inv`), which the

goodwe_controller/app/circulation.py

@@ -122,6 +122,18 @@ CIRC_OPTION_DEFAULTS = {
     #     200 W -> 445.0 s     350 W ->  10.0 s    1000 W -> 5.0 s
     #     250 W ->  40.0 s     400 W ->   5.0 s    1700 W -> 0.0 s
     #
+    # ⚠️ SAFETY-39 MOVED THAT SCHEMA FLOOR FROM 50 TO 0, AND THE CAMPAIGN ABOVE
+    # WAS NOT RE-RUN. It does not have to be, and here is the argument rather
+    # than the assurance. What these windows are about is how long the command
+    # takes to CROSS ITS RAIL - the swept worst case is the SLOWEST crossing,
+    # which is `slew_w` at its floor, 5000/50 = 100 cycles. `slew_w: 0` means
+    # "follow the rail" and resolves to `SLEW_RAIL_FRAC * max_w`, which is
+    # exactly 9 cycles at EVERY rail by construction. So the new value can never
+    # be the slowest crossing at any `max_w`, and it is strictly inside the
+    # envelope this campaign measured. An explicit number still spans 50..5000
+    # and is unchanged. If `SLEW_RAIL_FRAC` is ever loosened past 1/100, this
+    # paragraph stops being true and the campaign has to be re-run.
+    #
     # THE KNEE IS AT 400 W and it is sharp. Below ~250 W a flapping load holds
     # the sensor above the threshold for MINUTES at a time - 505 s at 100 W -
     # and no window shorter than the 900 s billing quarter could tell that from

goodwe_controller/app/clamp.py

@@ -145,14 +145,94 @@ from datetime import datetime
 # nothing else in this add-on uses it. See "DISTINCT FROM SATURATION".
 REASON_CODE = "OUTPUT_CLAMP"
 
-# Re-assert the notification this often while the clamp stays engaged. 30 s is
-# the planning cadence (2.3), i.e. slow enough not to flood and fast enough
-# that a pinned loop is never quiet for a whole billing quarter.
-REASSERT_S = 30.0
+# Re-assert the notification this often while the clamp stays engaged.
+#
+# ⚠️ RAISED 30 s -> 150 s on 2026-09-05, and the reason is a REGIME CHANGE, not a
+# change of mind about the alarm. 30 s was the planning cadence (2.3), chosen
+# when a loop-side engagement was a rare event: `main.py`'s note at the action
+# log records "60 cycles of the §10.3 runaway produce 0 write-path engagements
+# and 2 loop-side ones". On the live install the counter reached 48 loop-side
+# ENGAGEMENTS in ~25 minutes of ordinary operation - roughly one cycle in six,
+# not a pinned rail, but far more often than a guard sized for 2-in-60 assumed -
+# and the owner received a persistent notification about it all day. ⚠️ NOT
+# because of the 30 s re-assert - see the block below; those notifications never
+# consulted this constant at all.
+#
+# ⚠️ BOTH FIGURES ARE ENGAGEMENT COUNTS; only the regime differs - 2-in-60 was
+# measured over a §10.3 RUNAWAY, 48-in-305 was ordinary running on the live
+# install. The 48 is read off the live log, not measured in this repo.
+#
+# ⚠️ AND RAISING THIS CONSTANT ALONE DID NOT FIX THAT FLOOD - review found it
+# and the first version of this change was wrong. At ~5 s cycles a 1-in-6
+# engagement leaves ~25 s of clean cycles between engagements, past
+# CLEAR_CYCLES x 5 s = 15 s, so the alarm DE-ASSERTED between almost every one
+# and came back as a fresh rising edge. The rising edge used to fire
+# unconditionally, so those notifications never consulted this constant at all:
+# 48 notifications at 30 s, and still 48 at 150 s. The fix was to rate-limit the
+# RISING EDGE too and let `last_alarm` survive a de-assert, so this interval
+# bounds the notification rate across episodes rather than only within one.
+# Measured on that same window afterwards: 51 episodes, 11 notifications.
+#
+# WHY the loop reaches its integrator bound so much more often than the guard's
+# author saw: `max_w` on the live install is 5000 W, while the loop's slew was
+# derived against a 1500 W clamp - admin/goodwe `NOTES.md` §"Simulated 2 kW load
+# step (gain 0.6, clamp 1500)". ⚠️ THAT DERIVATION IS IN THE OTHER REPO; nothing
+# in this one corroborates it, so do not go looking here. SAFETY-39 is the ticket
+# that re-derives it, and fixing that is what would stop the railing; this
+# constant only changes how often the alarm repeats.
+#
+# ⚠️ 150 s IS THE REQUIREMENT'S EDGE WITH MARGIN, AND THE CHECK NOW ENFORCES THAT
+# EDGE. `test_clamp.py` part 2 grades the cadence in wall-clock terms - a pinned
+# loop must speak at least MIN_PER_QUARTER = 5 times inside the 900 s quarter
+# that bills the capacity tariff - which caps this constant at 900/5 = 180 s.
+# Measured on the worst sliding 900 s window: 180 s earns 5 alarms, 181 s earns
+# 4. 150 s earns 6.
+#
+# ⚠️ THAT CHECK USED TO PERMIT 224 s, AND THE FIX SHIPPED WITH THIS COMMIT. Its
+# sweep starts at i=0, where the rising edge is free, so it measured one alarm
+# more than a real quarter earns. A later editor raising this to 200 s would have
+# had a green suite and a requirement quietly unmet. `test_clamp.py` now grades
+# floor(QUARTER_S / REASSERT_S) directly.
+#
+# ⚠️ MIN_PER_QUARTER = 5 IS A TEST-LOCAL INTEGER, not a spec figure - it exists
+# only in `test_clamp.py` and the CHANGELOG entry that introduced it. The 900 s
+# quarter IS system-wide (`tariff.py`, `freeze.py`, `DOCS.md`). So the 180 s
+# ceiling rests on one number a test author chose; if that number is ever
+# revisited, this constant moves with it.
+#
+# ⚠️ THIS IS A STOP-GAP AND DOES NOT MAKE THE ALARM CORRECT. The message still
+# calls the integrator bound a BUG SIGNAL and still pairs a request from one
+# moment with a `self.target` read at another - SAFETY-40. Nothing here is
+# suppressed: every engagement is still counted, the action-log row is written on
+# every engaged cycle regardless, and the rising edge of every episode alarms
+# unconditionally, so no alarm is DROPPED - only delayed.
+REASSERT_S = 150.0
 
 # Consecutive clean cycles before the alarm de-asserts (10.2 hysteresis).
 CLEAR_CYCLES = 3
 
+# ⚠️ SAFETY-41. Consecutive ENGAGED cycles after which an episode speaks even if
+# the notification budget is spent. THE ESCALATION EXISTS BECAUSE THE RATE LIMIT
+# ALONE DELAYS A RUNAWAY, and review measured it: a benign one-cycle clamp
+# followed by a continuous runaway held the runaway's first notification for up
+# to 140 s - one REASSERT_S minus a cycle. On the live install, where ordinary
+# railing spends the budget essentially all the time, a runaway arriving during
+# normal operation would be delayed with near-certainty. That is the "benign
+# noise suppresses the bug signal" shape this module's docstring is written
+# against.
+#
+# THE DISCRIMINATOR IS RUN LENGTH, and the two populations genuinely differ: the
+# live flood was runs of length ONE (engage, de-assert, engage), while a §10.3
+# runaway engages on EVERY cycle. So a sustained run speaks regardless of budget,
+# and scattered chatter does not.
+#
+# Measured, shipped-without vs shipped-with - it costs nothing it was protecting:
+#   live scatter flood (305 cycles, 1-in-6)   11 -> 11 notifications
+#   chatter 1-engaged/3-clean over 8000 s     50 -> 50 notifications
+#   pinned 900 s quarter (floor is 5)          6 ->  6 alarms
+#   runaway delay after a benign episode     140 s -> 10 s
+SUSTAINED_CYCLES = 3
+
 
 @dataclass(frozen=True)
 class ClampResult:
@@ -258,6 +338,10 @@ class ClampWatchdog:
         self.last_alarm: datetime | None = None
         self.reason = ""
         self.clean_cycles = 0
+        # SAFETY-41. Consecutive engaged cycles, and whether THIS episode has
+        # spoken yet - the two the escalation clause needs.
+        self.run_len = 0
+        self.spoken = False
 
     def note(self, engaged: bool, reason: str, now: datetime) -> bool:
         """Advance one cycle. True when the caller should raise the alarm.
@@ -269,26 +353,72 @@ class ClampWatchdog:
             self.engagements += 1
             self.clean_cycles = 0
             self.reason = reason
+            self.run_len += 1
             if not self.active:
                 self.active = True
                 self.since = now
                 self.episodes += 1
+                self.spoken = False
+                # ⚠️ SAFETY-41. THE RISING EDGE IS RATE-LIMITED TOO, and it did
+                # not used to be. It fired unconditionally, so a condition that
+                # engages and clears repeatedly raised one notification PER
+                # EPISODE no matter how fast the episodes came - and
+                # `REASSERT_S` never entered into it, because it only governs
+                # the still-engaged path below.
+                #
+                # That is the shape the live install actually produced: 48
+                # engagements in 25 minutes, scattered roughly one cycle in six.
+                # At a ~5 s cycle the gaps are ~25 s of clean cycles, which
+                # exceeds CLEAR_CYCLES x 5 s = 15 s, so the alarm DE-ASSERTED
+                # between almost every engagement and each one came back as a
+                # fresh rising edge. Measured on this class over that window:
+                # 48 episodes and 48 notifications at REASSERT_S = 30 - and
+                # still 48 at REASSERT_S = 150. Raising the re-assert removed
+                # NONE of them, because none of them came from the re-assert.
+                #
+                # So the interval now bounds the NOTIFICATION RATE rather than
+                # the repeat rate within one episode: `last_alarm` survives a
+                # de-assert, and a new episode speaks only if the interval has
+                # elapsed. ⚠️ NOTHING IS DROPPED. Every engagement is still
+                # counted, every episode still increments, the action-log row is
+                # still written on every engaged cycle, and a genuine runaway -
+                # which by definition keeps engaging - is picked up by the
+                # re-assert path within REASSERT_S. Delay, not loss.
+                if (self.last_alarm is None
+                        or (now - self.last_alarm).total_seconds() >= REASSERT_S):
+                    self.last_alarm = now
+                    self.spoken = True
+                    return True
+                return False
+            # ⚠️ THE ESCALATION. An episode that has not yet spoken because the
+            # budget was spent by an EARLIER, unrelated episode speaks anyway
+            # once it has engaged SUSTAINED_CYCLES times in a row. A runaway
+            # engages every cycle and reaches it; the scattered one-cycle
+            # railing that produced the live flood never does.
+            if not self.spoken and self.run_len >= SUSTAINED_CYCLES:
                 self.last_alarm = now
+                self.spoken = True
                 return True
             # Still engaged: re-assert on the slow cadence, not every cycle.
             if (self.last_alarm is None
                     or (now - self.last_alarm).total_seconds() >= REASSERT_S):
                 self.last_alarm = now
+                self.spoken = True
                 return True
             return False
 
+        self.run_len = 0
         if not self.active:
             return False
         self.clean_cycles += 1
         if self.clean_cycles >= CLEAR_CYCLES:
             self.active = False
             self.since = None
-            self.last_alarm = None
+            # ⚠️ `last_alarm` DELIBERATELY SURVIVES THE DE-ASSERT. Clearing it
+            # here is what made the next rising edge speak immediately however
+            # soon it arrived, which is the flood described at the rising edge
+            # above. The episode ends; the notification budget does not reset
+            # with it.
             self.reason = ""
             self.clean_cycles = 0
         return False

goodwe_controller/app/control.py

@@ -16,14 +16,199 @@ the short version is in the comments below. Do not "clean this up" - each rule
 exists because its absence produced a specific, observed failure.
 """
 
+import math
 from dataclasses import dataclass
 
+# ---------------------------------------------------------------------------
+# SAFETY-39. THE ONE RELATIONSHIP IN THIS FILE THAT IS NOT A NUMBER.
+#
+# ⚠️ WHAT WENT WRONG, because the shape of it is the reason this is a ratio and
+# not a constant. `slew_w: 1000` was derived on 2026-08-22 against a clamp of
+# 1500 W (goodwe/NOTES.md, "Simulated 2 kW load step (gain 0.6, clamp 1500)"),
+# and its stated justification was that it "puts most of the correction in the
+# first cycle WHILE STILL CAPPING HOW FAR THE LOOP CAN JUMP AHEAD OF THE
+# INVERTER". At 1500 W that sentence was true: 1000 W/cycle reaches the rail in
+# two cycles and the rail itself bounds the excursion.
+#
+# The rail then moved to 5000 W on the live install and the constant did not.
+# 1000 W per 2 s tick is 500 W/s, so the loop traverses its WHOLE OUTPUT RANGE
+# in 10 s against a plant NOTES.md §5.10 measured at ~18 s up / ~23 s down for a
+# 1.78 kW step. It commands its entire range before it can observe its answer to
+# the first step. Measured on the owner's system 2026-09-05 11:43-11:46: a real
+# 3.4 kW export, the setpoint ramping 380 -> 5000 in five ticks, the battery at
+# -5154 W against a 5000 VA inverter, and the grid pushed from 3.4 kW of EXPORT
+# to 2.8 kW of IMPORT - the loop manufactured the error it then chased.
+#
+# ⚠️ SO THE FIX IS NOT A NEW NUMBER. A number is what went stale. What is
+# written here is the RELATIONSHIP the 2026-08-22 sentence was really asserting:
+#
+#     THE LOOP MUST NOT TRAVERSE ITS FULL OUTPUT RANGE FASTER THAN THE PLANT
+#     TAKES TO SETTLE.
+#
+#     slew_w  <=  max_w * LOOP_TICK_S / PLANT_SETTLE_S
+#
+# `max_w` here is the SITE rail (main.py builds `Tuning(max_w=site_max_w)`, the
+# roster sum), so the bound moves with the roster and a second inverter cannot
+# re-open this by arriving. validate.py rule 10 refuses a configuration that
+# breaks it; `slew_w = 0` below means "follow the rail" and is the shipped
+# default, exactly as `integrator_max_w = None` already means "follow max_w".
+#
+# ⚠️ BOTH NUMBERS ARE WRITTEN OUT RATHER THAN THEIR QUOTIENT, AND THAT IS NOT
+# TIDINESS. The quotient is only meaningful in the regime the two were measured
+# in, and one of them is NOT a property of this code:
+#
+#   PLANT_SETTLE_S  is the inverter and the pack. goodwe/NOTES.md §5.10,
+#                   2026-08-22, a 1.78 kW kettle step driven from HA with a
+#                   plug that meters its own draw: ~18 s from the step to the
+#                   deadband going up, ~23 s coming down. 18 is taken because
+#                   it is the SHORTER of the two and therefore the LOOSER
+#                   bound - this is a refusal boundary, and rules 5 and 6 in
+#                   validate.py refuse the impossible case only, never "close
+#                   to the rail".
+#
+#   ⚠️ AND THAT CHOICE IS LOCAL TO THIS BOUND. §5.10 MEASURED THE STEP IN BOTH
+#   DIRECTIONS, so "the plant's settling time" is a PAIR and not a number, and
+#   which half is the safe one depends on which way being wrong hurts. Taking
+#   18 for a REFUSAL is right: the looser number refuses less. Taking 18 for a
+#   question of the form "how long does the plant remain a candidate
+#   explanation" is WRONG, because the looser number stops believing the plant
+#   too early - and there the answer is a false accusation. SAFETY-13 asks that
+#   second question and so reads PLANT_SETTLE_DOWN_S below, deliberately not
+#   this constant. Anything else added here has to say which of the two it
+#   means and why.
+#
+#   LOOP_TICK_S     is the METER, not this loop. `run_control()` runs a cycle on
+#                   a changed meter value or on `cycle_floor_s`, whichever comes
+#                   first, so the tick is the meter's own update rate. 2.0 s is
+#                   what the live install measured on 2026-09-05 (the setpoint
+#                   stepped +1000 W every 2 s), and it is the fastest meter this
+#                   project has ever run.
+#
+# ⚠️ AND THIS ONE IS NOT WRONG IN THE SAFE DIRECTION, WHICH IS WHY IT IS SAID
+# HERE. A SLOWER meter makes this bound conservative - it refuses some
+# configurations that would have been fine, which is visible immediately and
+# costs one edit. A meter FASTER than 2 s makes it loose by exactly that ratio,
+# and nothing in this add-on would say so. The tick cannot go below 1 s
+# (`run_control()`'s `await asyncio.sleep(1)` bounds the loop body), so the
+# worst case is a factor of two - but if a faster meter is ever fitted, this
+# constant has to be RE-DERIVED and not merely re-read. Compare
+# validate.FIRMWARE_INGEST_VETO_S, which carries the same kind of copy and can
+# only ever be wrong the other way.
+PLANT_SETTLE_S = 18.0
+LOOP_TICK_S = 2.0
+SLEW_RAIL_FRAC = LOOP_TICK_S / PLANT_SETTLE_S      # 0.111..., i.e. 9 ticks
+
+# The other half of the same measurement: the descent of the same 1.78 kW step,
+# ~23 s from a -1784 W export excursion back into the deadband (goodwe/NOTES.md
+# §5.10, the same run, the same day, the same plug). It is slower than the ramp
+# up, which is the ordinary asymmetry of a pack that is pushed one way and
+# coasts the other. Nothing above this line reads it; SAFETY-13 below does.
+PLANT_SETTLE_DOWN_S = 23.0
+
+# ---------------------------------------------------------------------------
+# SAFETY-13. HOW LONG THE PLANT STAYS A CANDIDATE EXPLANATION.
+#
+# The output freeze below stops the command growing while the inverter is not
+# following. Two completely different things produce that divergence and the
+# freeze cannot tell them apart on magnitude alone:
+#
+#   (a) THE PLANT HAS NOT CAUGHT UP YET, or it is at a limit - a cold pack, a
+#       curtailment, an export cap. Asking for more is pointless, and the
+#       freeze is right to hold. It also CLEARS ITSELF: the command is pinned
+#       at something the inverter can do, so the inverter catches up to it and
+#       `saturated_now` goes false.
+#
+#       ⚠️ AND (a) INCLUDES THE CASE `unasked_power()` BELOW CANNOT SEE AS (a):
+#       the command has fallen THROUGH ZERO and the pack is still coasting in
+#       the old direction, so the reading has the sign the command used to have
+#       and not the one it has now. That is this loop's own power, arriving
+#       late. It is the reason the time bound is what does the work here and
+#       the predicate alone is not enough.
+#
+#   (b) SOMETHING ELSE IS DRIVING THE ACTUATOR - the §1.5 non-goal, two writers
+#       on one actuator. The freeze CANNOT clear itself here, because clearing
+#       it needs the inverter to track OUR command and the other writer is what
+#       stops it. Nothing ends this but the other writer going away.
+#
+# ⚠️ SO THE BOUND IS ONLY EVER A REASON TO STOP BELIEVING (a). It does not
+# establish (b) and nothing below claims it does: what it says is that the
+# plant has run out of alibi, and (b) is then the only explanation this loop
+# has left - not the only one there is. Everything downstream of the release is
+# written to be safe when that inference is wrong, because sometimes it is.
+#
+# Case (a) is bounded by the plant, and the plant was measured:
+#
+#     SETTLE_CYCLES = ceil(PLANT_SETTLE_DOWN_S / LOOP_TICK_S)
+#
+# ⚠️ THE **DOWN** NUMBER, AND THE DIRECTION IS THE WHOLE POINT. §5.10 measured
+# the same step both ways - 18 s up, 23 s down - and SAFETY-39 takes 18 because
+# 18 is the LOOSER bound for a REFUSAL. This is the opposite job. Here the
+# question is "how long may the plant still be the explanation", and the
+# conservative answer is the LONGER of the two: believe the plant for as long
+# as the plant has ever been observed to take. Deriving this from 18 gives 9,
+# which is three cycles SHORT of the plant's own measured down-ramp - and being
+# short here does not refuse anything, it ACCUSES. Measured, single inverter,
+# no second writer anywhere, 1280 closed-loop scenarios: at 9 the exit fires in
+# 113 of them and at 12 in 24. The direction of that error is why the pair is
+# now two named constants instead of one.
+#
+# ⚠️ AND IT IS NO LONGER THE RECIPROCAL OF SLEW_RAIL_FRAC. It was, at 9, and
+# that coincidence read as a derivation - two different questions that happened
+# to share an answer while both were being asked of the same half of a two-
+# sided measurement. They are 9 and 12 now. If they ever coincide again it is
+# arithmetic, not agreement.
+#
+# ⚠️ IT INHERITS SAFETY-39's CAVEAT ABOUT LOOP_TICK_S, in the opposite
+# direction, which is why it is repeated rather than cross-referenced. A meter
+# SLOWER than 2 s makes these 12 cycles cover MORE than 23 s, so the freeze
+# holds longer than the plant needs: that costs energy - see the case in
+# DOCS.md - and never safety. A meter FASTER than 2 s makes them cover LESS,
+# so the freeze can release while the plant is genuinely still moving. That one
+# is bounded twice over and by neither this constant nor luck: the INTEGRATOR
+# freeze is not released with the output freeze, so the command can only reach
+# the integrator's frozen value, and the output clamp bounds that in turn.
+#
+# ⚠️ AND A PLANT SLOWER THAN THE ONE THAT WAS MEASURED DOES THE SAME THING,
+# which no constant derived from a measurement can fix. In the same 1280
+# scenarios, holding the bound at 12 and lengthening only the plant's down-ramp
+# past the measured 23 s, the exit starts firing again on a single inverter:
+# 8/320 at 23 s, 59/320 at 34 s, 268/320 at 50 s. A re-measured plant means a
+# re-derived constant here, exactly as for the two above it.
+SETTLE_CYCLES = math.ceil(PLANT_SETTLE_DOWN_S / LOOP_TICK_S)  # 12
+
+# The saturation counter's ceiling, one above the longest bound read from it. A
+# counter capped BELOW that bound would silently make the bound unreachable -
+# i.e. delete the exit condition - so it is written against SETTLE_CYCLES and
+# not as a literal, and it moves when SETTLE_CYCLES moves.
+#
+# ⚠️ IT WAS 10, WHICH IS ALSO config.yaml's MAXIMUM FOR `saturation_cycles`,
+# AND THAT COLLISION IS GONE. At a bound of 9 the largest accepted
+# `saturation_cycles` (10) sat ABOVE the exit, so a legal configuration could
+# push the freeze's engagement past its own release and the no-start block
+# stopped existing. At 12 every accepted value 1..10 is strictly below the
+# bound, so the freeze always engages before its exit is due and no accepted
+# configuration can delete the block. `test_control.py` pins that at the schema
+# edge rather than in prose, because it is a property of two files agreeing.
+_SAT_COUNT_CAP = SETTLE_CYCLES + 1                           # 13
+
 
 @dataclass(frozen=True)
 class Tuning:
     gain: float = 0.6
     max_w: float = 2000.0
-    slew_w: float = 1000.0
+    # SAFETY-39. How far the command may move in one cycle. ⚠️ 0 MEANS "FOLLOW
+    # THE RAIL" - `SLEW_RAIL_FRAC * max_w` - and it is the default and the
+    # recommended setting, for the reason written at the top of this file: a
+    # fixed number here is a constant that outlives the rail it was derived
+    # against, and that is the defect measured on the live system on
+    # 2026-09-05. Read `slew_limit_w()`, never this field.
+    #
+    # It stays settable, because slower than the rail implies is a legitimate
+    # and sometimes necessary choice - the live install has run an explicit
+    # 400 W since 2026-09-05 12:00 - and because `slew_w` is an option an
+    # operator already has. FASTER than the rail implies is what validate.py
+    # rule 10 refuses.
+    slew_w: float = 0.0
     deadband_w: float = 15.0
     step_w: int = 10
     saturation_w: float = 500.0
@@ -83,6 +268,93 @@ class Decision:
     clamped: bool = False
 
 
+def slew_limit_w(tuning: Tuning) -> float:
+    """How far the command may move this cycle, in W. Always positive.
+
+    ⚠️ THE ONE READER OF `Tuning.slew_w`, and everything else must come through
+    here. `slew_w = 0` means "follow the rail" and resolves to
+    `SLEW_RAIL_FRAC * max_w`, which is the whole of SAFETY-39: the limit is a
+    RATIO to the rail, so raising `max_w` moves it and cannot leave it behind.
+    A caller that read the field directly would see 0 and apply no limit at all
+    - the exact opposite of the setting's meaning - which is why this exists as
+    a function rather than as a comment telling people to remember.
+
+    ⚠️ AND IT IS NOT CLAMPED TO THE BOUND. An explicit `slew_w` above the rail
+    fraction is refused at STARTUP by validate.py rule 10, not silently reduced
+    here. Silently reducing it is the failure this whole module's docstring is
+    about - an operator's stated number quietly meaning something else - and
+    validate.py's own docstring calls it case (a).
+    """
+    if tuning.slew_w:
+        return abs(float(tuning.slew_w))
+    return SLEW_RAIL_FRAC * abs(float(tuning.max_w))
+
+
+def unasked_power(prev_w: float, actual_w: float, saturation_w: float) -> bool:
+    """True when `actual_w` cannot be explained by THIS cycle's command not being met.
+
+    SAFETY-13. The one question the saturation magnitude test cannot answer:
+    is the inverter FAILING TO REACH what we asked, or is it doing something
+    the command in front of it does not account for?
+
+    ⚠️ THE ANSWER IS PHYSICAL, NOT STATISTICAL, WHICH IS WHY IT IS A PREDICATE
+    AND NOT A THRESHOLD. A limit can only make the inverter do LESS than the
+    command, in the command's own direction. It cannot make it overshoot the
+    command, and it cannot make it produce power of the OPPOSITE sign. So the
+    whole set of readings a limit can produce is the closed interval spanned by
+    0 and `prev_w`, widened by `saturation_w` for measurement noise, ramp lag
+    and the inverter's own idle draw.
+
+    ⚠️ WHAT IT DOES NOT SAY - AND AN EARLIER VERSION OF THIS DOCSTRING DID -
+    IS THAT ANYTHING OUTSIDE THE INTERVAL WAS PUT THERE BY SOMETHING OTHER THAN
+    THIS LOOP. THAT IS FALSE AND IT WAS MEASURED FALSE. This predicate has no
+    memory: `prev_w` is one cycle's command, while the plant carries every
+    command before it. Drive ONE inverter, with nothing else on the bus, from a
+    discharge down through zero, and the pack is still coasting in the old
+    direction after the command has crossed. Measured in the container, one
+    `compute()` against one plant: eight cycles after a +1990 W command the
+    command is 0 and the pack still reads +522.3 W, so
+    `unasked_power(0, 522.3, 500)` is True - and every watt of that 522.3 was
+    asked for by this loop. In 1280 single-inverter closed-loop scenarios with
+    no second writer in them at all, the exit built on this predicate fires in
+    24 of them.
+
+    So what it guarantees is exactly the sentence at the top: this cycle's
+    command does not account for this cycle's reading. What it CANNOT do is
+    tell "somebody else is writing" from "we are". That gap is the reason
+    SETTLE_CYCLES is derived from the plant's slower direction, why the caller
+    checks both, and why the reason string it produces is a place to start
+    looking rather than a finding.
+
+    Worked, at `saturation_w = 500`:
+
+        prev  +2000, actual   +700  ->  inside [0, 2000]     a limit. False.
+        prev  -5000, actual   -700  ->  inside [-5000, 0]    a limit. False.
+        prev      0, actual   +700  ->  outside [-500, 500]  unasked. True.
+        prev   -800, actual   +700  ->  outside [-1300, 500] unasked. True.
+
+    ⚠️ AT `prev_w == 0` THIS IS EXACTLY `saturated_now`, and that is not a
+    coincidence to be tidied away - it is the reason the freeze's zero case is
+    the one the card was written about. With nothing commanded there is no
+    interval left for a LIMIT to live in, so at zero this test cannot be
+    answered by "the inverter is not reaching what we asked" at all. It can
+    still be answered by "the inverter has not finished leaving what we asked
+    for LAST time", which is the coast-down above and is why zero needs the
+    time bound as much as any other `prev_w` does.
+
+    ⚠️ IT IS NOT A DETECTOR AND MUST NOT BE ALARMED ON. A saturated inverter
+    whose reading is stale, wrong-signed or simply noisy lands outside the
+    interval too, and so does our own ramp, above. All this predicate decides
+    is whether the output freeze gets an EXIT; being wrong about it costs at
+    most a bounded command that the frozen integrator and the output clamp both
+    still bound. SAFETY-30's `unit_sign_disagree_w` is the thing that alarms on
+    sign, and it is deliberately a different test with a different threshold.
+    """
+    lo = min(0.0, float(prev_w)) - abs(float(saturation_w))
+    hi = max(0.0, float(prev_w)) + abs(float(saturation_w))
+    return not (lo <= float(actual_w) <= hi)
+
+
 def compute(
     prev_w: float,
     grid_w: float,
@@ -130,7 +402,7 @@ def compute(
     # clockless; the remaining ceiling is that saturation_cycles expresses a
     # bound in seconds rather than an exact number of them.
     saturated_now = abs(prev_w - actual_w) > tuning.saturation_w
-    sat_count = min(sat_count + 1, 10) if saturated_now else 0
+    sat_count = min(sat_count + 1, _SAT_COUNT_CAP) if saturated_now else 0
     frozen = sat_count >= tuning.saturation_cycles
 
     # --- deadband ----------------------------------------------------------
@@ -231,7 +503,8 @@ def compute(
     if clamped:
         reason = "clamped"
 
-    slewed = max(prev_w - tuning.slew_w, min(prev_w + tuning.slew_w, target))
+    slew = slew_limit_w(tuning)
+    slewed = max(prev_w - slew, min(prev_w + slew, target))
     if slewed != target:
         reason = "slew-limited"
     target = slewed
@@ -243,8 +516,69 @@ def compute(
         # implementation: commanding 0 while the inverter reports >500 W means
         # something else is driving the bus, and that is not the moment to
         # start pushing power the other way.
-        target = min(target, prev_w) if prev_w > 0 else max(target, prev_w)
-        reason = "saturated-freeze"
+        #
+        # --- SAFETY-13: ...AND IT IS NOT THE MOMENT FOREVER EITHER ----------
+        # Everything above stands. What was missing is an END. Held at
+        # `prev_w == 0` this is a refusal to START, and nothing in this
+        # function or above it clears it - not the error growing, not the
+        # integrator moving, not time. Measured on release/1.0 @ c8dcb38, at
+        # the live install's shape (max_w 5000, slew_w 400, target_grid_w -10):
+        # a site resting in the deadband with another writer holding the pack
+        # at +700 W reaches sat_count 3 with the command at 0, and 0 W is then
+        # a FIXED POINT - a 2 kW export arriving afterwards leaves the command
+        # at exactly 0.0 W on every subsequent cycle, with the integrator
+        # standing at -1194 W the whole time.
+        #
+        # ⚠️ AND THE ZERO CASE IS NOT SPECIAL, WHICH IS WHY THE FIX IS NOT
+        # SPECIAL EITHER. The same run pinned at prev_w == -800 W, against its
+        # own integrator standing at -2388 W, for as long as it ran.
+        # `prev_w == 0` is only the instance where the pinned magnitude happens
+        # to be zero - i.e. where the standing cost is the whole of what the
+        # battery could have done.
+        # A rule written for the zero case alone would have left the other
+        # instances exactly as unbounded as it found them.
+        #
+        # ⚠️ WHAT DECIDES IS NOT HOW LONG, IT IS WHETHER THE FREEZE CAN EVER
+        # END ON ITS OWN. See SETTLE_CYCLES and `unasked_power()` at the top:
+        # a divergence a LIMIT could produce clears itself once the inverter
+        # catches up to the pinned command, so it needs no exit and gets none -
+        # unbounded, exactly as shipped. A divergence a limit CANNOT produce
+        # does not clear itself by being waited on, so it gets one.
+        #
+        # ⚠️ AND THAT IS NOT THE SAME SENTENCE AS "THE OTHER WRITER". An
+        # earlier version of this comment said the two conditions below fire
+        # only in case (b); they do not, and the sweep says so. Our own plant
+        # coasting through a command that has just crossed zero satisfies
+        # `unasked_power()` too, because that predicate compares against ONE
+        # cycle's command and the pack remembers more than one - measured, a
+        # single inverter with nothing else on the bus reaching this branch in
+        # 24 of 1280 closed-loop scenarios. `SETTLE_CYCLES` is what keeps that
+        # rare rather than routine (113 of the same 1280 at the old bound of
+        # 9), and it does it by believing the plant for as long as the plant
+        # has ever been measured to take. It is a bound on how long we wait,
+        # not a proof about what we found.
+        #
+        # ⚠️ SO THE RELEASE IS WRITTEN TO BE SURVIVABLE WHEN IT IS WRONG, and
+        # that is the paragraph below, not this one: what a false release costs
+        # is one slew step per cycle toward a frozen integrator. If it ever has
+        # to cost less than that, the thing to change is what happens after the
+        # release, not the confidence of the sentence before it.
+        #
+        # ⚠️ RELEASING IS NOT UNFREEZING. The INTEGRATOR freeze above is not
+        # lifted, and that is what makes this bounded rather than merely
+        # different: the command is free to move, but only as far as an
+        # integrator that stopped accumulating cycles ago, through the same
+        # slew limit as any other cycle. It buys back the standing error, not
+        # the rail.
+        #
+        # `reason` is authoritative here in a way it is not elsewhere in this
+        # function: nothing after this line writes it.
+        if unasked_power(prev_w, actual_w, tuning.saturation_w) \
+                and sat_count >= SETTLE_CYCLES:
+            reason = "freeze-released"
+        else:
+            target = min(target, prev_w) if prev_w > 0 else max(target, prev_w)
+            reason = "saturated-freeze"
 
     # --- quantise ----------------------------------------------------------
     # 10 W. The register is 1 W and the inverter reports at 1 W, but its

goodwe_controller/app/freshness.py

@@ -0,0 +1,385 @@
+"""SAFETY-37 - a reading that holds its last value and reads healthy.
+
+THE DEFECT, in one sentence: `hass.number()` returns a held value as a value,
+and nothing anywhere in this add-on distinguishes "the inverter reports 40 %"
+from "the entity still says 40 % because nothing has updated it since Tuesday".
+
+The architect pass of 2026-09-06 put three cards on one mechanism. This module
+is that mechanism; the other two are its consumers.
+
+  LAYER 1     `goodwe/master/goodwe-master-stage4-failsafe.yaml:690` - the
+  (TEL-06)    ingest-age veto tests the VALUE of `sensor.goodwe_p1_sample_age`.
+              A dead publisher leaves the entity frozen at a healthy number and
+              the veto can never fire. NOT FIXED HERE - it is firmware, it is on
+              the other side of a flash, and nothing in this module can reach
+              it. What it owes is written at the bottom of this docstring.
+  THIS ADD-ON `app/hass.py:69-82`, consumed by SAFETY-30's per-unit sign check
+  (SAFETY-37) and SAFETY-31's circulating-power sensor. Both read `Inverter.batt`
+              (register 0x0518) and NEITHER had a freshness gate of any kind.
+  THE EVIDENCE HW-01, 2026-09-02: SoC held 40 % for 6 h 25 m while the pack
+              drained to its floor. Every detector read healthy throughout.
+
+⚠️ AT N>=2 EVERY ONE OF THOSE READINGS DOUBLES, which is why this card is the
+one that had to build it: the per-unit sign check and the circulation sensor
+only exist at N>=2, and both are fed straight from `Inverter.batt`.
+
+
+WHAT CANNOT BE THE SOURCE OF TRUTH, AND IT IS NOT A DETAIL
+==========================================================
+Home Assistant's `last_updated` DOES NOT MOVE when a value is rewritten
+unchanged. Neither does `last_changed`, and this project measured that
+`last_reported` does not advance on a repeat on either serialiser either - see
+`p1.HomeWizardLocalSource`'s docstring, which records the ENV-01 rig measurement
+over 70 s of a frozen meter and an independent one against the live house.
+
+So a value-side timestamp out of Home Assistant is a "time since the number
+changed" sensor wearing an arrival sensor's name. Thresholding it is how a
+detector ends up unable to fire, which is TEL-06's defect exactly. That trap
+produced two false diagnoses on 2026-09-05, both by a reader who already knew
+about it, which is why it is written here in full rather than referenced.
+
+⚠️ AND THE CONVERSE TRAP IS THE ONE THIS MODULE HAD TO SOLVE. The add-on polls
+Home Assistant's state cache roughly once a second (`run_control()`'s
+`await asyncio.sleep(1)` bounds the loop body and `read_inputs()` runs every
+pass). While the entity exists, HA answers 200 with a number whether or not the
+publisher behind it is alive. So AN ARRIVAL AT THE ADD-ON IS NOT AN ARRIVAL FROM
+THE INVERTER, and an arrival age alone cannot see HW-01 at all.
+
+What IS arrival-stamped here, and what makes this module honest, is the clock
+the verdict is measured on: `changed_mono` is the MONOTONIC INSTANT OF THE
+ARRIVAL THAT LAST CARRIED A DIFFERENT NUMBER. Every term below is a fact about
+arrivals this process observed, on its own clock. Nothing is read out of a Home
+Assistant timestamp, and nothing would change if Home Assistant stopped
+publishing timestamps altogether.
+
+
+THE VERDICT, AND WHY IT IS A CONJUNCTION
+========================================
+A bare "unchanged for N seconds" threshold is not available, and that is
+MEASURED rather than feared. Over the committed 30-day capture of this house's
+own 1 W-resolution power entity - `scenarios/p1-net-30d-2026-08/`, 485,841
+samples straight out of Home Assistant's recorder, where a row exists only when
+the state string CHANGED, so the gap between two rows IS the unchanged duration
+every consumer saw:
+
+    longest unchanged run, 30 days   263.2 s   (held -899.0 W, 2026-08-11 17:04)
+    runs >= 35 s                     10 of 485,840   (0.0021 %)
+    runs >= 17 s                    386 of 485,840   (0.0794 %)
+
+Measured on 2026-09-06 by replaying that capture. A real power figure at 1 W
+resolution held ONE value for four and a half minutes with nothing whatever
+wrong. ⚠️ That is the METER's register, not 0x0518, and it is named as a
+surrogate rather than passed off as the thing: no 30-day capture of 0x0518
+exists, because that register is not in the recorder export. What it does
+establish - and this is all it is used for - is that the LEGITIMATE unchanged
+duration of a power entity in this house is minutes, so an unchanged threshold
+alone must be minutes, and minutes is three times too slow to protect consumers
+that trip at 75 s and 85 s. The conjunction is not a refinement; without it
+there is no admissible threshold at all.
+
+⚠️ AND EVERY ONE OF THOSE LONG RUNS HAPPENED UNDER AN UNMOVING LOAD. That is
+the way out, and it is the same shape `freeze.looks_frozen()` already uses for
+the meter (unchanged AND the command pinned at the rail). A reading is stale
+when it has not moved THROUGH A CHANGE IT WAS OBLIGED TO FOLLOW:
+
+    STALE  <=>  unchanged for >= UNCHANGED_S
+                AND |standing command now| >= MOVE_W
+                AND |standing command now - standing command when the reading
+                     last changed| >= MOVE_W
+
+0x0518 is the inverter reporting ITSELF and it tracks its own command: r = 0.998
+with battery power against r = 0.09 with the real meter (goodwe/NOTES.md §3.3),
+command and actual agreeing within 4 W once settled (§5.10, 2026-08-22), and the
+register dithering +/-1 W while holding (§5.11, same day). A unit told to move
+250 W and still answering the same integer watt cannot be tracking.
+
+
+THE BOUNDS - ONE PER SIGNAL, EACH WITH ITS DERIVATION
+=====================================================
+⚠️ ONE CONSTANT FOR BOTH SIGNALS WOULD BE USELESS ON SoC OR TRIGGER-HAPPY ON
+POWER, which is the third clause of the policy. They are separated here, and
+only one of them is WIRED - see `BOUNDS` below and the note on SoC.
+
+`batt` / 0x0518, S16, 1 W, published every 10 s
+----------------------------------------------
+  LOWER BOUND, 17.0 s, the fastest a healthy register can be OBLIGED to have
+  answered. Three terms, each read out of this repository on 2026-09-06:
+
+     6.0 s  the plant. goodwe/NOTES.md §5.9, measured 2026-08-22 with the poll
+            temporarily at 1 s and a 0 -> +500 W step: 26 W at +1.43 s, 469 W
+            (94 %) at +3.34 s, settled 507 W at +6.05 s.
+    10.0 s  the publisher. `firmware/goodwe-master.yaml:181`,
+            `update_interval: 10s` on the `modbus_controller` that carries both
+            0x0518 and 0x050E. A command that moves right after a poll is not
+            visible until the next one.
+     1.0 s  this add-on's own read period - `run_control()`'s
+            `await asyncio.sleep(1)`, which bounds the loop body that calls
+            `read_inputs()`.
+
+  UPPER BOUND, 75.0 s, the tighter of the two consumers this card must protect,
+  both read from `config.yaml` on 2026-09-06:
+
+    75 s   `circulation_hold_s` (config.yaml:512) - SAFETY-31 trips here.
+    85 s   `unit_sign_disagree_s` (config.yaml:451) - SAFETY-30's per-unit sign
+           check trips here.
+
+  A gate slower than either is a gate that hands its consumer the frozen number
+  and then explains afterwards. ⚠️ AND THAT INEQUALITY IS GRADED, NOT ASSERTED -
+  `test_freshness.py` part 6 reads BOTH ends out of the shipped `config.yaml`
+  and goes red if an operator's default moves under this bound.
+
+  35.0 s IS THE CHOSEN VALUE, and the admissible band is narrow enough that it
+  is nearly forced: at least 2x the 17.0 s floor (34.0) and at most half the
+  75.0 s consumer window (37.5) leaves [34.0, 37.5]. 35 is the integer in it.
+  ⚠️ DELIBERATELY NOT 30 AND NOT 60. 30 is `validate.FIRMWARE_INGEST_VETO_S` and
+  would read as a borrowed constant nobody re-derived; 60 is round, and a round
+  number here would be a guess wearing a measurement's clothes.
+
+  WHAT IT COSTS, stated rather than absorbed: a frozen 0x0518 on a unit that is
+  never asked to move 250 W is not detected by this module at all.
+
+  ⚠️ THAT COST IS BOUNDED FOR ONE CONSUMER AND NOT FOR THE OTHER, and an earlier
+  version of this note claimed both. TRUE for the per-unit sign check: no such
+  check can speak about that unit either, since `unit_sign_disagree_w` is 250 W.
+  FALSE for circulation. "Contributing at most 250 W" bounds the COMMAND - but a
+  frozen register's REPORTED value is unrelated to its command, and that is
+  precisely HW-01's shape: commanded ~0 W, register stuck on the last large
+  number. Measured in review: a unit frozen at -1200 W beside a healthy +900 W
+  sibling gives `circulating_w` = 1800 W against a 700 W floor, 2.6x over, with
+  no gate armed. So this gate is scoped to where the SIGN consumer can be misled;
+  the circulation consumer keeps an unbounded exposure below MOVE_W and that is
+  a known, stated gap rather than a covered one.
+
+`soc` / 0x050E, U16, 1 %, published every 10 s - STATED, NOT WIRED
+-----------------------------------------------------------------
+  ⚠️ THIS ROW IS THE POLICY'S ANSWER FOR TEL-08 AND IT IS NOT CONNECTED TO
+  ANYTHING. It is here because the third clause of the policy is "state each
+  bound and its derivation", and because a reader who finds only `batt` wired
+  would reasonably conclude SoC was forgotten. It was not; it needs a
+  corroborator this card cannot derive.
+
+  SoC CANNOT USE THE CONJUNCTION ABOVE. A pack resting at its floor holds one
+  percent for hours with nothing wrong - the card's own example - and the
+  standing command says nothing about it, because a command of 0 W is exactly
+  what a rested pack is given. The physically obliged movement for SoC is
+  ENERGY, not command travel: one percent of pack A is about 153.6 Wh (15.36 kWh
+  nominal, goodwe/NOTES.md §1.1b's table - ⚠️ NOMINAL and FROM DATASHEET, not a
+  measured usable capacity), so at pack A's 5000 W ceiling one percent takes at
+  least 110 s and at a realistic 1000 W about 553 s. The bound TEL-08 needs is
+  therefore "SoC unchanged while the integral of |battery power| since its last
+  change exceeded K x 153.6 Wh", and K cannot be chosen from anything written
+  down today: nobody has measured this pack's usable capacity, its BMS reporting
+  granularity, or how far its reported percent lags true state of charge.
+
+  So TEL-08 owes: that capacity measurement (or a defensible bound on it), the
+  integrator, and K. It does NOT owe a second freshness mechanism - `Freshness`
+  below takes its obligation term from the caller precisely so that an energy
+  integral can be handed in where command travel is handed in here.
+"""
+
+import time
+from dataclasses import dataclass
+
+# --- the three terms of the lower bound, each read out of this repository ----
+# See the module docstring for where each one is measured. They are separate
+# names rather than a literal 17.0 so that a reader who changes the firmware's
+# `update_interval` can find this file by grepping for the number they moved.
+PLANT_SETTLE_S = 6.0        # goodwe/NOTES.md §5.9, measured 2026-08-22
+PUBLISH_PERIOD_S = 10.0     # firmware/goodwe-master.yaml:181
+READ_PERIOD_S = 1.0         # main.run_control()'s `await asyncio.sleep(1)`
+BATT_OBLIGED_S = PLANT_SETTLE_S + PUBLISH_PERIOD_S + READ_PERIOD_S   # 17.0
+
+# The unchanged bound for register 0x0518. See the derivation above; the band is
+# [2 * BATT_OBLIGED_S, 0.5 * circulation_hold_s] = [34.0, 37.5].
+BATT_UNCHANGED_S = 35.0
+
+# How far the standing command must have travelled for the register to be
+# OBLIGED to have followed it.
+#
+# ⚠️ IT IS THE LARGEST ADMISSIBLE VALUE, NOT A SENSITIVITY PREFERENCE, and that
+# is what makes it a derivation. The gate has to arm everywhere a stale reading
+# could mislead a consumer; the earliest either consumer speaks is
+# `unit_sign_disagree_w`, 250 W (config.yaml:450), because below that
+# `watchdog.disagrees()` is False whatever the measurement says. Taking the
+# ceiling of the admissible range is what minimises spurious arming. A smaller
+# number would arm the gate in states where nothing downstream can be misled,
+# and every such arming is a spurious site stop bought for nothing.
+#
+# ⚠️ NOT A CONFIG KEY. CFG-03 tracks the places a default has to be kept in
+# step and this does not earn another one - it is derived from a default
+# `config.yaml` already carries, and `test_freshness.py` part 6 READS that file
+# and goes red if the two drift.
+MOVE_W = 250.0
+
+
+@dataclass(frozen=True)
+class Bound:
+    """One signal's freshness bound, and whether anything consumes it."""
+
+    signal: str
+    unchanged_s: float
+    move_w: float
+    wired: bool
+    derivation: str
+
+
+# ⚠️ THE POLICY AS DATA, AND THE `wired` COLUMN IS LOAD-BEARING. A reader must be
+# able to tell, without reading main.py, which of these bounds is actually
+# gating a consumer today. `test_freshness.py` part 7 greps the shipped app/ for
+# each row and refuses a row that claims to be wired and is not - and a row that
+# claims not to be and is.
+BOUNDS = {
+    "batt": Bound(
+        signal="batt (0x0518, AC power, S16, 1 W, 10 s publish)",
+        unchanged_s=BATT_UNCHANGED_S,
+        move_w=MOVE_W,
+        wired=True,
+        derivation="settle 6.0 + publish 10.0 + read 1.0 = 17.0 s floor; "
+                   "circulation_hold_s 75 s ceiling; band [34.0, 37.5]"),
+    "soc": Bound(
+        signal="soc (0x050E, pack SoC, U16, 1 %, 10 s publish)",
+        unchanged_s=float("inf"),
+        move_w=float("inf"),
+        wired=False,
+        derivation="TEL-08. Command travel is the WRONG obligation term for "
+                   "SoC - a rested pack holds a percent for hours under a 0 W "
+                   "command. The term is energy: >= K x 153.6 Wh through the "
+                   "pack since the reading last changed. K needs a measured "
+                   "usable capacity nobody has taken."),
+}
+
+
+class Freshness:
+    """One signal's arrival record, and the stale verdict it supports.
+
+    ⚠️ ARRIVAL-DRIVEN THROUGHOUT. Every clock reading this object ever makes is
+    handed to `submit()` by the caller at the moment a value arrived; nothing
+    here reads a clock of its own and nothing here reads a Home Assistant
+    timestamp. That is what makes the verdict replayable - `test_freshness.py`
+    drives real seconds through it without sleeping - and it is the difference
+    between this and the value-stamped veto TEL-06 is blocked on.
+
+    ⚠️ THE VERDICT LATCHES, AND WITHOUT THAT IT OSCILLATES AT ABOUT 1 Hz.
+    Declaring the reading stale makes `Controller.inputs_ok` False, which
+    commands 0 W (§11.1 rule 1), which drops the standing command below
+    `MOVE_W`, which un-arms the conjunction, which would return the held number
+    to the consumers - and round again every read. So the ONLY thing that clears
+    the latch is an arrival carrying a DIFFERENT number, which is exactly the
+    evidence the verdict was about. A register that is working clears it on its
+    next 10 s publish; a register that is not, does not.
+    """
+
+    def __init__(self, bound: Bound):
+        self.bound = bound
+        # The last number that ARRIVED, or None if the most recent read did not
+        # produce one. This is what `reading()` hands back when the gate is open,
+        # so a read failure is still an immediate None exactly as it is today.
+        self.last = None
+        # The number the reading is currently HOLDING, and the monotonic instant
+        # of the arrival that last carried a different one. `held` survives a
+        # failed read; the unchanged clock is about the value, not about our
+        # ability to fetch it.
+        self.held = None
+        self.changed_mono = None
+        # The standing command at that same instant. The conjunction compares
+        # against THIS, not against the previous cycle's command: what matters
+        # is whether the register has followed anything since it last moved.
+        self.standing_at_change = None
+        self.stale = False
+        self.reason = ""
+        self.arrivals = 0
+
+    def submit(self, value, standing_w, now_mono) -> None:
+        """One READ of this signal. `value` None means nothing arrived.
+
+        `value`       the number `hass.number()` produced, or None.
+        `standing_w`  what this controller currently has standing on this unit's
+                      wire, signed, + = discharge. None when nothing is known.
+        `now_mono`    the caller's monotonic clock, in seconds.
+
+        ⚠️ A FAILED READ IS NOT AN ARRIVAL AND IS NOT AN AGE EITHER. It clears
+        `last` immediately - which is byte-for-byte what shipping code does
+        today, a missing reading being a missing reading - and it leaves the
+        unchanged clock running, because the value has not changed and our
+        inability to fetch it is not evidence that it has.
+        """
+        if value is None:
+            self.last = None
+            return
+        value = float(value)
+        self.arrivals += 1
+        if self.changed_mono is None or value != self.held:
+            self.held = value
+            self.changed_mono = float(now_mono)
+            self.standing_at_change = (None if standing_w is None
+                                       else float(standing_w))
+            # Movement is the ONLY thing that clears the latch. See the class
+            # docstring on the 1 Hz oscillation this prevents.
+            self.stale = False
+            self.reason = ""
+        self.last = value
+        self._grade(standing_w, now_mono)
+
+    def _grade(self, standing_w, now_mono) -> None:
+        """The conjunction. Sets the latch; never clears it."""
+        if self.stale or self.changed_mono is None:
+            return
+        held_s = self.unchanged_s(now_mono)
+        if held_s < self.bound.unchanged_s:
+            return
+        # ⚠️ BOTH None GUARDS ARE FOR A CALLER THAT DOES NOT KNOW ITS OWN
+        # OBLIGATION YET, WHICH IS NOT `_read_unit`. `Inverter.standing_w()`
+        # always answers a float, so neither branch is reachable from the wired
+        # consumer today. They are here for TEL-08, whose obligation term is an
+        # energy integral that has nothing to say until it has a window - and
+        # "nothing to say" must withhold the verdict, not manufacture one.
+        if standing_w is None or self.standing_at_change is None:
+            return
+        standing_w = float(standing_w)
+        if abs(standing_w) < self.bound.move_w:
+            return
+        moved_w = abs(standing_w - self.standing_at_change)
+        if moved_w < self.bound.move_w:
+            return
+        self.stale = True
+        self.reason = (
+            f"STALE_READING: {self.held:+.0f} unchanged for {held_s:.0f} s "
+            f"while the standing command moved {moved_w:.0f} W to "
+            f"{standing_w:+.0f} W - the reading is not following, so it is "
+            f"reported as MISSING rather than as a measurement (limits: "
+            f"unchanged over {self.bound.unchanged_s:.0f} s, command over "
+            f"{self.bound.move_w:.0f} W and moved by over "
+            f"{self.bound.move_w:.0f} W)")
+
+    def unchanged_s(self, now_mono) -> float | None:
+        """Seconds since an arrival carried a different number. Status page."""
+        if self.changed_mono is None:
+            return None
+        return max(0.0, float(now_mono) - self.changed_mono)
+
+    def reading(self):
+        """What the consumers get: the value, or None when it cannot be trusted.
+
+        ⚠️ `None`, NEVER A HELD NUMBER, and never a zero. Both consumers already
+        do the right thing with None and neither could ever receive one:
+        `watchdog.SignWatchdog.evaluate` CLEARS its window on a None measurement
+        rather than accumulating it, and `circulation.circulating_w` returns None
+        for a roster with a missing term, which clears the circulation window
+        too. This module is the thing that was missing between them.
+        """
+        return None if self.stale else self.last
+
+    def note(self, unit_name: str) -> str:
+        """One line for the status page. Empty when there is nothing to say."""
+        return f"{unit_name}: {self.reason}" if self.stale else ""
+
+
+def monotonic() -> float:
+    """The clock this module's callers use, in one place so tests can find it.
+
+    ⚠️ `time.monotonic()`, not the wall clock, for `p1.P1Sample.age_s`'s reason:
+    an NTP step on a Raspberry Pi that has just found the network is routinely
+    minutes, and a freshness verdict computed across one would either fake a
+    stale reading or, worse, hide a real one.
+    """
+    return time.monotonic()

goodwe_controller/app/inverter.py

@@ -15,6 +15,11 @@ The scalars, and what each one was silently asserting:
                           SAFETY-24's pack floor and arbitrage's bounds. An
                           average lets the emptier pack be driven below its own
                           floor; a maximum parks the fuller one.
+  `bms_soc_floor`         SAFETY-32. ONE cut-out percent for every pack, and it
+                          describes A BATTERY. Two packs of different models
+                          have different cut-outs, so the flat key graded the
+                          shallower pack against the deeper one's BMS - wrong
+                          in the direction that empties a pack.
   `batt`                  ONE battery power into the anti-windup saturation
                           detector - see the SITE/UNIT note at the bottom of
                           this docstring, because this one goes the OTHER WAY.
@@ -117,6 +122,15 @@ import math
 from datetime import datetime
 
 from .clamp import ClampResult
+# SAFETY-37. The freshness policy, and the ONE place its bounds are written.
+# freshness.py imports nothing from this package, so the direction is one-way.
+from .freshness import BOUNDS, Freshness
+# CFG-03's ONE in-code mirror of config.yaml's SAFETY-24 defaults. Imported
+# rather than retyped: the flat-keys path below needs `bms_soc_floor`'s
+# shipped default and a literal here would be the fourth defaults site that
+# ticket exists to prevent. peakguard imports arbiter/control/tariff and none
+# of those imports this module, so the direction is one-way.
+from .peakguard import PEAK_OPTION_DEFAULTS
 from .store import unit_key
 from .watchdog import SignWatchdog, SignWatchdogConfig
 
@@ -170,7 +184,7 @@ class Inverter:
 
     def __init__(self, name, *, setpoint_entity="", soc_entity="",
                  batt_entity="", batt_invert=False, max_w=2000.0,
-                 store=None, sign_cfg=None):
+                 bms_soc_floor=None, store=None, sign_cfg=None):
         self.name = str(name)
         self.setpoint_entity = str(setpoint_entity or "")
         self.soc_entity = str(soc_entity or "")
@@ -179,6 +193,19 @@ class Inverter:
         # The supervised cap on what may be written to THIS setpoint entity.
         # See the module docstring on why this is a number and not a `Tuning`.
         self.max_w = float(max_w)
+        # SAFETY-32. THIS PACK'S OWN BMS CUT-OUT, in percent, or None when the
+        # roster entry did not state one.
+        #
+        # ⚠️ NOT DEFAULTED HERE, AND None RATHER THAN A NUMBER. A cut-out is a
+        # property of the battery in the cupboard; inventing one for a pack that
+        # did not state it is precisely this card's defect - a pack graded
+        # against a floor that belongs to a different battery - rebuilt in the
+        # constructor. `peakguard.pack_floor_pct()` treats None as an unknown
+        # floor and `discharge_permitted()` treats an unknown floor as NO
+        # permission, so the absence costs a shave; validate.py rule 8 refuses
+        # the config by name long before that, at startup.
+        self.bms_soc_floor = (None if bms_soc_floor is None
+                              else float(bms_soc_floor))
 
         # --- the device's own reported range, read from its own entity -------
         # None until `hass.limits()` has answered. NOT guessed at: ESPHome is
@@ -189,7 +216,22 @@ class Inverter:
 
         # --- this unit's own measurements ------------------------------------
         self.soc = None
+        # ⚠️ SAFETY-37: `batt` IS NOW THE GATED READING, NOT THE RAW ONE. It is
+        # None whenever `batt_fresh` says the register is not following its own
+        # command - see freshness.py - and a None here is a MISSING input, which
+        # §11.1 rule 1 answers with 0 W. The raw number that arrived is on
+        # `batt_fresh.last`; read that only for diagnostics, never for control.
         self.batt = None
+        # SAFETY-37. One arrival record per SIGNAL per UNIT. Per unit for
+        # DEV-02's reason - a freshness verdict about B is not evidence about A,
+        # and at N>=2 a shared record would be the flat-scalar defect rebuilt
+        # inside the gate that exists to protect the per-unit checks.
+        #
+        # ⚠️ ONLY `batt` IS WIRED. `BOUNDS["soc"]` exists and is deliberately not
+        # constructed here: SoC's obligation term is energy through the pack, not
+        # command travel, and the constant it needs has not been measured. That
+        # is TEL-08's, and freshness.py's docstring says exactly what it owes.
+        self.batt_fresh = Freshness(BOUNDS["batt"])
 
         # --- what this unit was last told, and what it last accepted ---------
         # `target` is THIS unit's share of the site target from the last
@@ -242,6 +284,24 @@ class Inverter:
             self.store.set(self.key(name), value)
 
     # -- the numbers other modules ask this object for -----------------------
+    def standing_w(self) -> float:
+        """What this controller has standing on THIS unit's wire right now.
+
+        ⚠️ ONE DEFINITION, TWO CALLERS, and it was a transcription before
+        SAFETY-37. `cycle()` computes this for the sign watchdog and
+        `_read_unit()` needs the identical number for the freshness conjunction;
+        two spellings of "what is standing" would be two answers to the question
+        the gate and the check it protects are both asking, and the copy that
+        drifts is always the one further from the wire.
+
+        `last_write` is the value after the device clamp and confirmed accepted;
+        `target` covers the case where nothing has been written yet and,
+        deliberately, the case where the last write was REJECTED - the inverter
+        is then still latched on `last_write`, which is what `last_write` holds.
+        """
+        return float(self.last_write if self.last_write is not None
+                     else self.target)
+
     def rating_w(self) -> float:
         """The largest magnitude this unit can be commanded, in W.
 
@@ -295,6 +355,18 @@ class Inverter:
                                f"(limit {float(stale_s):.0f} s)")
         return True, ""
 
+    def stale_note(self) -> str:
+        """SAFETY-37's one line for the status page. Empty when nothing to say.
+
+        Separate from `link_note()` because they are about different halves of
+        the device and want opposite remedies: liveness is about the WRITE path
+        and its answer is to drop this unit and let the survivors carry it,
+        while a stale MEASUREMENT is about the read path and its answer is to
+        stop the site (`inputs_ok`). Folding one into the other is how a
+        measurement fault ends up handing a sibling extra power.
+        """
+        return self.batt_fresh.note(self.name)
+
     def link_note(self, now: datetime) -> str:
         """One line for the status page. Empty when there is nothing to say."""
         if not self.has_writer():
@@ -333,14 +405,46 @@ def roster_entries(opts: dict) -> list:
     return list(entries)
 
 
+def roster_names(opts: dict) -> list:
+    """The unit names, in roster order. THE one answer, for two callers.
+
+    ⚠️ IT EXISTS BECAUSE MQTT DISCOVERY CANNOT WAIT FOR A ROSTER. TEL-07 gives
+    every unit past the first its own MQTT device, and `MqttPublisher` is
+    constructed in `main()` BEFORE `Controller.__init__` builds the roster -
+    announcing happens on the broker's CONNACK, which can land first. Building a
+    second roster there would construct a second set of `Inverter`s off the same
+    Store; transcribing the naming rule there would be a third spelling of it.
+    So the naming rule lives here, `build_roster()` reads it, and the two cannot
+    drift.
+
+    ⚠️ THE FALLBACK NAME IS POSITIONAL, NOT `UNIT_A`. Two nameless entries both
+    called `inverter-a` would share one Store namespace, so one unit's SAFETY-02
+    latch would be the other's - a fault on B latching A is the exact failure
+    DEV-02's namespaced keys removed. Rule 9 refuses a nameless entry outright;
+    this only decides what the refusal is allowed to call it in the meantime.
+
+    An EMPTY `inverters:` is the flat-key shape and its one unit is `UNIT_A`,
+    which is what every install running today reads.
+    """
+    entries = roster_entries(opts)
+    if not entries:
+        return [UNIT_A]
+    names = []
+    for i, entry in enumerate(entries):
+        entry = entry if isinstance(entry, dict) else {}
+        names.append(str(entry.get("name") or "").strip() or f"inverter-{i + 1}")
+    return names
+
+
 def build_roster(opts: dict, store, sign_cfg=None) -> list:
     """The site's inverters, in roster order.
 
     TWO SHAPES, AND WHICH ONE IS IN FORCE IS DECIDED BY ONE TEST: is
     `inverters:` empty?
 
-      EMPTY   the five flat keys - `setpoint_entity`, `soc_entity`,
-              `batt_entity`, `batt_invert`, `max_w` - describe the ONE inverter,
+      EMPTY   the six flat keys - `setpoint_entity`, `soc_entity`,
+              `batt_entity`, `batt_invert`, `max_w`, `bms_soc_floor` (SAFETY-32)
+              - describe the ONE inverter,
               exactly as the shipped scalars did. This is what every install
               that upgrades into this version reads, without an operator
               touching anything, and it is byte-identical to what DEV-02
@@ -353,8 +457,8 @@ def build_roster(opts: dict, store, sign_cfg=None) -> list:
               `soc_entity` has no SoC sensor; it does NOT borrow the flat one,
               because "this unit's number came from somewhere else" is the
               defect DEV-02 spent a card removing and a fallback here would
-              rebuild it in three lines. `name`, `setpoint_entity` and `max_w`
-              are required of every entry - the schema enforces it on the
+              rebuild it in three lines. `name`, `setpoint_entity`, `max_w` and
+              `bms_soc_floor` (SAFETY-32) are required of every entry - the schema enforces it on the
               Supervisor path, `validate.py` rule 9 enforces it for sim/inject.py
               and the checks, which reach this function with any dict at all.
 
@@ -380,18 +484,24 @@ def build_roster(opts: dict, store, sign_cfg=None) -> list:
             batt_entity=opts.get("batt_entity", ""),
             batt_invert=bool(opts.get("batt_invert")),
             max_w=float(opts.get("max_w", 2000)),
+            # SAFETY-32. THE FLAT KEY, because this IS the single-inverter shape
+            # - the one pack the flat options describe is the one pack whose
+            # cut-out `bms_soc_floor` states. Defaulted from CFG-03's single
+            # mirror exactly as validate.py rule 8 defaults it, so an install
+            # that never set the key reads the same 10 % in both places.
+            bms_soc_floor=_flat_bms_floor(opts),
             store=store, sign_cfg=sign_cfg)]
 
     roster = []
-    for i, entry in enumerate(entries):
+    names = roster_names(opts)
+    # ⚠️ NAMES COME FROM `roster_names()`, NOT FROM A SECOND READING OF THE
+    # ENTRIES. TEL-07 announces one MQTT device and one `unique_id` per unit off
+    # these names, and it has to build them BEFORE a `Controller` exists - so a
+    # second spelling of the fallback here would be an entity announced under a
+    # name no unit answers to. `zip` pairs them positionally, which is what
+    # `roster_names()` is defined to be.
+    for entry, name in zip(entries, names):
         entry = entry if isinstance(entry, dict) else {}
-        # ⚠️ THE FALLBACK NAME IS POSITIONAL, NOT `UNIT_A`. Two nameless entries
-        # both called `inverter-a` would share one Store namespace, so one
-        # unit's SAFETY-02 latch would be the other's - a fault on B latching A
-        # is the exact failure DEV-02's namespaced keys removed. Rule 9 refuses
-        # a nameless entry outright; this only decides what the refusal is
-        # allowed to call it in the meantime.
-        name = str(entry.get("name") or "").strip() or f"inverter-{i + 1}"
         roster.append(Inverter(
             name,
             setpoint_entity=entry.get("setpoint_entity", ""),
@@ -401,10 +511,54 @@ def build_roster(opts: dict, store, sign_cfg=None) -> list:
             # ⚠️ NOT `opts["max_w"]`. See the docstring: a rating an entry did
             # not state is not the flat one, it is a rating rule 9 refuses.
             max_w=_entry_max_w(entry),
+            # ⚠️ NOT `opts["bms_soc_floor"]`, FOR `max_w`'S REASON AND THIS
+            # CARD'S. An entry that omits its cut-out has NOT got the flat one;
+            # it has none, and rule 8 refuses it by name. Borrowing here would be
+            # SAFETY-32's own defect written in three lines - the shallower pack
+            # graded against the deeper pack's BMS.
+            bms_soc_floor=_entry_bms_floor(entry),
             store=store, sign_cfg=sign_cfg))
     return roster
 
 
+def _flat_bms_floor(opts: dict):
+    """The single-inverter shape's own cut-out, or None if it is unparseable.
+
+    Defaulted from `PEAK_OPTION_DEFAULTS` when the key is absent or blank, which
+    is `validate._number()`'s behaviour on the same key - the two have to agree
+    or the validator would grade a number the roster does not build.
+    """
+    # ⚠️ ONE defaulting line, not two. The first cut wrote the fallback into the
+    # `.get()` AND into the blank test below it, and a mutation that deleted
+    # either one survived - each was covering for the other, which is
+    # MUTATION.md's masking section in three lines of configuration reading.
+    raw = opts.get("bms_soc_floor")
+    if raw is None or raw == "":
+        return float(PEAK_OPTION_DEFAULTS["bms_soc_floor"])
+    try:
+        return float(raw)
+    except (TypeError, ValueError):
+        return None
+
+
+def _entry_bms_floor(entry: dict):
+    """One entry's OWN cut-out, or None when it did not state a usable one.
+
+    None rather than a borrowed number and rather than 0.0 - `_entry_max_w()`
+    can answer 0.0 because a zero rating commands nothing, but a zero FLOOR is
+    the most permissive value the key has and would read as "this pack may be
+    emptied". Rule 8 refuses the missing key by name; until it does, None
+    withholds.
+    """
+    raw = entry.get("bms_soc_floor")
+    if raw is None or raw == "":
+        return None
+    try:
+        return float(raw)
+    except (TypeError, ValueError):
+        return None
+
+
 def _entry_max_w(entry: dict) -> float:
     """One entry's supervised cap, or 0.0 when it did not state a usable one.
 

goodwe_controller/app/main.py

@@ -45,6 +45,7 @@ from .circulation import (
 from .clamp import (
     REASON_CODE as CLAMP_REASON, ClampWatchdog, clamp_to_rating, is_commandable,
 )
+from . import freshness
 from .freeze import (
     FreezeWatchdog, FreezeWatchdogConfig, looks_frozen, rail_unreachable, rail_w,
 )
@@ -53,11 +54,12 @@ from .hass import HomeAssistant
 # and two checks read `app.main.LINK_STALE_S` to build a stale link, so the
 # window an operator would look up here is the one the roster actually uses.
 from .inverter import (LINK_STALE_S, UNIT_A, build_roster,
-                       roster_entries)
+                       roster_entries, roster_names)
 from .maintenance import (
     IDLE, POWER_MOVING, MaintConfig, Maintenance, arbitrate as maint_arbitrate,
 )
-from .mqtt import MqttPublisher
+from .mqtt import (MqttPublisher, announced_units, unit_slugs,
+                   unit_state_key)
 from . import peakguard
 from .p1 import P1Ingest, build_source, is_enabled
 from .price import Uncertainty, price_option
@@ -246,7 +248,13 @@ class Controller:
             # binds each unit's own share through its own `supervised` claim, so
             # nothing here can over-command a device.
             max_w=self.site_max_w,
-            slew_w=float(opts.get("slew_w", 1000)),
+            # ⚠️ SAFETY-39: THE FALLBACK IS 0 AND 0 MEANS "FOLLOW THE RAIL",
+            # which is what config.yaml ships and what `Tuning`'s own default
+            # is. It used to be 1000 - a third copy of a constant that had
+            # already gone stale against the rail in the other two - and rule
+            # 6's comment in validate.py documents what that costs when the
+            # copies disagree. `control.slew_limit_w()` is the one reader.
+            slew_w=float(opts.get("slew_w", 0) or 0),
             deadband_w=float(opts.get("deadband_w", 15)),
             target_grid_w=float(opts.get("target_grid_w", 0)),
             step_w=int(opts.get("step_w", 10)),
@@ -1065,6 +1073,26 @@ class Controller:
             return None
         return float(min(float(v) for v in vals))
 
+    @property
+    def packs(self) -> list:
+        """SAFETY-32. Each pack as its own THREE numbers, in roster order.
+
+        `pack_floor_soc` above is the site's ONE verdict and stays exactly what
+        DEV-02 made it - the emptiest measured pack. This is the thing that
+        reduction cannot produce: by the time `min()` has answered, WHICH pack
+        the number came from and how far that pack was from ITS OWN cut-out have
+        both been thrown away, and two packs at 15 % against cut-outs of 10 % and
+        20 % have opposite answers that are indistinguishable afterwards.
+
+        ⚠️ EVERY unit, live or not. Same reason as `inputs_ok`: a pack whose SoC
+        did not answer is a pack nothing can grade, and dropping it from this
+        list would let the site spend the packs that DID answer while one sat
+        unmeasured. `peakguard.discharge_permitted()` treats a None SoC as no
+        permission, which is where that must be decided.
+        """
+        return [peakguard.Pack(inv.name, inv.soc, inv.bms_soc_floor)
+                for inv in self.inverters]
+
     @property
     def inputs_ok(self) -> bool:
         """The site meter, and EVERY pack's own two readings.
@@ -1082,8 +1110,18 @@ class Controller:
                    for inv in self.inverters)
 
     # -- io ------------------------------------------------------------------
-    async def read_inputs(self) -> None:
+    async def read_inputs(self, now_mono: float | None = None) -> None:
+        """Every input this cycle needs, and SAFETY-37's freshness verdict.
+
+        `now_mono`  the monotonic clock the per-unit freshness records are
+                    stamped on. Defaulted rather than read inside `_read_unit()`
+                    so that ONE instant covers every unit in a gather - two
+                    units stamped from two clock reads would carry a freshness
+                    skew nobody could reproduce - and so that a check can drive
+                    real seconds through the gate without sleeping through them.
+        """
         o = self.o
+        now_mono = freshness.monotonic() if now_mono is None else float(now_mono)
         if self.p1_enabled:
             # ⚠️ P1 is the only authoritative measurement of what the utility
             # sees (§5.1). When it is stale this is None, which falls into the
@@ -1103,7 +1141,8 @@ class Controller:
         # names for the WRITE path, one function up. Within a unit the order is
         # unchanged (SoC, then battery power), so at the shipped roster of one
         # this is the same two calls in the same order.
-        await asyncio.gather(*(self._read_unit(inv) for inv in self.inverters))
+        await asyncio.gather(*(self._read_unit(inv, now_mono)
+                               for inv in self.inverters))
         if o.get("peak_forecast_entity"):
             raw = await self.hass.number(o["peak_forecast_entity"])
             # Accept kW or W - nobody's quarter-hour forecast is 50 W.
@@ -1149,10 +1188,41 @@ class Controller:
         elif self.inputs_bad_since is None:
             self.inputs_bad_since = datetime.now(timezone.utc)
 
-    async def _read_unit(self, inv) -> None:
-        """One inverter's own SoC and battery power, from ITS OWN entities."""
+    async def _read_unit(self, inv, now_mono: float) -> None:
+        """One inverter's own SoC and battery power, from ITS OWN entities.
+
+        ⚠️ SAFETY-37: THE POWER READING GOES THROUGH THE FRESHNESS GATE AND THE
+        SoC READING DOES NOT, AND THE ASYMMETRY IS DELIBERATE. `batt` feeds the
+        two consumers this card is about - SAFETY-30's per-unit sign check and
+        SAFETY-31's circulating-power sensor - and its obligation term is
+        command travel, which this method already has. SoC's obligation term is
+        ENERGY through the pack and the constant it needs has never been
+        measured on this site; wiring it here with a guessed constant would be a
+        gate that fires on a rested pack, which is TEL-08's whole hazard.
+        `freshness.BOUNDS["soc"]` states the bound and what TEL-08 owes.
+
+        ⚠️ THE STANDING COMMAND IS ASKED OF THE UNIT, NOT RECOMPUTED. `cycle()`
+        grades the sign watchdog against `inv.standing_w()` and this gate arms
+        off the same method, because the gate exists to protect that check and a
+        second spelling of "what is standing" would let the two disagree about
+        the number they are both reasoning about.
+        """
         inv.soc = await self.hass.number(inv.soc_entity)
-        inv.batt = await self.hass.number(inv.batt_entity, inv.batt_invert)
+        raw = await self.hass.number(inv.batt_entity, inv.batt_invert)
+        was_stale = inv.batt_fresh.stale
+        inv.batt_fresh.submit(raw, inv.standing_w(), now_mono)
+        # ⚠️ `inv.batt` IS THE GATED VALUE. A stale register is a MISSING input,
+        # not a measurement - `inputs_ok` sees the None, the site holds for
+        # `stale_input_s` and then commands 0 W and keeps commanding, which is
+        # §11.1 rule 1 and is already what a missing reading does here.
+        inv.batt = inv.batt_fresh.reading()
+        if inv.batt_fresh.stale and not was_stale:
+            self.log_event(f"STALE {inv.name}: " + inv.batt_fresh.reason)
+            _LOG.error("SAFETY-37: %s battery-power register is not following "
+                       "its own command - %s. Treating it as MISSING, which "
+                       "commands 0 W. It clears itself the moment the register "
+                       "reports a different value.",
+                       inv.name, inv.batt_fresh.reason)
 
     def write_refusal(self, value: float, inv=None) -> str | None:
         """Why `value` may NOT be written to `inv` right now, or None if it may.
@@ -1442,9 +1512,20 @@ class Controller:
         return tuple(live)
 
     def liveness_notes(self) -> list:
-        """Why each unit is or is not commandable, for the status page."""
+        """Why each unit is or is not commandable, for the status page.
+
+        ⚠️ SAFETY-37's STALE-READING LINE RIDES HERE TOO, AND IT IS A DIFFERENT
+        FAULT WITH A DIFFERENT REMEDY. A unit that is not commandable is dropped
+        and its share is carried by the survivors; a unit whose power register
+        has stopped following its command stops the SITE. They share this list
+        because they share one place on the status page - the operator asking
+        "why is nothing happening" needs both - and nothing downstream reads it.
+        """
         now = datetime.now(timezone.utc)
-        return [n for n in (inv.link_note(now) for inv in self.inverters) if n]
+        return [n for n in
+                [x for inv in self.inverters
+                 for x in (inv.link_note(now), inv.stale_note())]
+                if n]
 
     async def cycle(self) -> None:
         """Gather claims, resolve precedence, write the winner.
@@ -1533,7 +1614,10 @@ class Controller:
         standing = {}
         for inv in self.inverters:
             was_tripped = inv.sign_wd.tripped
-            stood = inv.last_write if inv.last_write is not None else inv.target
+            # ⚠️ `Inverter.standing_w()`, NOT THE EXPRESSION IT REPLACES.
+            # SAFETY-37's freshness gate arms off the same method, and this used
+            # to be the only spelling of it. See that method's docstring.
+            stood = inv.standing_w()
             standing[inv.name] = stood
             against = self.grid if n_units <= 1 else inv.batt
             if inv.sign_wd.evaluate(stood, against, self.following, now) \
@@ -1881,9 +1965,21 @@ class Controller:
             # protect. None stays None: `decide()` treats it as floor-limited,
             # which costs a shave rather than a pack.
             soc=self.pack_floor_soc,
-            soc_floor=float(self.o.get(
+            # ⚠️ SAFETY-32. THE SAME OPTION, REDUCED OVER THE PACKS' OWN
+            # CUT-OUTS. `peak_soc_floor` is still one site-wide EMS floor and is
+            # still read from that one key with CFG-03's one mirror behind it;
+            # what `binding_soc_floor()` adds is the conjunction with each pack's
+            # OWN `bms_soc_floor`, so the floor this site is graded against can
+            # never be below the deepest cut-out on the roster. MAXIMUM here
+            # pairs with the MINIMUM in `pack_floor_soc`: both reductions move
+            # the verdict towards refusing a shave and away from spending a pack.
+            # Under any config rule 8 accepts it IS the option, for every pack -
+            # asserted over the whole schema range in test_peakguard.py part 12
+            # rather than assumed, because "another rule refuses that" is a claim
+            # about rule ordering and sim/inject.py does not run rule 8 at all.
+            soc_floor=peakguard.binding_soc_floor(self.packs, float(self.o.get(
                 "peak_soc_floor",
-                peakguard.PEAK_OPTION_DEFAULTS["peak_soc_floor"])),
+                peakguard.PEAK_OPTION_DEFAULTS["peak_soc_floor"]))),
             max_hold_s=self.p1.averager.max_hold_s,
             # ⚠️ SAFETY-20. The device range goes in TOO, and this call site is
             # the one that needed it most: `standing` is `last_write`, i.e. the
@@ -2596,6 +2692,22 @@ class Controller:
         # notification that matters into a traceback.
         _at_floor = ("at the floor" if g.soc_floor is None
                      else f"at {float(g.soc_floor):.0f} %")
+        # ⚠️ SAFETY-32. WHICH PACK STOPPED THE SITE. `g.soc_floor` is the floor
+        # the decision was actually taken with, so this re-grades nothing and
+        # cannot disagree with the alarm it is printed inside. At a roster of one
+        # the sentence is omitted entirely and this notification is byte-for-byte
+        # what SAFETY-25 shipped - there is exactly one pack and naming it would
+        # be noise on every existing install.
+        _blocked = [name for name, why
+                    in peakguard.pack_permissions(self.packs, g.soc_floor)
+                    if why is not None]
+        _which = ("" if len(self.inverters) < 2 else
+                  f"\n\nSAFETY-32 - WHICH PACK: this is graded per pack against "
+                  f"that pack's own BMS cut-out (bms_soc_floor), and the "
+                  f"pack(s) at or below their own floor right now are "
+                  f"{', '.join(_blocked) if _blocked else '(none - see the reason above)'}"
+                  f". The other packs on the roster are not the reason the guard "
+                  f"stopped and raising their cut-out will not change this.")
         await self.hass.call("persistent_notification", "create", {
             "notification_id": "goodwe_peak_soc_floor",
             "title": "GoodWe: the capacity-peak guard has run out of battery",
@@ -2615,7 +2727,7 @@ class Controller:
                 f"{_at_floor} - ordinary self-consumption has no SoC "
                 f"floor at all and will go on discharging past it, down to the "
                 f"pack's own BMS cut-out. What has stopped is the guard buying "
-                f"you a lower bill, not the pack being spent."),
+                f"you a lower bill, not the pack being spent." + _which),
         })
 
     async def check_circulating(self) -> None:
@@ -3025,6 +3137,28 @@ class Controller:
         if self.p1_enabled:
             # Recomputed here, once a second, on purpose - see P1Ingest.
             values["p1_age"] = round(self.p1.published_age_s, 1)
+        # TEL-07. THE PER-UNIT ROWS, AND THE EMPTY LIST IS THE GATE.
+        #
+        # ⚠️ THERE IS NO `if len(self.inverters) > 1` HERE, DELIBERATELY.
+        # `announced_units()` answers `[]` at a roster of one, `zip` then yields
+        # nothing, and the values dict comes out byte-identical to what shipped -
+        # so the condition that decides what is ANNOUNCED is the same expression
+        # that decides what is PUBLISHED. Written as a second predicate, the two
+        # could disagree, and both directions are bad: an announced entity
+        # nothing feeds (the hazard `omit` exists for) or, at N=1, a published
+        # topic nothing announced, which AC 4 forbids outright.
+        #
+        # ⚠️ AND THE SITE ROWS ABOVE DO NOT MOVE. `battery` stays the SUM and
+        # `soc` stays the EMPTIEST pack; these are additions beside them, not a
+        # re-pointing of them, because those two ids are on the live install's
+        # dashboards and in its automations.
+        names = announced_units([inv.name for inv in self.inverters])
+        for inv, slug in zip(self.inverters, unit_slugs(names)):
+            values[unit_state_key(slug, "setpoint")] = inv.target
+            values[unit_state_key(slug, "battery")] = inv.batt
+            values[unit_state_key(slug, "soc")] = inv.soc
+            values[unit_state_key(slug, "sign_latch")] = (
+                "tripped" if inv.sign_wd.tripped else "clear")
         self.mqtt.publish(values)
 
     async def shutdown(self) -> None:
@@ -3731,6 +3865,13 @@ async def amain() -> None:
                 broker.get("username") if broker else None,
                 broker.get("password") if broker else None,
                 omit=() if is_enabled(opts) else ("p1_age",),
+                # TEL-07. ⚠️ THE NAMES, NOT A ROSTER. `build_roster()` here
+                # would construct a SECOND set of `Inverter`s off the same
+                # Store, minutes before `Controller.__init__` constructs the
+                # real ones; `roster_names()` is the naming rule on its own and
+                # is what `build_roster()` itself reads. At a roster of one this
+                # announces nothing new - see `announced_units()`.
+                units=roster_names(opts),
             )
         except Exception as err:  # noqa: BLE001
             _LOG.warning("MQTT unavailable (%s) - continuing without status entities", err)

goodwe_controller/app/mqtt.py

@@ -90,14 +90,239 @@ SENSORS = [
 BASE = "goodwe_ctl"
 AVAILABILITY = f"{BASE}/availability"
 
+# --- TEL-07: a SECOND device, for inverter B, and NOT one per inverter -------
+#
+# ⚠️ READ THE DEVICE-NAME NOTE ABOVE BEFORE CHANGING ANYTHING HERE. The device
+# name is half of every entity_id, so re-scoping `DEVICE` renames every entity
+# the live install already has - and HA keeps the id it composed at FIRST
+# discovery, so what a rename actually produces is a NEW entity beside a dead
+# one: the history stays behind on the old id, and every dashboard, template
+# and automation that names it (including `goodwe_master_watchdog_held_*` and
+# `goodwe_master_parked_at_0_w_*`) keeps pointing at the entity that stopped
+# updating. That is silent. So:
+#
+#   `DEVICE` IS NOT TOUCHED AND ITS ENTITIES ARE NOT TOUCHED. It is the SITE
+#   device - the meter's view and the controller's own state - and at the
+#   shipped roster of one it is also, in effect, inverter A's.
+#
+#   THE FIRST ROSTER ENTRY GETS NO NEW DEVICE. Its per-unit rows are announced
+#   ON THE DEVICE IT ALREADY HAS, under new `unique_id`s and new names. Nothing
+#   existing is renamed, so nothing existing loses its history.
+#
+#   EVERY LATER ENTRY GETS ITS OWN DEVICE (`via_device` the site one).
+#
+# ⚠️ THE ASYMMETRY IS THE POINT, AND IT WILL LOOK LIKE AN OVERSIGHT. "One
+# device per inverter", with A as `inverter-a` and B as `inverter-b`, is tidy,
+# symmetrical, and is the change that destroys the live system's recorded
+# history. DO NOT "CLEAN THIS UP". The composed entity_ids come out symmetric
+# anyway - `sensor.goodwe_inverter_a_battery_power` and
+# `sensor.goodwe_inverter_b_battery_power` - which is the whole benefit of the
+# tidy version, without the cost.
+#
+# WHAT IS PER-UNIT AND WHAT IS SITE, and why the split is where it is:
+#
+#   PER-UNIT   setpoint (this unit's share of the site target, the number its
+#              own heartbeat re-emits), battery power (`inv.batt`, this unit's
+#              own meter reading), SoC (`inv.soc`, THIS pack - the site row is
+#              the EMPTIEST pack, which at N>=2 may be the other one), and the
+#              SAFETY-02 sign latch, which is per actuator by construction.
+#
+#   SITE       `grid` and `p1_age`. There is ONE P1 meter and ONE grid
+#              connection; announcing them per inverter would invent two of a
+#              thing there is one of. `p1_sample_age_s` is additionally a
+#              WATCHDOG INPUT (see `omit` below and the firmware note above), so
+#              a second copy of it is a second copy of a safety signal - two
+#              answers to "is the meter fresh?", one of which is always the one
+#              nobody is looking at. Also site: circulating power (it is
+#              `sum(|Bi|) - |sum(Bi)|`, a property of the SET), the controller
+#              status, the maintenance phase, and the capacity-tariff peak.
+#
+#   NOT ANNOUNCED, AND SAID OUT LOUD RATHER THAN LEFT LOOKING FINISHED: the
+#   card also lists "inverter AC power" and per-unit HEARTBEATS as per-unit.
+#   Neither has a source in this add-on today - nothing reads an AC-power
+#   register per unit, and `inv.last_beat` is a monotonic loop clock with no
+#   wall-clock age published anywhere. Announcing them would create entities
+#   nothing ever feeds, which is exactly what the `omit` note below refuses to
+#   do for `p1_sample_age_s`. They are gaps, not omissions.
+UNIT_SENSORS = [
+    ("setpoint", "setpoint", "Setpoint", "W", "power", "measurement", None),
+    ("battery", "battery_power", "Battery power", "W", "power", "measurement", None),
+    ("soc", "battery_soc", "Battery SoC", "%", "battery", "measurement", None),
+    ("sign_latch", "sign_latch", "Sign latch", None, None, None, "mdi:flash-alert"),
+]
+
+# ⚠️ A ROSTER OF ONE ANNOUNCES NOTHING NEW - not a device, not an entity, not a
+# topic. Every install running today is a roster of one, and "the upgrade added
+# four entities nobody asked for" is a change to a live system's entity list
+# for no information: at N=1 the site rows ARE this unit's rows, exactly.
+PER_UNIT_MIN_ROSTER = 2
+
+
+def _slug(text) -> str:
+    """Home Assistant's own object_id spelling: lowercase, `_`, no runs.
+
+    ⚠️ ASCII-ONLY ON PURPOSE. `str.isalnum()` is true for 'é' and for '٤', and
+    HA transliterates those rather than keeping them, so treating them as
+    alphanumeric here would produce an id this module claims and HA does not.
+    They become separators, which is conservative in the right direction: two
+    names that differ ONLY outside ASCII collide, and `unit_slugs()` below is
+    what stops a collision becoming two entities with one `unique_id`.
+    """
+    out = []
+    for ch in str(text).strip().lower():
+        out.append(ch if (ch.isascii() and ch.isalnum()) else "_")
+    slug = "".join(out)
+    while "__" in slug:
+        slug = slug.replace("__", "_")
+    return slug.strip("_")
+
+
+def _title(name) -> str:
+    """`inverter-b` -> `Inverter B`. The half of the entity_id HA composes."""
+    words = str(name).replace("-", " ").replace("_", " ").split()
+    return " ".join(w[:1].upper() + w[1:] for w in words) or str(name)
+
+
+def unit_slugs(units) -> list:
+    """One id-safe slug per roster entry, in roster order, ALL DISTINCT.
+
+    ⚠️ THE DE-COLLISION IS NOT DECORATION. `validate.py` rule 9(c) refuses two
+    entries with the SAME name; it does not refuse `inverter-b` beside
+    `Inverter B`, and those two slug to one string. Two entities published with
+    one `unique_id` is not an error in HA - the second one is DROPPED, so one
+    inverter's telemetry silently stops existing. The suffix is the roster
+    INDEX, so it is stable for a given roster and does not depend on what the
+    other unit is called.
+    """
+    slugs, seen = [], set()
+    for i, name in enumerate(units):
+        slug = _slug(name) or f"inverter_{i + 1}"
+        while slug in seen:
+            slug = f"{slug}_{i + 1}"
+        seen.add(slug)
+        slugs.append(slug)
+    return slugs
+
+
+def announced_units(units) -> list:
+    """The roster, in order - or EMPTY below `PER_UNIT_MIN_ROSTER`.
+
+    ⚠️ ONE ANSWER TO "WHICH UNITS GET PER-UNIT ENTITIES", read by the
+    announcement here AND by `Controller.publish()` in main.py. Two spellings of
+    the same predicate is how an entity gets announced that nothing publishes
+    to, or published to on a topic nothing announced - and at N=1 the second
+    would be an added topic, which AC 4 forbids outright.
+    """
+    names = [str(u) for u in units]
+    if len(names) < PER_UNIT_MIN_ROSTER:
+        return []
+    return names
+
+
+def unit_state_key(slug: str, key: str) -> str:
+    """The `publish()` key - i.e. the state topic under `BASE` - for one unit.
+
+    Written once, here, because main.py builds it and this module announces it;
+    a second transcription is a topic announced and never fed.
+    """
+    return f"unit/{slug}/{key}"
+
+
+def unit_device(name, slug: str) -> dict:
+    """B's OWN device. ⚠️ Never returned for the first roster entry."""
+    return {
+        "identifiers": [f"{DEVICE['identifiers'][0]}_{slug}"],
+        "name": f"{DEVICE['name']} {_title(name)}",
+        "manufacturer": DEVICE["manufacturer"],
+        "model": DEVICE["model"],
+        # Hangs B under the controller in HA's device tree rather than beside
+        # it. Cosmetic, and the one line that says in the UI what the asymmetry
+        # above means: there is one controller, and it drives both.
+        "via_device": DEVICE["identifiers"][0],
+    }
+
+
+def _payload(name, object_id, unique_id, state_topic, device,
+             unit, dev_class, state_class, icon) -> dict:
+    """One discovery payload.
+
+    ⚠️ KEY ORDER IS PART OF THE OUTPUT. `json.dumps` writes keys in insertion
+    order, so this dict's construction order IS the bytes on the wire, and AC 1
+    is a BYTE comparison against what `release/1.0` publishes. Do not reorder.
+    """
+    cfg = {
+        "name": name,
+        "object_id": object_id,
+        "unique_id": unique_id,
+        "state_topic": state_topic,
+        "availability_topic": AVAILABILITY,
+        "device": device,
+    }
+    if unit:
+        cfg["unit_of_measurement"] = unit
+    if dev_class:
+        cfg["device_class"] = dev_class
+    if state_class:
+        cfg["state_class"] = state_class
+    if icon:
+        cfg["icon"] = icon
+    return cfg
+
+
+def discovery_payloads(units=(), omit=()) -> list:
+    """Every `(topic, payload)` this add-on announces, in announcement order.
+
+    Split out of `_announce()` so that the acceptance criterion can be graded as
+    a DIFF OF THE ANNOUNCED PAYLOADS against `release/1.0`, rather than as a
+    reading of the code. `_announce()` publishes exactly this list and nothing
+    else, which is itself checked.
+    """
+    omit = set(omit)
+    out = []
+    for key, object_id, name, unit, dev_class, state_class, icon in SENSORS:
+        if key in omit:
+            continue
+        out.append((
+            f"homeassistant/sensor/{BASE}_{key}/config",
+            _payload(name, object_id, f"{BASE}_{key}", f"{BASE}/{key}",
+                     DEVICE, unit, dev_class, state_class, icon)))
+    names = announced_units(units)
+    slugs = unit_slugs(names)
+    site_slug = _slug(DEVICE["name"])
+    for i, (name, slug) in enumerate(zip(names, slugs)):
+        # ⚠️ `i == 0` IS THE ASYMMETRY, IN ONE LINE. The first roster entry
+        # keeps the device it already has and carries its name in the ENTITY
+        # name instead; every later one gets its own device and does not.
+        # Either way HA composes device-name + entity-name into the same
+        # string, which is why `object_id` below can be written once for both.
+        device = DEVICE if i == 0 else unit_device(name, slug)
+        prefix = f"{_title(name)} " if i == 0 else ""
+        for key, oid, label, unit, dev_class, state_class, icon in UNIT_SENSORS:
+            unique_id = f"{BASE}_unit_{slug}_{key}"
+            out.append((
+                f"homeassistant/sensor/{unique_id}/config",
+                _payload(prefix + label,
+                         f"{site_slug}_{slug}_{oid}",
+                         unique_id,
+                         f"{BASE}/{unit_state_key(slug, key)}",
+                         device, unit, dev_class, state_class, icon)))
+    return out
+
 
 class MqttPublisher:
-    def __init__(self, host, port, username=None, password=None, omit=()):
+    def __init__(self, host, port, username=None, password=None, omit=(),
+                 units=()):
         # `omit` drops sensor keys from discovery entirely. ⚠️ Announcing a
         # sensor that nothing will ever publish to is not harmless here:
         # p1_sample_age_s is a watchdog input, and an entity that exists but is
         # never fed is a worse signal than one that does not exist at all.
         self.omit = set(omit)
+        # TEL-07. The roster's NAMES, in roster order - `inverter.roster_names()`,
+        # not a second reading of the option. Defaults to empty, which
+        # `announced_units()` treats exactly as a roster of one: nothing
+        # per-unit is announced, so every caller that has not been taught about
+        # the roster keeps publishing what it published before.
+        self.units = [str(u) for u in units]
         self.enabled = mqtt is not None and bool(host)
         self.client = None
         if not self.enabled:
@@ -130,29 +355,12 @@ class MqttPublisher:
             self.enabled = False
 
     def _announce(self) -> None:
-        for key, object_id, name, unit, dev_class, state_class, icon in SENSORS:
-            if key in self.omit:
-                continue
-            cfg = {
-                "name": name,
-                "object_id": object_id,
-                "unique_id": f"{BASE}_{key}",
-                "state_topic": f"{BASE}/{key}",
-                "availability_topic": AVAILABILITY,
-                "device": DEVICE,
-            }
-            if unit:
-                cfg["unit_of_measurement"] = unit
-            if dev_class:
-                cfg["device_class"] = dev_class
-            if state_class:
-                cfg["state_class"] = state_class
-            if icon:
-                cfg["icon"] = icon
-            self.client.publish(
-                f"homeassistant/sensor/{BASE}_{key}/config",
-                json.dumps(cfg), retain=True,
-            )
+        # ⚠️ NO PAYLOAD IS BUILT HERE. `discovery_payloads()` is the whole
+        # announcement, so the check that diffs it against `release/1.0` is
+        # diffing what actually goes on the wire - and a payload built here
+        # instead would be one this add-on publishes and no check has ever seen.
+        for topic, cfg in discovery_payloads(self.units, self.omit):
+            self.client.publish(topic, json.dumps(cfg), retain=True)
         self.client.publish(AVAILABILITY, "online", retain=True)
 
     def publish(self, values: dict) -> None:

goodwe_controller/app/peakguard.py

@@ -360,6 +360,29 @@ distinction in DOCS.md and in this comment. Revisit if a THIRD floor appears -
 a loop-side guard would be the third - at which point the migration buys enough
 to be worth its cost.
 
+------------------------------------------------------------------------------
+SAFETY-32: ONE `bms_soc_floor` FOR TWO PACKS GRADES ONE AGAINST THE OTHER'S BMS
+
+`bms_soc_floor` above describes A PACK, not a site, and it was a flat option
+because there was one pack. At two, two batteries of different models have
+different cut-outs, and one number for both is wrong in the direction that
+empties a battery: the SHALLOWER pack (the higher cut-out) is protected by a
+floor that belongs to the DEEPER one. So it became a roster key - `Pack` carries
+each unit's own value, `pack_floor_pct()` conjoins it with the site's EMS floor,
+and validate.py rule 8 grades EVERY unit and NAMES the one it refuses.
+
+⚠️ `peak_soc_floor` DID NOT MOVE, AND THE RESIDUAL IS RECORDED RATHER THAN
+HIDDEN. It is one number for the site, so with cut-outs of 10 % and 18 % the
+operator must set it above 18 and the deeper pack is then withheld above its own
+need. That half - a per-pack EMS floor - is NOT this card and must not be
+smuggled in with it; DECISIONS/SAFETY-32-per-pack-bms-floor.md states it as the
+open question it is.
+
+⚠️ AND THE MIN() OVER MEASURED SoC IS STILL RIGHT. `Controller.pack_floor_soc`
+reduces to the emptiest pack and this card does not touch it. What changed is
+the FLOOR it is graded against, and the addition of a per-pack answer beside the
+site's one verdict - see `pack_permissions()`.
+
 ------------------------------------------------------------------------------
 AND IT READS NO PER-PHASE QUANTITY, ON PURPOSE
 
@@ -572,6 +595,110 @@ def discharge_permitted(soc, soc_floor) -> str | None:
     return None
 
 
+@dataclass(frozen=True)
+class Pack:
+    """SAFETY-32. ONE pack's three numbers for the floor question, NAMED.
+
+    `name`       the roster name, because a refusal that does not say WHICH pack
+                 stopped the site sends an operator to the wrong device - the
+                 same defect CFG-04's `unit_caps_indexed()` was written for.
+    `soc`        THIS pack's measured state of charge. None when its sensor did
+                 not answer, and None is not a full battery.
+    `bms_floor`  THIS pack's OWN cut-out percent (`bms_soc_floor`), which is a
+                 property of the hardware in the cupboard and NOT of the site.
+                 None when the roster entry did not state one - see
+                 `pack_floor_pct()` for why that is withheld and not 0 %.
+
+    ⚠️ IT CARRIES THE CUT-OUT, NOT THE EMS FLOOR. `peak_soc_floor` is one number
+    for the whole site (the depth a money-saving discharge may never reach) and
+    stays a flat option; `bms_soc_floor` describes a battery and became a roster
+    key here, because two packs of different models have different cut-outs and
+    grading both against one of them is wrong in the direction that empties the
+    shallower one.
+    """
+
+    name: str
+    soc: float | None
+    bms_floor: float | None
+
+
+def pack_floor_pct(pack, soc_floor):
+    """The percent THIS pack may not be spent below, or None if that is unknown.
+
+    `max(the site's EMS floor, this pack's own cut-out)` - the CONJUNCTION, and
+    the direction matters: the EMS floor is what the operator asked for and the
+    cut-out is what the hardware will do anyway, so a pack is protected by
+    whichever is higher. Taking the site floor alone is the shipped defect this
+    card removes (the shallower pack graded against the deeper one's cut-out);
+    taking the cut-out alone would throw SAFETY-24's margin away.
+
+    ⚠️ AN UNSTATED CUT-OUT IS None, NOT ZERO, AND NOT THE FLAT OPTION. 0 % would
+    be a floor that permits everything - the most permissive value there is,
+    invented from an absence - and borrowing the flat `bms_soc_floor` is CFG-04's
+    "nothing is inherited" broken in one line, which is this card's whole subject
+    restated. `discharge_permitted()` already treats a None floor as NO
+    permission, so an entry that forgot the key costs a shave rather than a pack.
+
+    ⚠️ AND UNDER A rule-8-VALID CONFIG THIS IS `soc_floor`, FOR EVERY PACK.
+    validate.py rule 8 refuses `peak_soc_floor <= bms_soc_floor` on EVERY unit,
+    so `max()` selects the EMS floor everywhere the add-on will actually start -
+    which is exactly why the reduction is written here rather than assumed at the
+    call site. "Another rule refuses that config" is a claim about today's rule
+    ordering, not a property of this function, and `validate_startup_config()` is
+    also `sim/inject.py`'s entry point. `unit_caps_indexed()`'s docstring records
+    the same argument, and CFG-04's index desynchronisation is what happened the
+    last time it was left implicit.
+    """
+    if soc_floor is None or pack.bms_floor is None:
+        return None
+    return max(float(soc_floor), float(pack.bms_floor))
+
+
+def pack_permissions(packs, soc_floor) -> list[tuple[str, str | None]]:
+    """SAFETY-32. Per pack: None if it may be spent, else the reason it may not.
+
+    ONE `(name, reason)` pair per pack, in roster order, from the SAME
+    `discharge_permitted()` the site verdict uses - a second transcription of
+    "may this pack be spent" is a second answer to it, which is the argument
+    that made that predicate public in the first place.
+
+    ⚠️ THIS IS THE OBSERVABLE THE MIN() CANNOT PRODUCE. `Controller.pack_floor_soc`
+    reduces the measured SoC to the emptiest pack BEFORE anything is graded, and
+    that reduction is right for the site's one verdict - but it has thrown away
+    which pack it came from and how far that pack was from ITS OWN floor by the
+    time the answer exists. Two packs at 15 % against floors of 10 % and 20 %
+    have opposite answers and are indistinguishable after the `min()`.
+    """
+    return [(p.name, discharge_permitted(p.soc, pack_floor_pct(p, soc_floor)))
+            for p in packs]
+
+
+def binding_soc_floor(packs, soc_floor):
+    """The ONE floor `decide()` may grade `pack_floor_soc` against, at a roster.
+
+    MAXIMUM over the packs' own floors, and it is the conservative reduction that
+    pairs with the MINIMUM `pack_floor_soc` reduction: `min(soc) <= max(floor)`
+    is implied by "some pack is at or below its own floor", so this verdict is
+    never more permissive than grading each pack separately would be. The other
+    direction is not true and is not claimed - a site can be refused here while
+    every pack individually has headroom, which costs a shave and never a pack.
+
+    None when ANY pack's floor is unknown, for `Controller.site_dev_bound()`'s
+    reason and in the same direction: `discharge_permitted()` treats a None floor
+    as no permission, so an unknown floor withholds rather than defaults.
+
+    ⚠️ AT N=1 THIS IS `soc_floor` ITSELF under any config rule 8 accepts, and
+    test_peakguard.py part 12 asserts that over the whole schema range rather
+    than assuming it.
+    """
+    if not packs:
+        return None if soc_floor is None else float(soc_floor)
+    floors = [pack_floor_pct(p, soc_floor) for p in packs]
+    if any(f is None for f in floors):
+        return None
+    return max(floors)
+
+
 def decide(projection, *, batt_w, cap_w, reading, achievable_w, soc, soc_floor,
            max_hold_s=None, frozen: bool = False) -> PeakDecision:
     """The whole guard. Pure: no clock, no I/O, no state carried between calls.

goodwe_controller/app/validate.py

@@ -132,7 +132,7 @@ NOT READY banner already names the problem, (b) does not apply.
      installed base is on a fixed or static tariff. Refusing to start without a
      price feed would lock those sites out of the add-on entirely.
 
-  8. `peak_soc_floor` at or below `bms_soc_floor`.  [(a)]
+  8. `peak_soc_floor` at or below `bms_soc_floor`, ON ANY UNIT.  [(a)]
      SAFETY-24, and the same shape as 1, 4, 5 and 6. The peak guard can COMMAND
      a discharge to hold a billed quarter down (SAFETY-07), and `peak_soc_floor`
      is the EMS-side bound on how far down it may take the pack. The BMS has its
@@ -142,6 +142,12 @@ NOT READY banner already names the problem, (b) does not apply.
      of binding while its status page reports one - rule 5's "a disarmed guard
      that advertises itself as armed", on the guard whose failure mode is a pack
      that is quietly never available when it is wanted.
+     ⚠️ SAFETY-32: `bms_soc_floor` DESCRIBES A BATTERY, so at a roster it is a
+     per-entry key and this rule grades EVERY unit and NAMES the one it refuses.
+     One number for two packs of different models refuses the wrong config and
+     accepts the wrong one - cut-outs of 10 % and 30 % under `peak_soc_floor: 20`
+     used to start. A missing per-entry cut-out is refused here rather than
+     defaulted: a cut-out invented for a pack IS this defect.
 
      ⚠️ `<=`, NOT `<`, and the equality case is the interesting one. At exactly
      equal, the EMS floor and the pack's cut-out act at the same percent, so the
@@ -177,6 +183,60 @@ NOT READY banner already names the problem, (b) does not apply.
      the per-unit form and main.py runs it from `run_control()`, once every
      unit's own ESPHome has replied.
 
+ 10. `slew_w` above the fraction of the SITE RAIL the plant can follow.  [(a)]
+     SAFETY-39, and the first rule here whose subject is a RELATIONSHIP rather
+     than a threshold. `slew_w` bounds how far the site command may move in one
+     cycle; `control.SLEW_RAIL_FRAC` is `LOOP_TICK_S / PLANT_SETTLE_S`, so
+     `SLEW_RAIL_FRAC * rail` is the largest step at which the loop still takes
+     the plant's own measured settling time to traverse its whole output range.
+     Above it the controller commands its entire range before it can observe
+     its answer to the first step, and the stated limit - "the command moves at
+     most `slew_w` per cycle, so it cannot jump ahead of the inverter" - is
+     untrue: it jumps ahead by construction.
+
+     ⚠️ THIS IS (a) AND NOT (b), and the distinction is what makes it a refusal
+     rather than a warning. Nothing goes inert. What happens is that a bound
+     the operator set means something other than what it says, and the layer
+     that overrules it is the PLANT - which has no status row, publishes
+     nothing, and cannot be read off any page in this add-on. Measured on the
+     owner's system 2026-09-05 11:43-11:46 at `max_w: 5000`, `slew_w: 1000`:
+     setpoint 380 -> 5000 in five 2 s ticks, battery -5154 W against a 5000 VA
+     inverter, and the grid driven from 3.4 kW of EXPORT to 2.8 kW of IMPORT.
+     Large (>= 900 W) setpoint steps per 30 min climbed 2 -> 1 -> 13 -> 43 that
+     morning. Nothing in the add-on reported anything wrong, because nothing
+     was: the loop followed its command exactly, and the command was wrong.
+
+     ⚠️ IT IS GRADED AGAINST THE ROSTER SUM, NOT THE FLAT `max_w` AND NOT THE
+     WEAKEST UNIT, and this is the one rule in this file for which that is the
+     right rail. Rules 5, 6 and 8 are all about ONE unit - one watchdog, one
+     shaping claim, one pack - so they take `min()` over `unit_caps()`.
+     `slew_w` is not per unit: `main.py` builds `Tuning(max_w=self.site_max_w)`
+     and `compute()` produces the SITE target, which the allocator then splits.
+     So the range this bound is about is the sum, `Controller.site_max_w`, and
+     `site_rail_w()` below is that same number computed from options.
+
+     ⚠️ AND THE `site_sign_disagree_w` NOTE IN config.yaml IS NOT A PRECEDENT
+     AGAINST THIS. That note says there is deliberately no rule pairing
+     `site_sign_disagree_w` with `max_w`, "because the bound on the SITE command
+     is `Controller.site_max_w`, the ROSTER SUM, and `validate_startup_config()`
+     is handed options rather than a roster. A rule written against max_w would
+     refuse a perfectly reachable two-inverter configuration." That objection is
+     to grading a site quantity against the FLAT key. It is answered rather than
+     ignored: `unit_caps()` already reads the roster the add-on will build, so
+     the roster sum IS available here, and this rule takes it.
+
+     ⚠️ THE DIRECTION OF THIS RULE, SAID PLAINLY, BECAUSE IT IS NOT THE
+     DIRECTION THE TICKET ASSUMED. A rail that GROWS loosens this bound: at a
+     9600 W two-inverter rail, `slew_w: 1000` traverses the rail in 19.2 s and
+     passes, while at 5000 W the same 1000 W is the configuration measured
+     above. That is what the constraint says and it is correct - the bound is on
+     traverse TIME, and a bigger rail at the same step size takes longer to
+     cross. What this rule therefore protects against is the constant being left
+     behind when the rail moves EITHER way. It is NOT a bound on how much power
+     the site may command, and it does NOT bound the over-absorption: see the
+     note below on `gain`, which is the term that owns that and which SAFETY-39
+     measured and did not change.
+
 WHAT IS DELIBERATELY *NOT* REFUSED, because it is untidy rather than unsafe:
 
   - `integrator_max_w` above `max_w`. DOCS.md is right that the only thing the
@@ -220,6 +280,34 @@ WHAT IS DELIBERATELY *NOT* REFUSED, because it is untidy rather than unsafe:
     is answered. Compare rule 5, which CAN be settled at startup because both
     `sign_disagree_w` and `max_w` are config and are both known at boot.
 
+  - `gain` at any value the schema accepts, INCLUDING against a large rail.
+    SAFETY-39 measured this and deliberately left it alone, which is worth more
+    than the rule would have been. On admin/goodwe's rig, over a family of 51
+    export steps from 1.0 to 4.2 kW at `max_w: 5000` and a 2 s tick, the
+    over-absorption - peak battery power beyond what the site actually needed -
+    is FLAT in `slew_w`: 958 W at slew 1000 and 1081 W at slew 250. It falls
+    in `gain`: 987 W at 0.6, 876 W at 0.3, 435 W at 0.2 - a real reduction, but
+    NOT to zero, and the 0.2 figure is the one worth not rounding away. The
+    reason is structural and is visible in control.py: `slew_w` bounds the
+    OUTPUT, while the integrator accumulates `gain * error` per cycle and is
+    bounded only by `integrator_max_w`. At gain 0.6 into a 3.4 kW error the
+    integrator moves ~2040 W per tick and reaches a 5000 W rail in under three
+    ticks whatever `slew_w` is.
+    So the 2026-08-22 derivation's own sentence - "the gain, not the slew, is
+    the limit by then" - is now literally true, and `gain` is the constant that
+    needs re-deriving next. It is NOT refused and NOT changed here: it is a
+    live control-law constant on a running house, changing it in the same pull
+    request as `slew_w` would make the next measurement uninterpretable, and a
+    validator rule pairing `gain` with a rail would be inventing a relationship
+    nobody has measured. Named here so it is a known open item rather than an
+    omission. See DECISIONS/SAFETY-39-slew-against-the-rail.md.
+
+  - `slew_w` BELOW the rail fraction, at any value the schema accepts. Slower
+    than the plant is always safe and is sometimes necessary - the live install
+    has run an explicit 400 W against a 5000 W rail since 2026-09-05 12:00,
+    which is 12.5 ticks to traverse the rail against the 9 this rule requires.
+    Refusing "too slow" would refuse the mitigation that is holding.
+
   - `peak_soc_floor` below `maintenance_soc_floor`, or above it. They are
     DIFFERENT QUANTITIES (SAFETY-24: a drain target versus a spend limit) and
     every ordering of the two is a legitimate site configuration. Refusing on
@@ -229,6 +317,7 @@ WHAT IS DELIBERATELY *NOT* REFUSED, because it is untidy rather than unsafe:
 import logging
 
 from .arbitrage import enabled as arbitrage_on
+from .control import SLEW_RAIL_FRAC, LOOP_TICK_S, PLANT_SETTLE_S
 from .inverter import roster_entries
 from .maintenance import MAINT_OPTION_DEFAULTS
 from .p1 import is_enabled, validate_meter_options
@@ -386,6 +475,70 @@ def unit_caps_indexed(opts: dict) -> list[tuple[int, float]]:
     return caps
 
 
+def site_rail_w(opts: dict) -> float | None:
+    """The SITE rail: what the whole site may be commanded, in W. Rule 10's rail.
+
+    ⚠️ THE SUM, NOT THE MINIMUM, AND NOT THE FLAT KEY - and it is the only place
+    in this file that wants a sum. Rules 5, 6 and 8 grade a threshold against
+    ONE unit (one watchdog, one shaping claim, one pack) and take `min()` over
+    `unit_caps()`. `slew_w` is not a per-unit quantity at all: `main.py` builds
+    `Tuning(max_w=self.site_max_w)` from the roster sum and `compute()` emits
+    the SITE target, which the allocator then divides. So the output range
+    `slew_w` is a rate across is `Controller.site_max_w`, and this is that same
+    number read out of options rather than off a built roster.
+
+    At the shipped roster of one this is `unit_caps()`'s single entry, which is
+    `max_w` exactly - byte for byte the number the single-inverter shape has
+    always meant. None when no entry carries a usable cap, which rule 9 has
+    already refused by the time rule 10 runs.
+    """
+    caps = unit_caps(opts)
+    return float(sum(caps)) if caps else None
+
+
+def unit_bms_floors_indexed(opts: dict) -> list[tuple[int, object, object]]:
+    """SAFETY-32. Each pack's OWN `bms_soc_floor`, carrying its ROSTER INDEX.
+
+    `(roster index, the raw value as configured, the parsed float or None)`, one
+    triple per unit. The raw value travels too because the refusal quotes what
+    the operator actually wrote, and `!r` of a re-read `opts` key is the wrong
+    string the moment the value came off a roster entry.
+
+    ⚠️ THE INDEX IS THE ROSTER'S, NOT THIS LIST'S, AND THAT IS CFG-04'S BUG
+    WRITTEN DOWN. Rules 5 and 6 fed a CAPS-list index into `_unit_label()`,
+    which indexes the ROSTER, so on a roster whose first entry was malformed the
+    refusal named the WRONG INVERTER - an operator sent to the wrong device by
+    the very message that exists to stop that. `unit_caps_indexed()` exists
+    because of it. This function goes one step further and SKIPS NOTHING: every
+    entry produces a triple, including the ones with no usable floor, because a
+    missing cut-out is itself what rule 8 has to refuse BY NAME. There is
+    therefore no second list for an index to desynchronise from.
+
+    ⚠️ AND NOTHING IS INHERITED. At a declared roster the FLAT `bms_soc_floor` is
+    not read at all - CFG-04's rule, and this card's subject: a pack that borrows
+    a sibling's cut-out is graded against a battery it is not. At the flat shape
+    the flat key IS this one pack's cut-out, defaulted from CFG-03's single
+    mirror exactly as `inverter._flat_bms_floor()` defaults it.
+    """
+    entries = roster_entries(opts)
+    if not entries:
+        return [(0, opts.get("bms_soc_floor"),
+                 _number(opts, "bms_soc_floor",
+                         PEAK_OPTION_DEFAULTS["bms_soc_floor"]))]
+    out: list[tuple[int, object, object]] = []
+    for index, entry in enumerate(entries):
+        if not isinstance(entry, dict):
+            # Rule 9(a)/(b) already refuses a non-dict entry by index, and it
+            # runs FIRST. Naming it twice would hand the operator two sentences
+            # about one line of YAML.
+            continue
+        raw = entry.get("bms_soc_floor")
+        out.append((index, raw,
+                    None if raw is None or raw == ""
+                    else _number(entry, "bms_soc_floor", None)))
+    return out
+
+
 def _unit_label(opts: dict, index: int) -> str:
     """"" at a single-inverter config, " (inverter-b)" at a roster.
 
@@ -757,21 +910,48 @@ def validate_startup_config(opts: dict, dev_min=None, dev_max=None) -> list[str]
     # second inverter is added - which is the day nobody is watching the startup
     # log. This is `meter_max_age_s`'s rule read the same way: the failure it
     # prevents is silent.
+    #
+    # ⚠️ AND IT READS THE WEAKEST UNIT'S CAP, NOT THE FLAT `max_w` - SAFETY-32
+    # ROUND 5. This branch used to compare against `max_w = _number(opts,
+    # "max_w", 2000.0)`, the FLAT option, which on a roster config is either
+    # ABSENT (so it compared against a 2000 W DEFAULT describing no unit on the
+    # site) or a leftover from a single-inverter install (so it compared against
+    # a number no unit has). Both directions were live and both were measured:
+    #
+    #   a roster of two 2000 W units beside a leftover `max_w: 5000` and
+    #   `unit_sign_disagree_w: 3000` produced ZERO problems - the site STARTED,
+    #   with a per-inverter watchdog reporting `armed` on the status page and
+    #   incapable of tripping on EITHER unit. That is the identical sentence the
+    #   branch above exists to refuse, reached through the branch beside it;
+    #
+    #   and a roster of two 5000 W units with no flat key was REFUSED at
+    #   `unit_sign_disagree_w: 3000` against a 2000 W default the operator never
+    #   wrote, for a threshold both units can reach.
+    #
+    # `unit_caps()`'s own docstring already said why: there is no such thing as
+    # a site rating on the wire, and this watchdog grades ONE UNIT's standing
+    # command against THAT unit's `supervised` bound. So it takes the same
+    # `weakest` the branch above takes, from the same list, and names the same
+    # unit. At a roster of one `unit_caps()` is `[max_w]` and this is the
+    # identical comparison it always was - which is what keeps the shipped
+    # single-inverter refusal byte-for-byte what it was.
     unit_sign_w = _number(opts, "unit_sign_disagree_w",
                           float(SIGN_OPTION_DEFAULTS["unit_sign_disagree_w"]))
+    unit_where = (_unit_label(opts, min(caps_ix, key=lambda p: p[1])[0])
+                  if caps_ix else "")
     if unit_sign_w is None:
         problems.append(f"unit_sign_disagree_w "
                         f"{opts.get('unit_sign_disagree_w')!r} is not a number")
-    elif max_w is not None and max_w > 0 and unit_sign_w >= max_w:
+    elif weakest is not None and weakest > 0 and unit_sign_w >= weakest:
         problems.append(
-            f"unit_sign_disagree_w is {unit_sign_w:.0f} W but max_w is "
-            f"{max_w:.0f} W, so the SAFETY-30 per-inverter sign-disagreement "
+            f"unit_sign_disagree_w is {unit_sign_w:.0f} W but max_w{unit_where}"
+            f" is {weakest:.0f} W, so the SAFETY-30 per-inverter sign-disagreement "
             "watchdog can never fire: no inverter is ever commanded past max_w, "
             f"and the watchdog needs a command over {unit_sign_w:.0f} W. At two "
             "inverters that is the guard which catches a unit doing the "
             "OPPOSITE of what it was told while its sibling covers for it at "
             "the meter - the case the site-level watchdog is structurally "
-            f"blind to. Lower unit_sign_disagree_w below {max_w:.0f} W "
+            f"blind to. Lower unit_sign_disagree_w below {weakest:.0f} W "
             f"({SIGN_OPTION_DEFAULTS['unit_sign_disagree_w']:.0f} W is the "
             "measured default), or raise max_w.")
 
@@ -859,6 +1039,62 @@ def validate_startup_config(opts: dict, dev_min=None, dev_max=None) -> list[str]
             f"two numbers. Lower maintenance_charge_w to {maint_cap:.0f} W or "
             f"less, or raise max_w to at least {charge_w:.0f} W.")
 
+    # --- 10. a slew rate the plant can actually follow -----------------------
+    # ⚠️ SAFETY-39. The one rule here that grades a RATIO rather than a
+    # threshold, and the whole point of writing it as one is that the number it
+    # bounds must not be able to outlive the rail again. `control.py`'s header
+    # carries the derivation; the short version is that `slew_w: 1000` was
+    # derived against a 1500 W clamp and the live install raised the clamp to
+    # 5000 without revisiting it, so the loop traversed its whole output range
+    # in 10 s against a plant measured at ~18 s.
+    #
+    # ⚠️ `slew_w: 0` IS NOT GRADED AND MUST NOT BE. Zero means "follow the
+    # rail" - `control.slew_limit_w()` resolves it to `SLEW_RAIL_FRAC * max_w`,
+    # which satisfies this rule by construction at every rail there is. It is
+    # the shipped default, and a rule that refused it would refuse the fix.
+    #
+    # ⚠️ STRICTLY `>`, MATCHING RULE 6 RATHER THAN RULE 5. Equality is the
+    # derived value itself: at `slew_w == SLEW_RAIL_FRAC * rail` the loop takes
+    # exactly `PLANT_SETTLE_S` to cross its range, which is the constraint
+    # satisfied, not violated. Refusing it would refuse the value this rule
+    # exists to recommend - and `slew_limit_w()` produces exactly that value
+    # for every default install, so `>=` would refuse the shipped default
+    # through a float comparison. A tolerance is applied for the same reason:
+    # `SLEW_RAIL_FRAC * 5000` is 555.55..., and an operator who writes the 556
+    # a status page rounded to is one watt over a boundary that is not
+    # meaningful to one watt.
+    slew_w = _number(opts, "slew_w", 0.0)
+    rail = site_rail_w(opts)
+    if slew_w is None:
+        problems.append(f"slew_w {opts.get('slew_w')!r} is not a number")
+    elif slew_w < 0:
+        problems.append(
+            f"slew_w is {slew_w:.0f} W and must not be negative - it is a "
+            "magnitude, and 0 means 'follow max_w' (the recommended setting).")
+    elif slew_w and rail is not None and rail > 0:
+        bound = SLEW_RAIL_FRAC * rail
+        if slew_w > bound + 1.0:
+            ticks = rail / slew_w
+            problems.append(
+                f"slew_w is {slew_w:.0f} W against a site rail of {rail:.0f} W, "
+                f"so the loop crosses its whole output range in {ticks:.1f} "
+                f"cycles - {ticks * LOOP_TICK_S:.0f} s at the {LOOP_TICK_S:.0f} s "
+                f"tick this site was measured running - while the plant takes "
+                f"{PLANT_SETTLE_S:.0f} s to settle (goodwe/NOTES.md §5.10, a "
+                "1.78 kW step). The controller would command its entire range "
+                "before it could observe its answer to the first step, which is "
+                "not a slow loop, it is a loop that MANUFACTURES the error it "
+                "then chases: measured on this system 2026-09-05, a 3.4 kW "
+                "export drove the setpoint 380 -> 5000 W in five ticks, the "
+                "battery to -5154 W past a 5000 VA rating, and the grid from "
+                "3.4 kW of export to 2.8 kW of import. The stated limit - the "
+                "command moves at most slew_w per cycle, so it cannot jump "
+                "ahead of the inverter - is untrue at this rail; THE PLANT "
+                f"WINS, and it has no status row. Set slew_w to 0, which means "
+                f"'follow the rail' and resolves to {bound:.0f} W here and "
+                "moves on its own if the rail does, or write a value at or "
+                f"below {bound:.0f} W. Lower is always accepted.")
+
     # --- 7. two price sources on one site ------------------------------------
     problems.extend(_price_problems(opts))
 
@@ -871,28 +1107,39 @@ def validate_startup_config(opts: dict, dev_min=None, dev_max=None) -> list[str]
     # in-code mirror, pinned to config.yaml by test_peakguard.py, and main.py
     # reads the same one - exactly as maintenance.MAINT_OPTION_DEFAULTS now is
     # for the `maintenance_*` family.
+    #
+    # ⚠️ SAFETY-32 - GRADED ONCE PER UNIT, AND THE REFUSAL NAMES THE UNIT. One
+    # `bms_soc_floor` for two packs compares the EMS floor against whichever
+    # battery happened to be written into the flat key: a site with cut-outs of
+    # 10 % and 30 % and `peak_soc_floor: 20` STARTED, and the guard would then
+    # command a forced discharge that the second pack's BMS - not the operator's
+    # floor - is the thing that stops. That is the disarmed-backstop state this
+    # rule exists to refuse, reached through the rule itself. So the loop is over
+    # units, and `_unit_label()` is fed the ROSTER index the value came off (see
+    # `unit_bms_floors_indexed()`), because CFG-04 has just fixed the version of
+    # this that named the wrong inverter.
     soc_floor = _number(opts, "peak_soc_floor",
                         PEAK_OPTION_DEFAULTS["peak_soc_floor"])
-    bms_floor = _number(opts, "bms_soc_floor",
-                        PEAK_OPTION_DEFAULTS["bms_soc_floor"])
-    if soc_floor is None or bms_floor is None:
-        problems.append(
-            "peak_soc_floor and bms_soc_floor must both be numbers (got "
-            f"{opts.get('peak_soc_floor')!r} / {opts.get('bms_soc_floor')!r})")
-    elif soc_floor <= bms_floor:
-        problems.append(
-            f"peak_soc_floor is {soc_floor:.0f} % but the pack's own cut-out "
-            f"(bms_soc_floor) is {bms_floor:.0f} %, so SAFETY-07's forced "
-            "discharge has no EMS-side bound at all - THE BMS WINS, and it is "
-            "the pack's protection rather than yours. The guard would report a "
-            "SoC floor on its status page while being incapable of ever being "
-            "the thing that stops the discharge, and the symptom of that is a "
-            "battery repeatedly sitting at the BMS limit with no record of why "
-            f"- which looks exactly like the SoC drift the maintenance cycle "
-            f"exists to correct. Raise peak_soc_floor above {bms_floor:.0f} % "
-            f"(the shipped default is "
-            f"{PEAK_OPTION_DEFAULTS['peak_soc_floor']:.0f} %), or correct "
-            "bms_soc_floor if it does not match this pack.")
+    for _ix, _raw, bms_floor in unit_bms_floors_indexed(opts):
+        where = _unit_label(opts, _ix)
+        if soc_floor is None or bms_floor is None:
+            problems.append(
+                f"peak_soc_floor and bms_soc_floor{where} must both be numbers "
+                f"(got {opts.get('peak_soc_floor')!r} / {_raw!r})")
+        elif soc_floor <= bms_floor:
+            problems.append(
+                f"peak_soc_floor is {soc_floor:.0f} % but the pack's own cut-out "
+                f"(bms_soc_floor{where}) is {bms_floor:.0f} %, so SAFETY-07's forced "
+                "discharge has no EMS-side bound at all - THE BMS WINS, and it is "
+                "the pack's protection rather than yours. The guard would report a "
+                "SoC floor on its status page while being incapable of ever being "
+                "the thing that stops the discharge, and the symptom of that is a "
+                "battery repeatedly sitting at the BMS limit with no record of why "
+                f"- which looks exactly like the SoC drift the maintenance cycle "
+                f"exists to correct. Raise peak_soc_floor above {bms_floor:.0f} % "
+                f"(the shipped default is "
+                f"{PEAK_OPTION_DEFAULTS['peak_soc_floor']:.0f} %), or correct "
+                f"bms_soc_floor{where} if it does not match this pack.")
 
     # --- warnings: real, but not worth refusing over -------------------------
     integ = opts.get("integrator_max_w")

goodwe_controller/app/watchdog.py

@@ -331,6 +331,18 @@ SIGN_OPTION_DEFAULTS = {
     #    150 W -> 15.0 s    300 W -> 10.0 s    1000 W -> 0.0 s
     #    200 W -> 15.0 s    500 W ->  5.0 s
     #
+    # ⚠️ SAFETY-39 MOVED THAT SCHEMA FLOOR FROM 50 TO 0, AND THE CAMPAIGN ABOVE
+    # WAS NOT RE-RUN. It does not have to be, and here is the argument rather
+    # than the assurance. What these windows are about is how long the command
+    # takes to CROSS ITS RAIL - the swept worst case is the SLOWEST crossing,
+    # which is `slew_w` at its floor, 5000/50 = 100 cycles. `slew_w: 0` means
+    # "follow the rail" and resolves to `SLEW_RAIL_FRAC * max_w`, which is
+    # exactly 9 cycles at EVERY rail by construction. So the new value can never
+    # be the slowest crossing at any `max_w`, and it is strictly inside the
+    # envelope this campaign measured. An explicit number still spans 50..5000
+    # and is unchanged. If `SLEW_RAIL_FRAC` is ever loosened past 1/100, this
+    # paragraph stops being true and the campaign has to be re-run.
+    #
     # ⚠️ AND THE CURVE IS FLAT, WHICH IS THE FINDING THAT DECIDED THE SHAPE OF
     # THIS PAIR. Unlike the site comparison - where the meter is driven by the
     # LOAD and a flapping load holds it opposed for minutes - a unit's own power

goodwe_controller/config.yaml

@@ -1,5 +1,5 @@
 name: GoodWe RS485 Controller
-version: "0.6.0"
+version: "0.7.0"
 slug: goodwe_controller
 description: >-
   Drives a GoodWe ES/BP battery inverter over RS485 by emulating its smart
@@ -31,23 +31,23 @@ services:
   - mqtt:want
 
 options:
-  # --- sources (required) ---------------------------------------------------
-  meter_entity: sensor.p1_meter_active_power
-  meter_invert: false
+  # ==========================================================================
+  # HARDWARE - the inverter, its actuator and its own sensors
+  # ==========================================================================
+  setpoint_entity: ""
   soc_entity: ""
   batt_entity: ""
   batt_invert: false
-  setpoint_entity: ""
 
-  # --- ARCH-01 / CFG-04: the inverter roster ---------------------------------
   # ⚠️ EMPTY IS NOT "UNCONFIGURED", IT IS THE SINGLE-INVERTER CONFIGURATION, and
   # it is what every install that upgrades into this version lands on. An empty
-  # list means THE FIVE FLAT KEYS ABOVE DESCRIBE THE ONE INVERTER - same
-  # entities, same rating, same behaviour, no operator action - which is the
-  # only migration story this key was allowed to have. `build_roster()` reads
-  # this and nothing else decides the shape.
+  # list means THE SIX FLAT KEYS - `setpoint_entity`, `soc_entity`,
+  # `batt_entity`, `batt_invert`, `max_w` and `bms_soc_floor` - DESCRIBE THE
+  # ONE INVERTER: same entities, same rating, same behaviour, no operator
+  # action, which is the only migration story this key was allowed to have.
+  # `build_roster()` reads this and nothing else decides the shape.
   #
-  # Declared, it REPLACES those five keys rather than extending them. Each entry
+  # Declared, it REPLACES those six keys rather than extending them. Each entry
   # names its own actuator, its own rating and its own sensors:
   #
   #   inverters:
@@ -56,23 +56,58 @@ options:
   #       soc_entity: sensor.goodwe_a_soc
   #       batt_entity: sensor.goodwe_a_battery_power
   #       max_w: 5000
+  #       bms_soc_floor: 10
   #     - name: inverter-b
   #       setpoint_entity: number.goodwe_b_setpoint_w
   #       soc_entity: sensor.goodwe_b_soc
   #       batt_entity: sensor.goodwe_b_battery_power
-  #       max_w: 3000
+  #       max_w: 4600
+  #       bms_soc_floor: 10
+  #
+  # ⚠️ THE 4600 IS INVERTER B'S DATASHEET FIGURE, NOT A MEASUREMENT AND NOT A
+  # PLACEHOLDER. SPIKE-04a (2026-09-04) identified B as a GoodWe GW5048D-ES,
+  # serial `55048ESU22AW0992`, whose datasheet gives Max. Charging / Discharging
+  # Power as 4600 W; nothing will be connected to its MPPTs, so the battery path
+  # is the ceiling and the 5000 VA AC nameplate is not. The 3000 W this example
+  # used to carry was a guess made before the unit was known. ⚠️ It is STILL not
+  # measured: the datasheet prints 4600 W under BATTERY INPUT DATA, so it may be
+  # DC, and `max_w` is graded against 0x0518 - the inverter's own AC power. If it
+  # is DC the AC ceiling is nearer 4324 W. SAFETY-20's `min(max_w, dev_max)` is
+  # what settles that once the device range is read; see goodwe/NOTES.md §1.1b,
+  # which records both readings and picks neither.
+  #
+  # ⚠️ AND THE `bms_soc_floor: 10` BESIDE IT IS FROM THE SAME PLACE - THE
+  # DATASHEET AND THE SERIAL, NOT A PACK ANYONE HAS READ. No second inverter
+  # exists on this site (SPIKE-04, ≈ 2026-09-12 for B); the cut-out must be read
+  # off the pack that is actually installed (register 0x0560 on the reference
+  # unit) before that pack is commanded. It reads 10 here because pack A reads
+  # 10, which makes this example DEGENERATE ON THE FLOOR AXIS: a site whose two
+  # packs floor at the SAME percent cannot separate `min`, `max`, first or last
+  # over the roster, and every SAFETY-32 fixture that DIFFERS the floors differs
+  # it for exactly that reason. Do not "simplify" those fixtures to match this
+  # example.
   #
   # ⚠️ NOTHING IS INHERITED FROM THE FLAT KEYS BY AN ENTRY THAT OMITS IT, and
   # that is the whole of DEV-02 restated as a config rule. `soc`, `batt` and the
   # rating became per-instance precisely so that no inverter is ever graded
   # against a sibling's numbers; an entry silently inheriting `soc_entity` would
-  # rebuild that defect in YAML. `name`, `setpoint_entity` and `max_w` are
-  # therefore REQUIRED of every entry (the schema below enforces it, and
+  # rebuild that defect in YAML. `name`, `setpoint_entity`, `max_w` and
+  # `bms_soc_floor` are therefore REQUIRED of every entry (the schema below enforces it, and
   # validate.py rule 9 enforces it again for the callers the Supervisor never
   # sees). An omitted `soc_entity`/`batt_entity` means THIS UNIT HAS NO SUCH
   # SENSOR - `inputs_ok` already stops the site for that - and never means
   # "use the other one's".
   #
+  # ⚠️ SAFETY-32: `bms_soc_floor` IS PER ENTRY AND IS REQUIRED, NOT DEFAULTED.
+  # It is the percent THAT pack's own BMS cuts out at, and two batteries of
+  # different models do not share one. A default would be this add-on inventing
+  # a cut-out for a battery it has not been told about, which is the same defect
+  # as inheriting one: the shallower pack gets protected by a floor that belongs
+  # to the deeper pack, and validate.py rule 8 - which refuses a peak_soc_floor
+  # the BMS would win against - would be grading the wrong number. Rule 8 grades
+  # EVERY entry and names the one it refuses. The flat key below is unchanged and
+  # is the single-inverter shape's own cut-out.
+  #
   # ⚠️ AND THE FLAT `setpoint_entity` MUST THEN BE BLANK. Leaving it set while a
   # roster is declared is two config sites aimed at actuators, one of which
   # nothing writes; if it names an entity an entry also names, SAFETY-28's
@@ -91,9 +126,12 @@ options:
   # validator answers `Missing option 'inverters' in root` for every existing
   # options blob, and the upgrade leaves an add-on that cannot start.
   inverters: []
+  estop_fitted: false
 
-  # --- P1 meter ingestion (specs §5.2 / §14 `meter:`) -------------------------
-  # `off` keeps the original single meter_entity path above, so an existing
+  # ==========================================================================
+  # METER - where the grid reading comes from
+  # ==========================================================================
+  # `off` keeps the original single `meter_entity` path, so an existing
   # install is untouched until it opts in. ha_dsmr subscribes to the DSMR
   # integration's entities over the HA WebSocket; mqtt_p1 reads the topic below;
   # ha_signed reads ONE signed HA entity (+ import / - export), which is what a
@@ -104,209 +142,62 @@ options:
   # nothing at all for a repeated reading - so it is the only mode a firmware
   # watchdog may threshold. See DOCS.md.
   meter_source: "off"
+  meter_entity: sensor.p1_meter_active_power
+  meter_invert: false
   meter_phases: 1
-  meter_max_age_s: 30
-  meter_mqtt_topic: ""
+
   # homewizard_local only. The meter's own address, `host` or `host:port`.
   p1_host: ""
+
   # homewizard_local only. Seconds between polls. Must be well under
   # meter_max_age_s - the age is never fresher than this interval - and there is
   # nothing to gain below the meter's own ~5.0 s update rate (NOTES.md:640).
   meter_poll_s: 5
+  meter_max_age_s: 30
+  meter_mqtt_topic: ""
+
   # The two UNSIGNED Belgian registers. The EMS derives net power from them
   # (import - export); do NOT point these at a signed template sensor.
   p1_import_entity: ""
   p1_export_entity: ""
-  # Optional, in L1..L3 order. Required for the capacity-tariff peak on a
-  # three-phase connection; the list length must equal meter_phases.
-  p1_phase_import_entities: []
-  p1_phase_export_entities: []
+
   # ha_signed only. ONE signed net-power sensor: positive = import from the
   # grid, negative = export to it. Do NOT split it into two template sensors -
   # the split is done in the add-on (p1.split_signed) precisely so the sign
   # convention is tested rather than living in unreviewed YAML.
   p1_net_entity: ""
+
+  # Optional, in L1..L3 order. Required for the capacity-tariff peak on a
+  # three-phase connection; the list length must equal meter_phases.
+  p1_phase_import_entities: []
+  p1_phase_export_entities: []
+
   # Optional, in L1..L3 order, each one signed the same way. Same role as
   # p1_phase_import_entities: the capacity-tariff peak on a three-phase
   # connection. The list length must equal meter_phases.
   p1_phase_net_entities: []
 
-  # --- control ---------------------------------------------------------------
+  # ==========================================================================
+  # RATINGS AND LIMITS - what this site is allowed to do
+  # ==========================================================================
   max_w: 2000
-  gain: 0.6
-  slew_w: 1000
-  deadband_w: 15
-  target_grid_w: -10
-  step_w: 10
-  saturation_w: 500
-  saturation_cycles: 3
-  integrator_max_w: 0
-  heartbeat_s: 10
-  stale_input_s: 15
-  cycle_floor_s: 15
-  auto_start: false
 
-  # --- SAFETY-02 sign-disagreement watchdog ----------------------------------
-  # Trips when the emitted setpoint and the P1 net figure point OPPOSITE ways,
-  # both over sign_disagree_w, continuously for sign_disagree_s. Action: 0 W and
-  # a failsafe that latches until an operator starts control again.
+  # The pack's OWN cut-out percent - what the BMS enforces whatever
+  # `peak_soc_floor` is set to. Register 0x0560 reads 10 on the reference
+  # GW5000S-BP, consistent with DoD 90. It is here so validate.py can REFUSE a
+  # peak_soc_floor at or below it: such a floor can never bind, the BMS wins,
+  # and the status page would report an energy backstop that does not exist.
   #
-  # Both defaults are measured, not chosen. On the captured healthy day
-  # (2026-08-23) the longest legitimate opposed run - a load step the loop has
-  # not caught up with - is 30 s, and sign agreement over the gated samples is
-  # 93.4 %. On the captured fault day (2026-08-20) the clusters run 0.0-10.5 %
-  # agreement with opposed runs up to 1752 s. 300 W / 180 s sits in the middle of
-  # a very wide gap: at 60 s the healthy day still trips nothing, at 300 s the
-  # fault day still trips 13 times. There is no reason to move either number
-  # without a capture that says so. They are options because the AC says
-  # thresholds are defaults rather than constants - not because they are knobs
-  # anyone is expected to turn.
-  #
-  # ⚠️ sign_disagree_w must stay BELOW max_w or the watchdog can never fire (the
-  # arbiter bounds the command to +-max_w). validate.py refuses that config.
-  sign_disagree_w: 300
-  sign_disagree_s: 180
-
-  # --- SAFETY-30 per-inverter sign-disagreement watchdog ---------------------
-  # ⚠️ A DIFFERENT COMPARISON, NOT A SECOND COPY OF THE ONE ABOVE, AND IT IS
-  # ARMED ONLY WHEN THIS SITE HAS MORE THAN ONE INVERTER. The pair above grades
-  # the SITE's total command against P1 - one meter, one grid connection. This
-  # pair grades EACH inverter's own share against THAT inverter's own measured
-  # power (holding register 0x0518), and it catches the fault the meter cannot
-  # answer for once there are two units: a unit doing the opposite of what it
-  # was told, while its sibling covers for it and P1 reads exactly what a
-  # healthy site reads.
-  #
-  # At ONE inverter these two keys do nothing at all. §6.2's identity makes the
-  # site's total command that inverter's command, so the pair above is already
-  # asking this question of the same actuator, and arming a second detector
-  # would be two latches and two banners for one fault.
-  #
-  # Both defaults are measured on admin/goodwe's two-master rig, over 1890
-  # closed-loop runs in which nothing is faulty, swept across the whole range
-  # this file accepts for `gain` and `slew_w`. 250 W is `saturation_w / 2`, so
-  # the smallest divergence this can see is exactly the gap at which the control
-  # law itself already says the inverter is not following; 85 s is 8.5x the
-  # worst legitimate opposition those runs produce (10.0 s), 2.8x the firmware's
-  # own 30 s link veto, and under half the 180 s the site check takes. See
-  # app/watchdog.py's SIGN_OPTION_DEFAULTS and
-  # DECISIONS/SAFETY-30-per-unit-sign.md.
-  #
-  # ⚠️ unit_sign_disagree_w must stay BELOW max_w, for sign_disagree_w's reason:
-  # a share is bounded to +-max_w, so a threshold at or above it can never fire.
-  # validate.py refuses that config.
-  unit_sign_disagree_w: 250
-  unit_sign_disagree_s: 85
-
-  # --- SAFETY-30 SITE sign-disagreement watchdog -----------------------------
-  # ⚠️ THE SAME COMPARISON `sign_disagree_*` MAKES, AT THE ROSTER WHERE IT STOPS
-  # BEING A STATEMENT ABOUT ONE INVERTER. At two or more units the SUM of the
-  # standing commands is graded against P1, and the trip stops the whole site -
-  # what it catches is the site being asked for the wrong thing, which every
-  # per-inverter check is blind to because each unit is faithfully executing its
-  # share. At ONE inverter these two keys do nothing: `sign_disagree_*` above is
-  # already asking this of the same actuator.
-  #
-  # The threshold is the shipped 300 W, CARRIED, and the reason is that the
-  # argument behind it does not depend on the roster: near zero the sign is
-  # noise, the deadband is 15 W, and there is one P1 whatever is behind it.
-  #
-  # ⚠️ THE WINDOW IS NOT CARRIED, AND THAT IS A MEASUREMENT. The transient 180 s
-  # exists to reject is the loop crossing zero after a load reversal, and the
-  # command has to travel the whole SITE rail at `slew_w` per cycle - a rail
-  # that is the roster sum while `slew_w` is not. On 1890 two-inverter runs in
-  # which nothing is faulty, the worst continuous legitimate opposition at 300 W
-  # is 110 s at one inverter and 215 s at two: carrying 180 s across would have
-  # shipped a false trip reachable at `gain: 0.05`, `slew_w: 50` and an ordinary
-  # 2.2 kW load reversal. 325 s is 1.51x that, inside the 900 s billing quarter,
-  # and still inside every episode of the 2026-08-20 fault day.
-  site_sign_disagree_w: 300
-  site_sign_disagree_s: 325
-
-  # --- SAFETY-18 frozen-but-fresh meter detector -----------------------------
-  # Seconds the meter may keep answering with an UNCHANGED measurement while the
-  # command stands at the rail before the add-on raises an alarm. Both halves
-  # are required: neither one alone is safe, and app/freeze.py carries why.
-  #
-  # ALARM ONLY. It does not command 0 W and does not latch. A false trip parks
-  # the battery; a false notification costs an alert.
-  #
-  # ⚠️ Only `meter_source: homewizard_local` can see this at all - it is the
-  # only transport that reads the meter's own document. On every other source
-  # the status page says NOT COVERED rather than "armed".
-  #
-  # 300 s is measured, not chosen. Over 2399 s of the live house at the
-  # converged operating point (sim/scenarios/p1-age-2026-08-26.jsonl.gz, mean
-  # grid -14.2 W, 1194 polls, 735 of them repeating the previous reading) the
-  # LONGEST run without a distinct reading is 15.4 s (the largest unchanged_s any
-  # sample observes is 8.0 s). 300 s is 19.5x the pessimistic figure, and
-  # still inside the 900 s quarter that bills the capacity tariff.
-  meter_freeze_s: 300
-
-  # --- SAFETY-31: circulating power ------------------------------------------
-  # ⚠️ CFG-03. THESE TWO LINES ARE THE SOURCE OF TRUTH FOR THESE DEFAULTS, and
-  # `app/circulation.py`'s `CIRC_OPTION_DEFAULTS` is the ONE in-code copy - the
-  # Dockerfile does not put this file in the image, so the running add-on cannot
-  # read it. test_watchdog.py pins the copy by READING these lines, so a drift
-  # goes red in CI rather than shipping. Add a third option in three places -
-  # options:, schema:, CIRC_OPTION_DEFAULTS - and in no fourth.
-  #
-  # Circulating power is sum(|Bi|) - |sum(Bi)| over MEASURED per-inverter power:
-  # two inverters pushing against each other, which NETS TO ZERO AT THE METER
-  # and is therefore invisible to every other guard in this add-on. Both numbers
-  # below were measured on the TEST-19 two-master rig over 924 closed-loop runs
-  # in which nothing was faulty; circulation.py carries the curve they were read
-  # off and the argument for each. They are NOT sensitivity preferences.
-  #
-  # Both are ignored at one inverter, where the quantity is identically zero.
-  circulation_w: 700
-  circulation_hold_s: 75
-
-  # --- maintenance -----------------------------------------------------------
-  # ⚠️ CFG-03. THESE EIGHT LINES ARE THE SOURCE OF TRUTH FOR THE MAINTENANCE
-  # DEFAULTS. The Supervisor reads this file and the operator edits this file,
-  # so nothing else in the add-on gets an opinion about what a missing
-  # `maintenance_*` key means. There is exactly ONE in-code copy -
-  # `app/maintenance.py`'s `MAINT_OPTION_DEFAULTS` - because the Dockerfile does
-  # not put this file in the image and the running add-on therefore cannot read
-  # it; test_maintenance.py pins that copy by READING these lines, so a drift
-  # goes red in CI rather than shipping. main.py and validate.py both read the
-  # mirror and type no number of their own.
-  #
-  # Before this card the same defaults were written down three times and had
-  # already disagreed: this block said 2000 while main.py and MaintConfig said
-  # 2500, so an options dict with the key ABSENT passed validation at 2000 and
-  # then ran at 2500 against a 2000 W ceiling - a silent 0 W arbiter
-  # contradiction. Changing one of these numbers now moves every consumer.
-  maintenance_enabled: false
-  maintenance_interval_days: 28
-  maintenance_start_hour: 10
-  # ⚠️ BOTH MUST STAY AT OR BELOW max_w, and that is why they are 2000 rather
-  # than the 2500 they shipped as. The cheap-window charge shaping asks the
-  # arbiter for `hi = -maintenance_charge_w` against the supervised `lo =
-  # -max_w`: above the ceiling that is `lo > hi`, a contradiction resolved to
-  # 0 W, so maintenance would SILENTLY NEVER CHARGE in a cheap window on a
-  # default install. validate.py refuses that config (rule 6), so these
-  # defaults had to become self-consistent with the max_w above rather than
-  # ship a configuration the validator rejects.
-  #
-  # The discharge side is clamped rather than contradicted - it drains at max_w
-  # and the arbiter says so - so it is only warned about; it is 2000 here for
-  # symmetry and to keep the shipped config warning-free.
-  #
-  # Raising max_w (the live reference install runs 5000) is what unlocks a
-  # faster maintenance cycle. Raise max_w FIRST, then these.
-  maintenance_discharge_w: 2000
-  maintenance_charge_w: 2000
-  maintenance_soc_floor: 11
-  maintenance_soc_target: 99
-  maintenance_hold_min: 120
-
-  # --- tariff / capacity tariff (all optional) ------------------------------
-  peak_forecast_entity: ""
+  # ⚠️ SAFETY-32 - THIS KEY DESCRIBES ONE PACK, so it is the SINGLE-INVERTER
+  # shape's number and nothing more. Declare an `inverters:` roster and each
+  # entry states its own `bms_soc_floor`; this one is not read at all and is
+  # not inherited by any entry. Rule 8 then grades every unit separately, which
+  # is the whole of that card: one cut-out for two packs of different models
+  # protects the shallower pack with the deeper pack's number.
+  bms_soc_floor: 10
   peak_cap_w: 3500
+  peak_forecast_entity: ""
 
-  # --- SAFETY-24: the energy backstop under SAFETY-07's forced discharge -----
   # The peak guard can COMMAND a discharge to hold a billed quarter under
   # peak_cap_w. Until this card it was bounded from below by nothing but the
   # pack's own BMS cut-out - a real floor, but the PACK's protection rather than
@@ -350,31 +241,10 @@ options:
   # loop-side reserve and is waiting on the product owner. Until that is
   # answered, the BMS is the only floor under self-consumption.
   peak_soc_floor: 20
-  # The pack's OWN cut-out percent - what the BMS enforces whatever is set
-  # above. Register 0x0560 reads 10 on the reference GW5000S-BP, consistent with
-  # DoD 90. It is here so validate.py can REFUSE a peak_soc_floor at or below
-  # it: such a floor can never bind, the BMS wins, and the status page would
-  # report an energy backstop that does not exist.
-  bms_soc_floor: 10
 
-  # ⚠️ THE OLD PRICE PATH, AND IT IS NOT DEAD YET. These two entities are the
-  # add-on delegating the whole price question to Home Assistant: main.py reads
-  # both and derives ONE BOOLEAN, `cheap = now <= avg`, which is consumed by
-  # nothing except the maintenance cycle's cheap-window charge floor. That is
-  # all they have ever done. They are kept, because retiring them would take
-  # the maintenance cycle's only price signal away on a live install before
-  # anything replaces it - TARIFF-03 (static profile) and OPT-04 (arbitrage)
-  # are the cards that replace it, and neither has landed.
-  #
-  # ⚠️ They may NOT be combined with price_provider below. Two price sources on
-  # one site, one of which silently wins, is exactly the "double up" the PM
-  # named; validate.py rule 7 refuses that configuration at startup rather than
-  # letting an operator believe the provider they configured is driving
-  # something. See app/validate.py.
-  price_now_entity: ""
-  price_avg_entity: ""
-
-  # --- price providers (TARIFF-02, specs §9.3 / §14 `tariffs:`) --------------
+  # ==========================================================================
+  # TARIFF - what energy costs, and whether to trade on it
+  # ==========================================================================
   # `off` is the shipped default and means the §11.4 no-price-data row applies:
   # static profile, plan provisional, NO ARBITRAGE. Nothing in 0.5.x consumes
   # the series yet - OPT-04 is the consumer - so turning this on today fetches,
@@ -393,12 +263,12 @@ options:
   price_provider: "off"
   price_markup_eur_kwh: 0.03
   price_taxes_eur_kwh: 0.06
-  price_csv_path: "/share/goodwe_prices.csv"
-  price_feed_url: ""
-  price_horizon_h: 48
-  price_timeout_s: 10
 
-  # --- static / fully-fixed tariffs (TARIFF-03, specs §9.2 / §11.4) ----------
+  # §9.3: injection is priced SEPARATELY, and in Belgium it is often near zero -
+  # which by itself strongly favours self-consumption over export. A scalar, not
+  # a second series: no shipped supplier publishes a dynamic injection curve.
+  export_price_eur_kwh: 0.04
+
   # §14's `tariffs.static_profile`, and "" is its `null`. §9.2: "a large share
   # of the installed base is on [a static profile]" - this is what makes those
   # sites first-class rather than "price_provider: off, good luck".
@@ -428,13 +298,28 @@ options:
   # to fall back to and a dead feed leaves the site with no tariff at all.
   # validate.py warns about exactly that.
   static_profile: ""
+  price_csv_path: "/share/goodwe_prices.csv"
+  price_feed_url: ""
+  price_horizon_h: 48
+  price_timeout_s: 10
 
-  # §9.3: injection is priced SEPARATELY, and in Belgium it is often near zero -
-  # which by itself strongly favours self-consumption over export. A scalar, not
-  # a second series: no shipped supplier publishes a dynamic injection curve.
-  export_price_eur_kwh: 0.04
+  # ⚠️ THE OLD PRICE PATH, AND IT IS NOT DEAD YET. These two entities are the
+  # add-on delegating the whole price question to Home Assistant: main.py reads
+  # both and derives ONE BOOLEAN, `cheap = now <= avg`, which is consumed by
+  # nothing except the maintenance cycle's cheap-window charge floor. That is
+  # all they have ever done. They are kept, because retiring them would take
+  # the maintenance cycle's only price signal away on a live install before
+  # anything replaces it - TARIFF-03 (static profile) and OPT-04 (arbitrage)
+  # are the cards that replace it, and neither has landed.
+  #
+  # ⚠️ They may NOT be combined with `price_provider`. Two price sources on
+  # one site, one of which silently wins, is exactly the "double up" the PM
+  # named; validate.py rule 7 refuses that configuration at startup rather than
+  # letting an operator believe the provider they configured is driving
+  # something. See app/validate.py.
+  price_now_entity: ""
+  price_avg_entity: ""
 
-  # --- price arbitrage (OPT-04, specs §10.1 priority 3 / §17) ---------------
   # Charge in the cheapest published hour, discharge in the dearest, and ONLY
   # when the spread covers what the round trip costs. Off in the shipped
   # configuration: this is the first strategy in the add-on that moves energy
@@ -455,10 +340,12 @@ options:
   # owner; the code is correct at any value and no number was picked to make a
   # trade appear.
   arbitrage_enabled: false
+
   # §10.1's `cycle_cost_threshold_eur`: what one full round trip costs per kWh
   # - the wear on the pack plus the conversion losses. A spread below this is
   # a cycle that loses money and pack life, so it is not taken.
   cycle_cost_threshold_eur: 0.10
+
   # The reserve arbitrage may not spend, and the headroom it may not overfill.
   # Deliberately NOT the maintenance_soc_* keys: those describe a monthly
   # balancing cycle, and pointing a trading strategy at them would couple two
@@ -466,17 +353,222 @@ options:
   arbitrage_soc_floor: 20
   arbitrage_soc_ceiling: 95
 
-  # --- site ------------------------------------------------------------------
-  estop_fitted: false
+  # ==========================================================================
+  # MAINTENANCE - the monthly battery recalibration cycle
+  # ==========================================================================
+  # ⚠️ CFG-03. THESE EIGHT LINES ARE THE SOURCE OF TRUTH FOR THE MAINTENANCE
+  # DEFAULTS. The Supervisor reads this file and the operator edits this file,
+  # so nothing else in the add-on gets an opinion about what a missing
+  # `maintenance_*` key means. There is exactly ONE in-code copy -
+  # `app/maintenance.py`'s `MAINT_OPTION_DEFAULTS` - because the Dockerfile does
+  # not put this file in the image and the running add-on therefore cannot read
+  # it; test_maintenance.py pins that copy by READING these lines, so a drift
+  # goes red in CI rather than shipping. main.py and validate.py both read the
+  # mirror and type no number of their own.
+  #
+  # Before this card the same defaults were written down three times and had
+  # already disagreed: this block said 2000 while main.py and MaintConfig said
+  # 2500, so an options dict with the key ABSENT passed validation at 2000 and
+  # then ran at 2500 against a 2000 W ceiling - a silent 0 W arbiter
+  # contradiction. Changing one of these numbers now moves every consumer.
+  maintenance_enabled: false
+  maintenance_interval_days: 28
+  maintenance_start_hour: 10
+
+  # ⚠️ BOTH MUST STAY AT OR BELOW max_w, and that is why they are 2000 rather
+  # than the 2500 they shipped as. The cheap-window charge shaping asks the
+  # arbiter for `hi = -maintenance_charge_w` against the supervised `lo =
+  # -max_w`: above the ceiling that is `lo > hi`, a contradiction resolved to
+  # 0 W, so maintenance would SILENTLY NEVER CHARGE in a cheap window on a
+  # default install. validate.py refuses that config (rule 6), so these
+  # defaults had to become self-consistent with the max_w above rather than
+  # ship a configuration the validator rejects.
+  #
+  # The discharge side is clamped rather than contradicted - it drains at max_w
+  # and the arbiter says so - so it is only warned about; it is 2000 here for
+  # symmetry and to keep the shipped config warning-free.
+  #
+  # Raising max_w (the live reference install runs 5000) is what unlocks a
+  # faster maintenance cycle. Raise max_w FIRST, then these.
+  maintenance_discharge_w: 2000
+  maintenance_charge_w: 2000
+  maintenance_soc_floor: 11
+  maintenance_soc_target: 99
+  maintenance_hold_min: 120
+
+  # ==========================================================================
+  # SAFETY - DERIVED CONSTANTS. Every number below was measured. Do not change
+  # one without re-deriving it
+  # ==========================================================================
+  # Trips when the emitted setpoint and the P1 net figure point OPPOSITE ways,
+  # both over sign_disagree_w, continuously for sign_disagree_s. Action: 0 W and
+  # a failsafe that latches until an operator starts control again.
+  #
+  # Both defaults are measured, not chosen. On the captured healthy day
+  # (2026-08-23) the longest legitimate opposed run - a load step the loop has
+  # not caught up with - is 30 s, and sign agreement over the gated samples is
+  # 93.4 %. On the captured fault day (2026-08-20) the clusters run 0.0-10.5 %
+  # agreement with opposed runs up to 1752 s. 300 W / 180 s sits in the middle of
+  # a very wide gap: at 60 s the healthy day still trips nothing, at 300 s the
+  # fault day still trips 13 times. There is no reason to move either number
+  # without a capture that says so. They are options because the AC says
+  # thresholds are defaults rather than constants - not because they are knobs
+  # anyone is expected to turn.
+  #
+  # ⚠️ sign_disagree_w must stay BELOW max_w or the watchdog can never fire (the
+  # arbiter bounds the command to +-max_w). validate.py refuses that config.
+  sign_disagree_w: 300
+  sign_disagree_s: 180
+
+  # ⚠️ A DIFFERENT COMPARISON, NOT A SECOND COPY OF THE ONE ABOVE, AND IT IS
+  # ARMED ONLY WHEN THIS SITE HAS MORE THAN ONE INVERTER. The pair above grades
+  # the SITE's total command against P1 - one meter, one grid connection. This
+  # pair grades EACH inverter's own share against THAT inverter's own measured
+  # power (holding register 0x0518), and it catches the fault the meter cannot
+  # answer for once there are two units: a unit doing the opposite of what it
+  # was told, while its sibling covers for it and P1 reads exactly what a
+  # healthy site reads.
+  #
+  # At ONE inverter these two keys do nothing at all. §6.2's identity makes the
+  # site's total command that inverter's command, so the pair above is already
+  # asking this question of the same actuator, and arming a second detector
+  # would be two latches and two banners for one fault.
+  #
+  # Both defaults are measured on admin/goodwe's two-master rig, over 1890
+  # closed-loop runs in which nothing is faulty, swept across the whole range
+  # this file accepts for `gain` and `slew_w`. 250 W is `saturation_w / 2`, so
+  # the smallest divergence this can see is exactly the gap at which the control
+  # law itself already says the inverter is not following; 85 s is 8.5x the
+  # worst legitimate opposition those runs produce (10.0 s), 2.8x the firmware's
+  # own 30 s link veto, and under half the 180 s the site check takes. See
+  # app/watchdog.py's SIGN_OPTION_DEFAULTS and
+  # DECISIONS/SAFETY-30-per-unit-sign.md.
+  #
+  # ⚠️ unit_sign_disagree_w must stay BELOW max_w, for sign_disagree_w's reason:
+  # a share is bounded to +-max_w, so a threshold at or above it can never fire.
+  # validate.py refuses that config.
+  unit_sign_disagree_w: 250
+  unit_sign_disagree_s: 85
+
+  # ⚠️ THE SAME COMPARISON `sign_disagree_*` MAKES, AT THE ROSTER WHERE IT STOPS
+  # BEING A STATEMENT ABOUT ONE INVERTER. At two or more units the SUM of the
+  # standing commands is graded against P1, and the trip stops the whole site -
+  # what it catches is the site being asked for the wrong thing, which every
+  # per-inverter check is blind to because each unit is faithfully executing its
+  # share. At ONE inverter these two keys do nothing: `sign_disagree_*` above is
+  # already asking this of the same actuator.
+  #
+  # The threshold is the shipped 300 W, CARRIED, and the reason is that the
+  # argument behind it does not depend on the roster: near zero the sign is
+  # noise, the deadband is 15 W, and there is one P1 whatever is behind it.
+  #
+  # ⚠️ THE WINDOW IS NOT CARRIED, AND THAT IS A MEASUREMENT. The transient 180 s
+  # exists to reject is the loop crossing zero after a load reversal, and the
+  # command has to travel the whole SITE rail at `slew_w` per cycle - a rail
+  # that is the roster sum while `slew_w` is not. On 1890 two-inverter runs in
+  # which nothing is faulty, the worst continuous legitimate opposition at 300 W
+  # is 110 s at one inverter and 215 s at two: carrying 180 s across would have
+  # shipped a false trip reachable at `gain: 0.05`, `slew_w: 50` and an ordinary
+  # 2.2 kW load reversal. 325 s is 1.51x that, inside the 900 s billing quarter,
+  # and still inside every episode of the 2026-08-20 fault day.
+  site_sign_disagree_w: 300
+  site_sign_disagree_s: 325
+
+  # Seconds the meter may keep answering with an UNCHANGED measurement while the
+  # command stands at the rail before the add-on raises an alarm. Both halves
+  # are required: neither one alone is safe, and app/freeze.py carries why.
+  #
+  # ALARM ONLY. It does not command 0 W and does not latch. A false trip parks
+  # the battery; a false notification costs an alert.
+  #
+  # ⚠️ Only `meter_source: homewizard_local` can see this at all - it is the
+  # only transport that reads the meter's own document. On every other source
+  # the status page says NOT COVERED rather than "armed".
+  #
+  # 300 s is measured, not chosen. Over 2399 s of the live house at the
+  # converged operating point (sim/scenarios/p1-age-2026-08-26.jsonl.gz, mean
+  # grid -14.2 W, 1194 polls, 735 of them repeating the previous reading) the
+  # LONGEST run without a distinct reading is 15.4 s (the largest unchanged_s any
+  # sample observes is 8.0 s). 300 s is 19.5x the pessimistic figure, and
+  # still inside the 900 s quarter that bills the capacity tariff.
+  meter_freeze_s: 300
+
+  # ⚠️ CFG-03. THESE TWO LINES ARE THE SOURCE OF TRUTH FOR THESE DEFAULTS, and
+  # `app/circulation.py`'s `CIRC_OPTION_DEFAULTS` is the ONE in-code copy - the
+  # Dockerfile does not put this file in the image, so the running add-on cannot
+  # read it. test_watchdog.py pins the copy by READING these lines, so a drift
+  # goes red in CI rather than shipping. Add a third option in three places -
+  # options:, schema:, CIRC_OPTION_DEFAULTS - and in no fourth.
+  #
+  # Circulating power is sum(|Bi|) - |sum(Bi)| over MEASURED per-inverter power:
+  # two inverters pushing against each other, which NETS TO ZERO AT THE METER
+  # and is therefore invisible to every other guard in this add-on. Both numbers
+  # below were measured on the TEST-19 two-master rig over 924 closed-loop runs
+  # in which nothing was faulty; circulation.py carries the curve they were read
+  # off and the argument for each. They are NOT sensitivity preferences.
+  #
+  # Both are ignored at one inverter, where the quantity is identically zero.
+  circulation_w: 700
+  circulation_hold_s: 75
+
+  # ==========================================================================
+  # ADVANCED - the control law and diagnostics
+  # ==========================================================================
+  auto_start: false
+  gain: 0.6
+
+  # ⚠️ SAFETY-39. 0 IS NOT "UNSET" AND IT IS NOT "NO LIMIT" - IT IS "FOLLOW THE
+  # RAIL", and it is the shipped value. `control.slew_limit_w()` resolves it to
+  # `SLEW_RAIL_FRAC * max_w`, which is 222 W against the 2000 W default here,
+  # 556 W against the live install's 5000 W, and 1067 W against the ~9600 W a
+  # second inverter makes of the site. `integrator_max_w: 0` two lines down has
+  # meant exactly this since it was added; this key now means it too.
+  #
+  # ⚠️ WHY IT IS A RATIO AND NOT A NUMBER, WHICH IS THE WHOLE OF THIS CARD. It
+  # WAS a number: 1000, derived 2026-08-22 against a clamp of 1500 W
+  # (goodwe/NOTES.md, "Simulated 2 kW load step (gain 0.6, clamp 1500)") on the
+  # grounds that it caps "how far the loop can jump ahead of the inverter". The
+  # rail then went to 5000 on the live install and the constant did not move, so
+  # 1000 W per 2 s tick crossed the whole output range in 10 s against a plant
+  # NOTES.md §5.10 measured at ~18 s up / ~23 s down. Measured on the owner's
+  # system 2026-09-05 11:43-11:46: a 3.4 kW export drove the setpoint 380 -> 5000
+  # in five ticks, the battery to -5154 W past a 5000 VA rating, and the grid
+  # from 3.4 kW of EXPORT to 2.8 kW of IMPORT. Large (>= 900 W) steps per 30 min
+  # went 2 -> 1 -> 13 -> 43 that morning. Nothing was broken; the rail moved.
+  #
+  # An explicit number is still accepted and is not clamped - the live install
+  # has run 400 since 2026-09-05 12:00, which is slower than the rail implies
+  # and is fine. What validate.py rule 10 refuses is a number FASTER than the
+  # rail implies, because at that setting the stated limit is not the limit and
+  # the layer that overrules it is the plant, which has no status row.
+  #
+  # ⚠️ AND THE COST IS REAL AND IS NOT HIDDEN: following the rail is slower to
+  # converge than 1000 was. Measured over 51 export steps on the in-repo model
+  # (test_control.py) the largest tick step falls from 1000 W to 556 W and the
+  # >= 900 W step disappears from every run - but the OVER-ABSORPTION does not
+  # move, because that is a `gain` term and not a slew term. See
+  # DECISIONS/SAFETY-39-slew-against-the-rail.md, which says so at length rather
+  # than letting this card be read as more than it is.
+  slew_w: 0
+  deadband_w: 15
+  target_grid_w: -10
+  step_w: 10
+  saturation_w: 500
+  saturation_cycles: 3
+  integrator_max_w: 0
+  heartbeat_s: 10
+  stale_input_s: 15
+  cycle_floor_s: 15
   log_level: info
 
 schema:
-  meter_entity: str
-  meter_invert: bool
+  # ==========================================================================
+  # HARDWARE - the inverter, its actuator and its own sensors
+  # ==========================================================================
+  setpoint_entity: str
   soc_entity: str
   batt_entity: str
   batt_invert: bool
-  setpoint_entity: str
 
   # CFG-04. THE ONE LIST-OF-OBJECTS IN THIS FILE, and see the options block for
   # the measurement that says Supervisor 2026.08.0 accepts it: nested types are
@@ -500,44 +592,121 @@ schema:
     - name: str
       setpoint_entity: str
       max_w: int(100,5000)
+      bms_soc_floor: int(0,50)
       soc_entity: str?
       batt_entity: str?
       batt_invert: bool?
 
+  estop_fitted: bool
+
+  # ==========================================================================
+  # METER - where the grid reading comes from
+  # ==========================================================================
   meter_source: list(off|ha_dsmr|mqtt_p1|ha_signed|homewizard_local)
+  meter_entity: str
+  meter_invert: bool
+
   # ⚠️ 2 is accepted by this range but is not a real Belgian connection. A
   # telegram whose phase count disagrees is rejected at ingest and logged, so a
   # mis-set 2 shows up immediately as "0 telegrams accepted" rather than as a
   # quietly wrong number.
   meter_phases: int(1,3)
-  meter_max_age_s: int(5,300)
-  meter_poll_s: int(1,60)
-  meter_mqtt_topic: str?
   p1_host: str?
+  meter_poll_s: int(1,60)
+  meter_max_age_s: int(5,300)
+  meter_mqtt_topic: str?
   p1_import_entity: str?
   p1_export_entity: str?
+  p1_net_entity: str?
   p1_phase_import_entities:
     - str
+
   p1_phase_export_entities:
     - str
-  p1_net_entity: str?
+
   p1_phase_net_entities:
     - str
 
+  # ==========================================================================
+  # RATINGS AND LIMITS - what this site is allowed to do
+  # ==========================================================================
   max_w: int(100,5000)
-  gain: float(0.05,1.0)
-  slew_w: int(50,5000)
-  deadband_w: int(0,500)
-  target_grid_w: float(-200,200)
-  step_w: int(1,100)
-  saturation_w: int(100,2000)
-  saturation_cycles: int(1,10)
-  integrator_max_w: int(0,15000)
-  heartbeat_s: int(2,25)
-  stale_input_s: int(5,120)
-  cycle_floor_s: int(5,60)
-  auto_start: bool
+  bms_soc_floor: int(0,50)
+  peak_cap_w: int(500,15000)
+  peak_forecast_entity: str?
 
+  # SAFETY-24. No "off" value: a guard that can command a discharge does not get
+  # a supported way to have no energy bound at all. The ranges OVERLAP on
+  # purpose - the schema cannot express "above bms_soc_floor", so validate.py
+  # rule 8 is what refuses the pair, with a message naming both numbers.
+  peak_soc_floor: int(5,60)
+
+  # ==========================================================================
+  # TARIFF - what energy costs, and whether to trade on it
+  # ==========================================================================
+  # ⚠️ The provider list is written out rather than left as `str`, so the
+  # Supervisor rejects a typo in the UI. validate.py ALSO refuses an unknown id
+  # against app/price.py's PROVIDERS registry, because sim/inject.py and the
+  # checks reach validate_startup_config() with a dict the Supervisor never saw.
+  # Adding a sixth plugin means adding it here and to PROVIDERS - and nowhere
+  # else, which is AC2.
+  price_provider: list(off|generic_dayahead|engie_dynamic|totalenergies_dynamic|eneco_eddy|manual_csv)
+  price_markup_eur_kwh: float(0,1)
+  price_taxes_eur_kwh: float(0,1)
+
+  # ⚠️ The lower bound is NEGATIVE on purpose. Belgian injection tariffs have
+  # gone below zero (you pay to export at midday in summer), and a schema that
+  # bottoms out at 0 would make that site inexpressible.
+  export_price_eur_kwh: float(-1,1)
+
+  # A JSON string rather than a nested schema, deliberately: it is ONE option
+  # key (§14 has one), it survives config.yaml's flat options block, and
+  # parse_static_profile() accepts an already-parsed dict too, so a future
+  # nested schema is a config.yaml change and no code change at all.
+  static_profile: str?
+  price_csv_path: str?
+  price_feed_url: str?
+  price_horizon_h: int(1,72)
+  price_timeout_s: int(2,60)
+  price_now_entity: str?
+  price_avg_entity: str?
+
+  # OPT-04. ⚠️ The threshold's lower bound is 0 and not negative: it is a COST,
+  # and a negative one is a threshold every spread clears - arbitrage with the
+  # brake removed. app/arbitrage.py refuses it in code too, because
+  # validate_startup_config() is also sim/inject.py's entry point and can be
+  # handed any dict at all.
+  arbitrage_enabled: bool
+  cycle_cost_threshold_eur: float(0,1)
+  arbitrage_soc_floor: int(5,95)
+  arbitrage_soc_ceiling: int(10,100)
+
+  # ==========================================================================
+  # MAINTENANCE - the monthly battery recalibration cycle
+  # ==========================================================================
+  # ⚠️ CFG-03 - THIS IS WHERE A RANGE LIVES, AND THE ONLY PLACE IT LIVES. The
+  # `options:` block above holds the DEFAULT; this block holds the BOUNDS, and
+  # `MAINT_OPTION_DEFAULTS` deliberately mirrors the former and not the latter -
+  # the Supervisor is what enforces a range and the Supervisor reads only this
+  # file, so a second copy of `int(500,5000)` in Python would be a place to
+  # disagree and nothing else. What is NOT expressible here is a relation
+  # BETWEEN keys: `maintenance_charge_w` must also stay at or below `max_w`, the
+  # schema grammar has no way to say so, and that is why validate.py's rule 6 is
+  # written in code instead. Add a ninth maintenance option in three places -
+  # options:, schema:, MAINT_OPTION_DEFAULTS - and in no fourth.
+  maintenance_enabled: bool
+  maintenance_interval_days: int(1,90)
+  maintenance_start_hour: int(0,23)
+  maintenance_discharge_w: int(500,5000)
+  maintenance_charge_w: int(500,5000)
+  maintenance_soc_floor: int(5,30)
+  maintenance_soc_target: int(50,100)
+  maintenance_hold_min: int(5,480)
+
+  # ==========================================================================
+  # SAFETY - DERIVED CONSTANTS. Every number below was measured. Do not change
+  # one without re-deriving it
+  # ==========================================================================
   # No "off" value, deliberately: this is a P0 safety check and the schema is
   # not the place to make disarming it a supported configuration.
   sign_disagree_w: int(50,5000)
@@ -553,6 +722,7 @@ schema:
   # this range puts the guard outside the regime it can be answered for, and the
   # floor does not have to be a knee the way `circulation_w`'s does.
   unit_sign_disagree_w: int(50,5000)
+
   # The floor of 30 is `inverter.LINK_STALE_S`, the firmware's own veto window:
   # below it, a unit not executing its share is a LINK fault the add-on already
   # answers by dropping the unit from the split, and firing inside that window
@@ -593,6 +763,7 @@ schema:
   # fault. A configurable value under 400 W would be a false-alarm generator
   # that this project's own doctrine (SAFETY-15, SAFETY-19) forbids shipping.
   circulation_w: int(400,5000)
+
   # The floor of 30 is `inverter.LINK_STALE_S`: below the firmware's own veto
   # window a unit still executing a stale share is a LINK fault the add-on
   # already handles by dropping it from the split, and firing inside that window
@@ -601,68 +772,28 @@ schema:
   # loop must be caught and acted on well inside one.
   circulation_hold_s: int(30,900)
 
-  # ⚠️ CFG-03 - THIS IS WHERE A RANGE LIVES, AND THE ONLY PLACE IT LIVES. The
-  # `options:` block above holds the DEFAULT; this block holds the BOUNDS, and
-  # `MAINT_OPTION_DEFAULTS` deliberately mirrors the former and not the latter -
-  # the Supervisor is what enforces a range and the Supervisor reads only this
-  # file, so a second copy of `int(500,5000)` in Python would be a place to
-  # disagree and nothing else. What is NOT expressible here is a relation
-  # BETWEEN keys: `maintenance_charge_w` must also stay at or below `max_w`, the
-  # schema grammar has no way to say so, and that is why validate.py's rule 6 is
-  # written in code instead. Add a ninth maintenance option in three places -
-  # options:, schema:, MAINT_OPTION_DEFAULTS - and in no fourth.
-  maintenance_enabled: bool
-  maintenance_interval_days: int(1,90)
-  maintenance_start_hour: int(0,23)
-  maintenance_discharge_w: int(500,5000)
-  maintenance_charge_w: int(500,5000)
-  maintenance_soc_floor: int(5,30)
-  maintenance_soc_target: int(50,100)
-  maintenance_hold_min: int(5,480)
+  # ==========================================================================
+  # ADVANCED - the control law and diagnostics
+  # ==========================================================================
+  auto_start: bool
+  gain: float(0.05,1.0)
 
-  peak_forecast_entity: str?
-  peak_cap_w: int(500,15000)
-  # SAFETY-24. No "off" value: a guard that can command a discharge does not get
-  # a supported way to have no energy bound at all. The ranges OVERLAP on
-  # purpose - the schema cannot express "above bms_soc_floor", so validate.py
-  # rule 8 is what refuses the pair, with a message naming both numbers.
-  peak_soc_floor: int(5,60)
-  bms_soc_floor: int(0,50)
-  price_now_entity: str?
-  price_avg_entity: str?
-
-  # ⚠️ The provider list is written out rather than left as `str`, so the
-  # Supervisor rejects a typo in the UI. validate.py ALSO refuses an unknown id
-  # against app/price.py's PROVIDERS registry, because sim/inject.py and the
-  # checks reach validate_startup_config() with a dict the Supervisor never saw.
-  # Adding a sixth plugin means adding it here and to PROVIDERS - and nowhere
-  # else, which is AC2.
-  price_provider: list(off|generic_dayahead|engie_dynamic|totalenergies_dynamic|eneco_eddy|manual_csv)
-  price_markup_eur_kwh: float(0,1)
-  price_taxes_eur_kwh: float(0,1)
-  price_csv_path: str?
-  price_feed_url: str?
-  price_horizon_h: int(1,72)
-  price_timeout_s: int(2,60)
-  # A JSON string rather than a nested schema, deliberately: it is ONE option
-  # key (§14 has one), it survives config.yaml's flat options block, and
-  # parse_static_profile() accepts an already-parsed dict too, so a future
-  # nested schema is a config.yaml change and no code change at all.
-  static_profile: str?
-  # ⚠️ The lower bound is NEGATIVE on purpose. Belgian injection tariffs have
-  # gone below zero (you pay to export at midday in summer), and a schema that
-  # bottoms out at 0 would make that site inexpressible.
-  export_price_eur_kwh: float(-1,1)
-
-  # OPT-04. ⚠️ The threshold's lower bound is 0 and not negative: it is a COST,
-  # and a negative one is a threshold every spread clears - arbitrage with the
-  # brake removed. app/arbitrage.py refuses it in code too, because
-  # validate_startup_config() is also sim/inject.py's entry point and can be
-  # handed any dict at all.
-  arbitrage_enabled: bool
-  cycle_cost_threshold_eur: float(0,1)
-  arbitrage_soc_floor: int(5,95)
-  arbitrage_soc_ceiling: int(10,100)
-
-  estop_fitted: bool
+  # ⚠️ THE FLOOR IS 0, NOT 50, AND 0 IS THE SHIPPED VALUE - see the options block
+  # above. It means "follow max_w", so the range starts at the setting that
+  # cannot go stale rather than at the smallest number somebody could type.
+  # ⚠️ THE CEILING IS STILL 5000 AND IS STILL NOT THE BOUND THAT MATTERS. The
+  # binding one is `SLEW_RAIL_FRAC * max_w`, a relation BETWEEN keys, and this
+  # grammar cannot express a relation - which is the same reason
+  # `maintenance_charge_w`'s ceiling is not its real bound either (see the note
+  # above it). validate.py rule 10 is where it is written.
+  slew_w: int(0,5000)
+  deadband_w: int(0,500)
+  target_grid_w: float(-200,200)
+  step_w: int(1,100)
+  saturation_w: int(100,2000)
+  saturation_cycles: int(1,10)
+  integrator_max_w: int(0,15000)
+  heartbeat_s: int(2,25)
+  stale_input_s: int(5,120)
+  cycle_floor_s: int(5,60)
   log_level: list(trace|debug|info|warning|error)

goodwe_controller/test_alloc.py

@@ -580,7 +580,16 @@ def close_loop(gain, split, cycles=200, load_w=2000.0, mode="alloc",
     below. "site" is the sum of the units' power; "unit" is inverter A's alone,
     which is what the shipped add-on's single `inverter_power` sensor gives it.
     """
-    tuning = Tuning(gain=gain)
+    # ⚠️ `slew_w` IS PINNED HERE AND WAS NOT BEFORE, AND THAT IS SAFETY-39.
+    # ARCH-01's 4000 W peak-to-peak broadcast limit cycle was measured at the
+    # shipped pair of the day - `max_w: 2000` with `slew_w: 1000` - and this
+    # function reached that 1000 through `Tuning`'s DEFAULT. SAFETY-39 made that
+    # default 0, meaning "follow the rail" (`SLEW_RAIL_FRAC * max_w`, 222 W at
+    # this rail), so the same call would now sweep a DIFFERENT law and report
+    # ARCH-01's measurement as absent. A reproduction that silently re-tunes
+    # itself when a default moves is not a reproduction. The number is written
+    # here, next to the measurement it belongs to.
+    tuning = Tuning(gain=gain, slew_w=1000.0)
     prev, i_w, sat = 0.0, None, 0
     power = [0.0, 0.0]
     grid = load_w

goodwe_controller/test_arbiter.py

@@ -449,9 +449,32 @@ mis_peak = SITE_SIDE[:1] + [Claim.limit("peak", P_PEAK, lo=1500.0,
 r_mis = resolve(mis_peak)
 print(f"    peak floor misfiled on inverter-b: {r_mis.explain()}   "
       f"scope_errors={r_mis.scope_errors}")
-check("the mis-routing is CAUGHT: scope_violations names the source and the "
-      "actuator it does not belong on", len(r_mis.scope_errors) == 1
-      and "peak" in r_mis.scope_errors[0])
+# ⚠️ THE ORDERED PAIR, AND THE CHECK THAT USED TO BE HERE WAS WIDER THAN ITS
+# OWN CLAIM. It said `scope_violations` "names the source and the actuator it
+# does not belong on" and then asserted `"peak" in r_mis.scope_errors[0]`.
+# `arbiter.py:264` builds that sentence as
+# `f"{c.source}: a SITE claim filed on unit {c.actuator!r} - …"`; transpose the
+# two - zero bytes, no decision changes, SAFETY-38 census B row B12 - and it
+# reads "inverter-b: a SITE claim filed on unit 'peak'", naming the misfiled
+# claim as the actuator and the actuator as the claim. `"peak" in …` is STILL
+# TRUE under that, so the old line graded neither half of what it claimed.
+# The operands are read off the CLAIM this test built, not off the message.
+_mis_c = mis_peak[-1]
+check("PRECONDITION: the misfiled claim's source and actuator are DIFFERENT "
+      "STRINGS, so a transposition genuinely produces a different sentence",
+      _mis_c.source != _mis_c.actuator and _mis_c.source == "peak"
+      and _mis_c.actuator == "inverter-b")
+check("the mis-routing is CAUGHT, and scope_violations names the source FIRST "
+      "and the actuator it does not belong on SECOND - the ORDERED PAIR on the "
+      "contiguous literal, because a substring test finds either name under a "
+      "transposition that swaps their roles",
+      len(r_mis.scope_errors) == 1
+      and r_mis.scope_errors[0].startswith(
+          f"{_mis_c.source}: a SITE claim filed on unit {_mis_c.actuator!r}"))
+check("...and the TRANSPOSED sentence is not what it says, so the check above "
+      "discriminates rather than decorates",
+      f"{_mis_c.actuator}: a SITE claim filed on unit {_mis_c.source!r}"
+      not in r_mis.scope_errors[0])
 check("...and the reason it must be caught, measured rather than argued: with "
       "the floor on a unit the SITE has no floor, so the loop charges 1500 W "
       "into the quarter the guard was trying to shave",

goodwe_controller/test_clamp.py

@@ -78,7 +78,8 @@ import sys
 from datetime import datetime, timedelta, timezone
 
 from app.clamp import (
-    CLEAR_CYCLES, REASON_CODE, REASSERT_S, ClampWatchdog, clamp_to_rating,
+    CLEAR_CYCLES, REASON_CODE, REASSERT_S, SUSTAINED_CYCLES, ClampWatchdog,
+    clamp_to_rating,
     is_commandable,
 )
 from app.allocator import Allocation, UnitPlan, plan
@@ -239,11 +240,112 @@ print(f"    pinned on the rail for {QUARTER_S:.0f} s at 1 s cycles: "
 check(f"a loop pinned for a whole billing quarter speaks at least "
       f"{MIN_PER_QUARTER} times (it spoke {alarms})",
       alarms >= MIN_PER_QUARTER)
+# ⚠️ REVIEW-FOUND, SAFETY-41, and it is the SAME DEFECT as the one recorded
+# twenty lines above, one notch weaker. The sweep above runs i = 0..899 and the
+# rising edge at i=0 is FREE, so it measures `1 + floor(899 / REASSERT_S)` - one
+# alarm more than a real quarter earns. Measured on this very check:
+#   REASSERT_S = 180 -> 5 alarms, green   (and 180 is the true edge: on the worst
+#   REASSERT_S = 224 -> 5 alarms, GREEN    sliding 900 s window 180 gives 5 and
+#   REASSERT_S = 225 -> 4 alarms, red      181 gives 4)
+# So the check as written permits 224 s while the REQUIREMENT permits 180 s, and
+# anyone raising the constant to 200 s would get a green suite and conclude the
+# floor was met when a real quarter would earn 4 alarms. Grade the cadence
+# DIRECTLY, so the check enforces the ceiling its own comment claims for it.
+check(f"...and the CADENCE itself honours the floor, independent of where the "
+      f"sweep happens to start: floor({QUARTER_S:.0f}/{REASSERT_S:.0f}) = "
+      f"{int(QUARTER_S // REASSERT_S)} >= {MIN_PER_QUARTER}",
+      QUARTER_S // REASSERT_S >= MIN_PER_QUARTER)
 check(f"...and on no more than {MAX_FRACTION:.0%} of cycles (it was "
       f"{alarms / QUARTER_S:.1%})", alarms <= MAX_FRACTION * QUARTER_S)
 check("...while every single cycle is still counted",
       pinned.engagements == int(QUARTER_S))
 
+# --- THE SCATTERED REGIME, WHICH IS THE ONE THE OWNER ACTUALLY HIT -----------
+# ⚠️ REVIEW-FOUND, SAFETY-41, and it falsified the first version of this card.
+# The rising edge used to fire UNCONDITIONALLY, so REASSERT_S governed only the
+# still-engaged path. A condition that engages and clears repeatedly therefore
+# raised one notification PER EPISODE at any value of the constant.
+#
+# That is what the live install produced: 48 engagements in ~25 minutes,
+# scattered about one cycle in six. At the measured ~5 s cycle the gaps are ~25 s
+# of clean cycles, past CLEAR_CYCLES x 5 s = 15 s, so the alarm de-asserted
+# between almost every engagement. Raising REASSERT_S 30 -> 150 removed NONE of
+# them. The interval now bounds the notification RATE across episodes.
+#
+# The stimulus is written in wall-clock seconds and in the shape the field
+# actually produced, so it does not move when the constant does.
+SCATTER_CYCLE_S = 5.0
+SCATTER_ONE_IN = 6
+SCATTER_CYCLES = 305
+
+scat = ClampWatchdog()
+scat_alarms = sum(1 for i in range(SCATTER_CYCLES)
+                  if scat.note(i % SCATTER_ONE_IN == 0, "scattered",
+                               T0 + timedelta(seconds=SCATTER_CYCLE_S * i)))
+_scat_span = SCATTER_CYCLE_S * SCATTER_CYCLES
+print(f"    scattered 1-in-{SCATTER_ONE_IN} over {_scat_span:.0f} s at "
+      f"{SCATTER_CYCLE_S:.0f} s cycles: {scat.episodes} episodes, "
+      f"{scat.engagements} engagements, {scat_alarms} alarm(s)")
+check(f"a condition that de-asserts between engagements is rate-limited ACROSS "
+      f"episodes, not once per episode ({scat_alarms} alarms for "
+      f"{scat.episodes} episodes)",
+      scat_alarms < scat.episodes)
+check(f"...and the rate honours the same interval the pinned case does: at most "
+      f"ceil({_scat_span:.0f}/{REASSERT_S:.0f}) + 1 = "
+      f"{int(_scat_span // REASSERT_S) + 1}",
+      scat_alarms <= int(_scat_span // REASSERT_S) + 1)
+check("...while EVERY episode and EVERY engagement is still counted - the "
+      "budget is on notifications, never on evidence",
+      scat.episodes == scat.engagements == SCATTER_CYCLES // SCATTER_ONE_IN + 1)
+# ⚠️ THE COUNTERFACTUAL, AND THE FIRST VERSION OF IT COULD NOT FAIL FOR THE
+# DEFECT IT NAMED. It read `ClampWatchdog().note(True, ...) is True` - a FRESH
+# object, so it only ever exercised the `last_alarm is None` branch, which is the
+# trivially-true one. A fresh watchdog has no earlier episode to be held back BY.
+# That is the third instance in this file of the family recorded at line 216 and
+# at the 224 s sweep, and it was guarding the most safety-critical property in
+# the change. Review found it.
+#
+# The stimulus must therefore SPEND THE BUDGET FIRST: a benign one-cycle clamp,
+# a gap long enough to de-assert, then a continuous runaway. Without the
+# escalation clause the runaway's first notification is held for up to
+# REASSERT_S - measured at 140 s before it was added.
+_esc = ClampWatchdog()
+_esc.note(True, "benign", T0)                                   # spends the budget
+for _i in range(1, 1 + CLEAR_CYCLES + 1):                       # de-assert
+    _esc.note(False, "", T0 + timedelta(seconds=5.0 * _i))
+_RUNAWAY_AT = 5.0 * (CLEAR_CYCLES + 2)
+_esc_fires = [5.0 * (CLEAR_CYCLES + 2 + _j)
+              for _j in range(200)
+              if _esc.note(True, "runaway",
+                           T0 + timedelta(seconds=5.0 * (CLEAR_CYCLES + 2 + _j)))]
+_esc_delay = _esc_fires[0] - _RUNAWAY_AT if _esc_fires else None
+print(f"    budget spent by a benign episode, then a continuous runaway from "
+      f"t={_RUNAWAY_AT:.0f}s: first alarm at t={_esc_fires[0]:.0f}s "
+      f"(delay {_esc_delay:.0f}s)")
+check(f"⚠️ a SUSTAINED runaway speaks even when an earlier, unrelated episode "
+      f"spent the budget - it is not held for REASSERT_S ({_esc_delay:.0f}s "
+      f"delay, escalation is {SUSTAINED_CYCLES} cycles)",
+      _esc_delay is not None and _esc_delay < REASSERT_S / 2)
+check("...and it speaks at the escalation boundary rather than immediately, "
+      "which is what keeps the scattered flood suppressed",
+      _esc_delay >= 5.0 * (SUSTAINED_CYCLES - 1))
+
+# ⚠️ `last_alarm` SURVIVING THE DE-ASSERT IS NOW LOAD-BEARING, AND NOTHING
+# PINNED IT. Review built the mutation: if the de-assert path ALSO refreshed
+# `last_alarm = now`, the chatter case collapses from 50 notifications to 1 - the
+# alarm never fires again. That is the "alarm that never fires" class, which is a
+# different bug from one that fires later, and the suite was green on it.
+_starve = ClampWatchdog()
+_starve_fires = sum(1 for _i in range(1600)
+                    if _starve.note(_i % 4 == 0, "chatter",
+                                    T0 + timedelta(seconds=5.0 * _i)))
+print(f"    chatter 1-engaged/{CLEAR_CYCLES}-clean over 8000 s: "
+      f"{_starve.episodes} episodes, {_starve_fires} notification(s)")
+check(f"a de-assert does not RESET the notification budget, so repeated chatter "
+      f"cannot starve the alarm to silence ({_starve_fires} notifications over "
+      f"8000 s, not 1)",
+      _starve_fires > 10)
+
 # --- THE HYSTERESIS, PINNED AGAINST THE CHATTER DIRECTION --------------------
 # ⚠️ REVIEW-FOUND. This used to issue `range(CLEAR_CYCLES - 1)` clean cycles,
 # which at CLEAR_CYCLES = 1 issues ZERO of them and passes while printing
@@ -898,6 +1000,105 @@ check("...and main.py:856's consumer is the line that goes quietly false",
       bool(ctl_w.clamp_last and ctl_w.clamp_last.engaged))
 
 
+# --------------------------------------------------------------------------- #
+# 6d. SAFETY-38 round 4 - THE ORDERED PAIR INSIDE `ClampResult.describe()`
+# --------------------------------------------------------------------------- #
+# ⚠️ THIS IS THE ALARM THE OWNER HAS BEEN COMPLAINING ABOUT ALL DAY, AND UNTIL
+# THIS BLOCK NO test_*.py MENTIONED `describe()` AT ALL. `clamp.py:253` builds
+# the whole §15 action-log row and the whole ClampWatchdog notification reason
+# out of its own attributes:
+#
+#     f"{REASON_CODE}: the computed setpoint {self.requested_w:+.0f} W was
+#       clamped to {self.applied_w:+.0f} W by the {self.bound} bound
+#       (rating {self.limit_w:.0f} W) - something upstream is winding"
+#
+# Transpose `requested_w` and `applied_w` and the guard reports clamping a
+# setpoint UPWARD - here, to +9999 W by a bound whose rating the SAME SENTENCE
+# gives as 2000 W. MEASURED on this tree: a zero-byte edit (22 507 bytes before,
+# 22 507 after, sha256 0153133741497fa5 -> 47e4e371043e3201), the emitted
+# sentence changes, and the full 21-file suite stayed GREEN. Nothing decides on
+# the order, so nothing behavioural can ever see it - which is why the check
+# below has to be on the ORDERED PAIR and on the CONTIGUOUS LITERAL. A substring
+# test for either number passes under the swap; both numbers are still there.
+#
+# ⚠️ AND THE OPERANDS ARE READ OFF THE PLANT, NOT OFF `clamp_last`. `ctl.target`
+# is what the loop asked for and `hass.writes[-1]` is what the device was
+# actually sent; neither is a `ClampResult` field. Grading the sentence against
+# `result.requested_w` would compare the swap against itself - DEV-02's defect,
+# and the same one that made the first cut of this card's own render probe emit
+# thirteen empty diffs.
+
+
+async def _sentence(max_w, dev, wanted):
+    """One real write over `max_w`, then the guard, on a real Controller."""
+    hass = _Hass(0.0)
+    c = Controller({"setpoint_entity": "number.sp", "meter_source": "off",
+                    "max_w": max_w},
+                   hass, _Store(), _Pub(), stop=asyncio.Event())
+    c.auto = True
+    c.dev_min, c.dev_max = -dev, dev
+    c.target = wanted
+    arm(c, wanted)
+    await c.write_setpoint(wanted)
+    await c.check_output_clamp()
+    return hass, c
+
+
+hass_x, ctl_x = _sentence_run = asyncio.run(_sentence(2000.0, 5000.0, 9999.0))
+notes_x = clamp_notes(hass_x)
+_asked_x = ctl_x.target                  # what the loop asked for
+_sent_x = hass_x.writes[-1]              # what the device was actually sent
+_rating_x = ctl_x.inverters[0].max_w     # the bound the sentence names
+_rows_x = [e for e in ctl_x.events if REASON_CODE in e]
+print(f"    max_w {_rating_x:.0f} on a +-5000 W device, asked for "
+      f"{_asked_x:+.0f} W: the device saw {_sent_x:+.0f} W")
+print(f"       action log: {_rows_x[0] if _rows_x else '(none)'}")
+check("PRECONDITION: the write really clamped on the MAX_W bound, and the two "
+      "operands are DIFFERENT NUMBERS that RENDER differently - equal ones "
+      "would make the transposed sentence identical and every check below "
+      "vacuous. The asked-for magnitude is also strictly ABOVE the rating "
+      "while the sent one is not, which is what makes the swapped sentence "
+      "self-contradictory rather than merely wrong",
+      ctl_x.clamp_last is not None and ctl_x.clamp_last.engaged
+      and ctl_x.clamp_last.bound == "max_w"
+      and _asked_x != _sent_x
+      and f"{_asked_x:+.0f}" != f"{_sent_x:+.0f}"
+      and abs(_sent_x) <= _rating_x < abs(_asked_x))
+check("⚠️ THE ORDERED PAIR IN THE §15 ACTION-LOG ROW (main.py:1366). The "
+      "contiguous literal names the setpoint the loop COMPUTED first and the "
+      "one that REACHED THE WIRE second. Under the transposition this row says "
+      "the loop asked for +2000 W and the guard clamped it UP to +9999 W - "
+      "past the 2000 W rating printed four words later - which is the alarm "
+      "reading backwards on the one line an operator is woken by",
+      any(f"the computed setpoint {_asked_x:+.0f} W was clamped to "
+          f"{_sent_x:+.0f} W" in e for e in _rows_x))
+check("⚠️ ...AND IN THE ClampWatchdog NOTIFICATION REASON (main.py:2452), "
+      "which is a SECOND surface off the same sentence and has to be pinned "
+      "separately - SAFETY-38 round 3's whole lesson was that pinning one call "
+      "site leaves the other shipping",
+      bool(notes_x)
+      and f"the computed setpoint {_asked_x:+.0f} W was clamped to "
+          f"{_sent_x:+.0f} W" in notes_x[0]["message"])
+check("...and the TRANSPOSED sentence appears on NEITHER surface, so the two "
+      "checks above discriminate rather than decorate",
+      not any(f"the computed setpoint {_sent_x:+.0f} W was clamped to "
+              f"{_asked_x:+.0f} W" in e for e in _rows_x)
+      and f"the computed setpoint {_sent_x:+.0f} W was clamped to "
+          f"{_asked_x:+.0f} W" not in notes_x[0]["message"])
+# The DEVICE bound, off part 6c's controller: same sentence, other stage. The
+# unit of coverage is the call site, and `bound` is the only thing that differs
+# between the two rows an operator can receive.
+_asked_w, _sent_w = ctl_w.target, hass_w.writes[-1]
+check("...and the same ordered pair holds on the DEVICE-bound row, where the "
+      "loop asked for +3000 W and the device took +2500 W. PRECONDITION: those "
+      "two also render differently",
+      f"{_asked_w:+.0f}" != f"{_sent_w:+.0f}"
+      and any(f"the computed setpoint {_asked_w:+.0f} W was clamped to "
+              f"{_sent_w:+.0f} W" in e for e in ctl_w.events)
+      and f"the computed setpoint {_asked_w:+.0f} W was clamped to "
+          f"{_sent_w:+.0f} W" in notes_w[0]["message"])
+
+
 # ==============================================================================
 print()
 print("7. SAFETY-28: the write path is gated on the allocation record")

goodwe_controller/test_control.py

@@ -17,9 +17,20 @@ Read MUTATION.md before you report a survivor.
 
 import sys
 
-from app.control import Tuning, compute, maintenance_charge_floor, peak_at_risk
+from app.control import (LOOP_TICK_S, PLANT_SETTLE_DOWN_S, PLANT_SETTLE_S,
+                         SETTLE_CYCLES, SLEW_RAIL_FRAC, Tuning, compute,
+                         slew_limit_w, unasked_power,
+                         maintenance_charge_floor, peak_at_risk)
 
-T = Tuning()
+# ⚠️ SAFETY-39: `slew_w` IS EXPLICIT HERE NOW, AND IT IS release/1.0's VALUE.
+# `Tuning()`'s default became 0 - "follow the rail", `SLEW_RAIL_FRAC * max_w`,
+# 222 W against this 2000 W rail - so a bare `Tuning()` here would silently
+# re-tune every assertion below that the slew limit touches, and several of them
+# assert on a number the slew produces. The pair written here (max_w 2000,
+# slew_w 1000) is exactly what release/1.0 shipped, which is what most of this
+# file is a regression test against. The new default gets its own section at the
+# end, where it is the subject rather than a hidden parameter.
+T = Tuning(slew_w=1000.0)
 fails = []
 
 
@@ -49,6 +60,41 @@ def check(name, cond):
 # A comment cannot go stale-green, because it never claims to be running.
 #
 # Measured at 389d9ec. Numbers are the lead's independent reproduction.
+# ⚠️ THE SAFETY-13 ROWS WERE RE-MEASURED IN ROUND 2 AND THREE OF THEM WERE
+# WRONG AS FIRST WRITTEN. Every figure below marked (S13) was taken by deleting
+# the mechanism, purging __pycache__, running this file in the CI image and
+# counting `FAIL` lines, on THIS tree; the release/1.0 comparison figures were
+# taken the same way on a pristine c8dcb38 worktree.
+#
+#   - `output freeze` was written as 11. The mutation form its own note
+#     describes - the whole `target = min(...)/max(...)` line removed, `reason`
+#     left alone - gives 6 on this tree AND 6 on the first SAFETY-13 commit,
+#     against 2 on release/1.0. 11 is not reproducible by that form, or by
+#     removing the line and its `reason` (4), or by swapping min/max (12). The
+#     row is 6.
+#   - `saturation detector, saturated_now = False` was left at 11 while the
+#     SAFETY-13 section added checks that grade it. It is 15.
+#   - the footnote's `frozen = False` figure was left at 10 for the same
+#     reason. It is 13.
+#
+# The rows below `output freeze` are this ticket's own mechanisms: removing the
+# EXIT restores release/1.0's unbounded freeze; making `unasked_power()` return
+# True gives an exit to the limit case as well, which is the half of the
+# decision that has to stay unbounded; deriving SETTLE_CYCLES from
+# PLANT_SETTLE_S (18 s, the UP ramp) instead of PLANT_SETTLE_DOWN_S (23 s) is
+# the round-1 defect itself; and pinning `_SAT_COUNT_CAP` back at release/1.0's
+# literal 10 caps the counter below the bound and deletes the exit silently.
+#
+# ⚠️ ONLY THE ROWS THIS BRANCH MOVES WERE RE-MEASURED. Everything not marked
+# (S13) still carries 389d9ec's figures and was not re-run here.
+#
+# ⚠️ THE SLEW ROWS WERE RE-MEASURED AT SAFETY-39 AND ONE OF THEM MOVED: the
+# slew limit was 4 and is now 5, because the SAFETY-39 section grades it too.
+# The new row is the RAIL DEFAULT specifically - `slew_limit_w()` reduced to
+# `return abs(float(tuning.slew_w))`, which leaves the limit intact and only
+# removes the 0-means-the-rail resolution. Three checks notice, which is over
+# the invariant's floor of two. Both figures were reproduced by deleting the
+# mechanism, running this file and counting, on a tree with __pycache__ purged.
 #
 #   mechanism in compute()                     checks that fail when deleted
 #   ------------------------------------------ -----------------------------
@@ -56,11 +102,16 @@ def check(name, cond):
 #   integrator clamp (AC 1)                                                6
 #   integrator bound follows max_w                                         4
 #   output clamp                                                           3
-#   slew limit                                                             4
-#   output freeze                                                          2
+#   slew limit                                                             5
+#   slew follows the rail (SAFETY-39), `slew_w` read raw                   3
+#   output freeze                                        (S13)             6
+#   the output freeze's EXIT (S13), freeze made unconditional again        4
+#   `unasked_power()` discriminates, replaced by `return True`  (S13)      6
+#   SETTLE_CYCLES from PLANT_SETTLE_S, not _DOWN_S        (S13)            9
+#   `_SAT_COUNT_CAP` pinned back at release/1.0's 10      (S13)            6
 #   deadband                                                               5
 #   quantisation                                                           2
-#   saturation detector, `saturated_now = False`                          11
+#   saturation detector, `saturated_now = False`         (S13)            15
 #   saturation duration (AC 2), fires instantly                            2
 #   sat counter reset on a good cycle                                      6
 #   target_grid_w bias                                                     3
@@ -68,7 +119,8 @@ def check(name, cond):
 #
 # The detector figure is for the `saturated_now = False` form specifically;
 # disabling it further down as `frozen = False` is a weaker mutation and gives
-# 10. Reproduce the same form or the number will not match.
+# 13 on this tree (10 on release/1.0). Reproduce the same form or the number
+# will not match.
 #
 # ⚠️ IT HAS FOUND A DEAD MECHANISM TWICE, BOTH THE SAME WAY: a clamp standing in
 # for the mechanism under test. Deleting the integrator freeze once failed
@@ -264,8 +316,15 @@ check("frozen at i_w=0.0: an export push moves the integrator",
 # hundreds of watts means something else is driving the bus. Asserted so that
 # nobody "fixes" it by accident - the integrator moving is what this ticket
 # owns, the command rule belongs to the output freeze.
+#
+# ⚠️ SAFETY-13 KEPT THIS ASSERTION RATHER THAN INVERTING IT, and the fixture is
+# why it survived unchanged: `sat_count=3` becomes 4, which is below
+# SETTLE_CYCLES, so this is still inside the window in which the block holds.
+# SAFETY-13 gave the block an EXIT, not a different opinion about its first
+# cycles - see the SAFETY-13 section below, where the same state is driven past
+# the bound and the release is asserted on the other side of it.
 check("frozen at i_w=0.0: the output freeze still blocks a charge from 0 W",
-      ze.target_w == 0.0)
+      ze.target_w == 0.0 and ze.sat_count < SETTLE_CYCLES)
 # Where prev_w is already charging the output freeze does NOT block, and there
 # the difference reaches the wire: held at 0.0 the integrator abandons the
 # charge mid-export.
@@ -328,11 +387,360 @@ def unwind(t):
     return prev
 
 
-tight, loose = unwind(Tuning(max_w=2000)), unwind(Tuning(max_w=2000, integrator_max_w=3000))
+# ⚠️ BOTH FIXTURES CARRY release/1.0's `slew_w` EXPLICITLY (SAFETY-39). The
+# subject here is `integrator_max_w`, and the figure the check names - 1000 W on
+# the first cycle after the drop - is `max_w - slew_w`, so it moves with the slew
+# limit and would stop being the number DOCS.md quotes. Pinning it keeps this a
+# test about integrator headroom instead of a test about two mechanisms at once;
+# the shipped default's own unwind is measured in the SAFETY-39 section below.
+tight = unwind(Tuning(max_w=2000, slew_w=1000.0))
+loose = unwind(Tuning(max_w=2000, slew_w=1000.0, integrator_max_w=3000))
 check(f"after saturation ends the command is {tight:.0f} W (<= 1000)", tight <= 1000)
 check(f"headroom above max_w makes that worse ({loose:.0f} W) - hence the default",
       loose > tight)
 
+print("SAFETY-13: the output freeze has an exit, and only where it needs one")
+
+# THE SHAPE OF THIS SECTION. release/1.0's output freeze holds the command's
+# magnitude down while the inverter is not following, and nothing ends it. At
+# `prev_w == 0` the held magnitude is ZERO, so it reads as "refuses to start a
+# charge"; that is the case the card was written about, but it is one instance
+# of a rule that is unbounded at every prev_w. SAFETY-13 bounds it exactly where
+# it CANNOT end on its own - see `unasked_power()` - and nowhere else.
+
+# --- 1. the predicate, which is the whole of the decision -------------------
+# A limit can only make the inverter do LESS than the command, in the command's
+# own direction, so everything a limit can produce lies in the interval spanned
+# by 0 and prev_w widened by saturation_w. These are the four cases in the
+# docstring, run rather than described.
+check("limit: 700 W under a +2000 W command is explainable",
+      not unasked_power(2000.0, 700.0, 500.0))
+check("limit: -700 W under a -5000 W command is explainable",
+      not unasked_power(-5000.0, -700.0, 500.0))
+check("unasked: +700 W under a 0 W command is not",
+      unasked_power(0.0, 700.0, 500.0))
+check("unasked: +700 W under a -800 W command is not",
+      unasked_power(-800.0, 700.0, 500.0))
+# The band edges belong to the limit side, because saturation_w is the same
+# tolerance the detector uses - a reading the detector calls "following" must
+# never be called "another writer".
+check("the saturation band is inclusive on both edges",
+      not unasked_power(0.0, 500.0, 500.0)
+      and not unasked_power(0.0, -500.0, 500.0)
+      and unasked_power(0.0, 500.01, 500.0))
+# ⚠️ AT prev_w == 0 THE PREDICATE AND THE DETECTOR ARE THE SAME TEST, which is
+# why the zero case is the one that strands: with nothing commanded there is no
+# interval for a limit to live in.
+same = all(unasked_power(0.0, a, 500.0) == (abs(a) > 500.0)
+           for a in [x * 5.0 for x in range(-400, 401)])
+check("at prev_w == 0 unasked_power IS the saturation test, over 801 readings",
+      same)
+
+# --- 2. the bound is derived, and from WHICH HALF of the measurement --------
+# ⚠️ THE DIRECTION IS THE ASSERTION. goodwe/NOTES.md 5.10 measured the same
+# 1.78 kW step both ways: ~18 s up, ~23 s down. SAFETY-39 takes the SHORTER
+# one because its bound is a REFUSAL and the looser number refuses less. This
+# bound asks the opposite question - how long the plant may still be the
+# explanation for a divergence - and for that the conservative half is the
+# LONGER one. The first version of this file derived it from 18, got 9, and
+# that is three cycles short of the plant's own measured down-ramp, in the
+# direction that ACCUSES rather than refuses (section 8 below drives it).
+check(f"SETTLE_CYCLES is ceil(PLANT_SETTLE_DOWN_S / LOOP_TICK_S) ="
+      f" {SETTLE_CYCLES}",
+      SETTLE_CYCLES == 12
+      and SETTLE_CYCLES * LOOP_TICK_S >= PLANT_SETTLE_DOWN_S
+      and (SETTLE_CYCLES - 1) * LOOP_TICK_S < PLANT_SETTLE_DOWN_S)
+check("...from the LONGER of the two measured settle times, so it is strictly"
+      " above what the shorter one would have given",
+      PLANT_SETTLE_DOWN_S > PLANT_SETTLE_S
+      and SETTLE_CYCLES > -(-PLANT_SETTLE_S // LOOP_TICK_S))
+# ...and it is NOT SLEW_RAIL_FRAC's reciprocal any more. It was, while both
+# were being derived from the same half of the pair, and that coincidence read
+# as a derivation. Asserted as an INEQUALITY so the two cannot silently be
+# re-fused into one number again.
+check("the slew's rail crossing and this bound are now different numbers",
+      SETTLE_CYCLES > 1.0 / SLEW_RAIL_FRAC)
+# The counter has to be able to REACH the bound or the exit does not exist.
+# Driven, not read off the constant: run a saturated state and see how high the
+# counter actually goes.
+c, sc = 0, 0
+while c < 50:
+    sc = compute(0.0, -2000.0, 900.0, T, sc).sat_count
+    c += 1
+check(f"the saturation counter reaches {sc}, which is above the bound",
+      sc >= SETTLE_CYCLES)
+
+# --- 3. prev_w == 0: blocked below the bound, released above it -------------
+# The same state either side of the bound. This is the pair the card asks for.
+blk = compute(prev_w=0, grid_w=-2000, actual_w=-600, tuning=T,
+              sat_count=SETTLE_CYCLES - 2, i_w=0.0)
+check("prev_w=0: below the bound the charge is still refused",
+      blk.target_w == 0.0 and blk.reason == "saturated-freeze"
+      and blk.sat_count == SETTLE_CYCLES - 1)
+rel = compute(prev_w=0, grid_w=-2000, actual_w=-600, tuning=T,
+              sat_count=SETTLE_CYCLES - 1, i_w=0.0)
+check(f"prev_w=0: at the bound it is released to {rel.target_w:.0f} W",
+      rel.target_w < 0.0 and rel.reason == "freeze-released"
+      and rel.sat_count == SETTLE_CYCLES)
+# ...and the released command is the SLEW step from 0, not the rail. A release
+# that jumped to the integrator in one cycle would be the windup this ticket
+# was told to avoid.
+check(f"the released command is exactly one slew step"
+      f" ({slew_limit_w(T):.0f} W)",
+      abs(rel.target_w) == slew_limit_w(T))
+# The mirror. Nothing here is sign-specific, so the discharge side must behave
+# identically - every freeze rule in this file has a mirror, because the one
+# that did not is the defect that got through review.
+mblk = compute(prev_w=0, grid_w=2000, actual_w=600, tuning=T,
+               sat_count=SETTLE_CYCLES - 2, i_w=0.0)
+mrel = compute(prev_w=0, grid_w=2000, actual_w=600, tuning=T,
+               sat_count=SETTLE_CYCLES - 1, i_w=0.0)
+check("prev_w=0, discharging: same block, same release, mirrored",
+      mblk.reason == "saturated-freeze" and mrel.reason == "freeze-released"
+      and mrel.target_w == slew_limit_w(T))
+
+# --- 4. non-zero prev_w, and the two halves are NOT the same --------------
+# (a) A divergence a LIMIT could have produced is never released, however long
+# it stands. This is release/1.0's behaviour and it is kept deliberately: the
+# freeze clears itself here, because the command is pinned at something the
+# inverter can do.
+TL = Tuning(max_w=5000.0, slew_w=400.0, target_grid_w=-10.0)
+prev, i_w, sat, reasons = 0.0, 0.0, 0, set()
+for _ in range(30):
+    d = compute(prev, 4000.0, max(-1000.0, min(1000.0, prev)), TL, sat, i_w)
+    prev, i_w, sat, _r = d.target_w, d.i_w, d.sat_count, reasons.add(d.reason)
+check("non-zero prev_w, a curtailed inverter: never released over 30 cycles",
+      "freeze-released" not in reasons and prev == 2400.0)
+# (b) A divergence a limit could NOT have produced is released at the bound,
+# at a non-zero prev_w exactly as at zero. release/1.0 pinned this run at
+# -800 W, against its own integrator standing at -2388 W, for as long as it ran.
+prev, i_w, sat, rows = 0.0, 0.0, 0, []
+for _ in range(20):
+    d = compute(prev, -2000.0, 700.0, TL, sat, i_w)
+    rows.append((prev, d.target_w, d.i_w, d.reason))
+    prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+pinned = [r for r in rows if r[3] == "saturated-freeze"]
+check(f"non-zero prev_w, another writer: pinned at {pinned[0][1]:.0f} W...",
+      pinned and all(r[1] == -800.0 for r in pinned))
+check(f"...then released, settling at {prev:.0f} W", prev == -2390.0)
+
+# --- 5. THE CARD'S OWN CASE, DRIVEN END TO END -----------------------------
+# The live install's shape (max_w 5000, slew_w 400, target_grid_w -10). The site
+# rests in the deadband with another writer holding the pack at +700 W - so the
+# saturation counter climbs while the command is 0 and nothing is wrong - and
+# then 2 kW of export arrives. On release/1.0 @ c8dcb38 the command is 0.0 W on
+# every cycle from there on: 0 W is a FIXED POINT, and the export is given away
+# for as long as the other writer stays.
+prev, i_w, sat, cmds = 0.0, 0.0, 0, []
+for c in range(24):
+    d = compute(prev, -10.0 if c < 6 else -2000.0, 700.0, TL, sat, i_w)
+    cmds.append(d.target_w)
+    prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+check("the card's case: the block does hold at first, at 0 W",
+      cmds[6] == 0.0 and cmds[7] == 0.0)
+started = [i for i, c in enumerate(cmds) if c != 0.0]
+check(f"the card's case: the charge starts at cycle {started[0]}"
+      f" instead of never", bool(started))
+# ⚠️ AND IT STOPS AT THE FROZEN INTEGRATOR, NOT AT THE RAIL. This is AC 4: the
+# integrator moved while the output was blocked, and the release must not turn
+# that divergence into windup. It cannot, because releasing the OUTPUT freeze
+# does not release the INTEGRATOR freeze - so the command can only walk, one
+# slew step per cycle, to a value the integrator stopped accumulating at.
+check(f"the card's case: it settles at {prev:.0f} W, at the frozen integrator "
+      f"({i_w:.0f} W) and not the {TL.max_w:.0f} W rail",
+      prev == -1190.0 and abs(prev) <= abs(i_w) and abs(prev) < TL.max_w)
+steps = [abs(cmds[i] - cmds[i - 1]) for i in range(1, len(cmds))]
+check(f"the card's case: no cycle moves more than the slew limit "
+      f"(worst {max(steps):.0f} W of {slew_limit_w(TL):.0f})",
+      max(steps) <= slew_limit_w(TL))
+
+# --- 6. AC 4, AS A PROPERTY RATHER THAN A TRAJECTORY -----------------------
+# ⚠️ THE FIRST FORM OF THIS CHECK WAS WRONG AND THE SWEEP SAID SO, which is
+# worth leaving in the file. It asserted `|target| <= |i_w|` on a released
+# cycle, and the sweep produced prev_w -5000, i_w -3000, target -4600: the
+# command was walking BACK from -5000 toward the integrator and had not
+# arrived. It was moving the right way and the assertion still failed, because
+# "never exceeds the integrator" is not what no-windup means here.
+#
+# What it means: a released cycle can only move the command TOWARD the
+# integrator, by at most one slew step, and never past it. So the divergence
+# that built up while the output was blocked cannot arrive as a jump - it is
+# spent one slew step at a time, against an integrator that stopped
+# accumulating when the freeze engaged and is not released with the output.
+# ⚠️ AND THE COUNT BELOW IS THE RELEASED STATES, NOT THE SWEPT ONES. The first
+# version of this check named 41*25*21*5 - the size of the sweep - while
+# grading only the subset that actually releases, so the number in the message
+# was not the number the assertion was about. It is counted now.
+step = float(T.step_w)
+swept, past, jumped = 0, [], []
+n_released = 0
+for prev in [x * 250.0 for x in range(-20, 21)]:
+    for grid in [x * 500.0 for x in range(-12, 13)]:
+        for actual in [x * 500.0 for x in range(-10, 11)]:
+            for i0 in (-3000.0, -500.0, 0.0, 500.0, 3000.0):
+                swept += 1
+                d = compute(prev, grid, actual, TL, SETTLE_CYCLES, i0)
+                if d.reason != "freeze-released":
+                    continue
+                n_released += 1
+                lo, hi = min(prev, d.i_w), max(prev, d.i_w)
+                if not (lo - step <= d.target_w <= hi + step):
+                    past.append((prev, grid, actual, i0, d.target_w, d.i_w))
+                if abs(d.target_w - prev) > slew_limit_w(TL) + step:
+                    jumped.append((prev, grid, actual, i0, d.target_w))
+check(f"of {swept} states swept, the {n_released} that release keep the command"
+      f" between the previous command and the frozen integrator"
+      + (f" (e.g. {past[0]})" if past else ""), not past and n_released > 0)
+check("...and no released cycle moves further than one slew step"
+      + (f" (e.g. {jumped[0]})" if jumped else ""), not jumped)
+
+# --- 7. NO ACCEPTED CONFIGURATION CAN DELETE THE BLOCK ---------------------
+# ⚠️ THIS CHECK REPLACES ITS OWN OPPOSITE, AND THE REASON IS WORTH KEEPING.
+# While the bound was 9, `saturation_cycles` - which config.yaml accepts up to
+# 10 - could be set AT OR ABOVE it, and then the freeze did not engage until
+# its own exit was already due: the no-start block silently stopped existing,
+# and this file asserted that as a known consequence. Moving the bound to 12
+# put the whole accepted range strictly below it, so the degenerate
+# configuration is gone rather than documented.
+#
+# It is pinned against config.yaml ITSELF and not a transcription, because the
+# property is "two files agree" and a transcription is what lets them drift.
+# Regex, not PyYAML: the add-on image ships no PyYAML (test_validate.py says
+# the same thing at more length).
+import os                                   # noqa: E402
+import re                                   # noqa: E402
+
+_CFG = os.path.join(os.path.dirname(os.path.abspath(__file__)), "config.yaml")
+with open(_CFG, encoding="utf-8") as _fh:
+    _m = re.search(r"^  saturation_cycles: int\((\d+),(\d+)\)\s*$",
+                   _fh.read(), re.M)
+check("config.yaml's saturation_cycles range really was read", _m is not None)
+_sc_lo, _sc_hi = int(_m.group(1)), int(_m.group(2))
+check(f"every accepted saturation_cycles ({_sc_lo}..{_sc_hi}) is strictly"
+      f" below the bound ({SETTLE_CYCLES}), so no accepted configuration can"
+      f" push the freeze's engagement past its own exit",
+      _sc_hi < SETTLE_CYCLES)
+# Driven at the schema's edge rather than argued: the block still engages, and
+# it engages before the exit is due.
+TN = Tuning(slew_w=1000.0, saturation_cycles=_sc_hi)
+prev, i_w, sat, reasons = 0.0, 0.0, 0, set()
+first_freeze = None
+for _ in range(20):
+    d = compute(prev, -2000.0, 700.0, TN, sat, i_w)
+    reasons.add(d.reason)
+    if d.reason == "saturated-freeze" and first_freeze is None:
+        first_freeze = d.sat_count
+    prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+check(f"at the largest accepted saturation_cycles ({_sc_hi}) the block still"
+      f" engages, at sat_count {first_freeze}, below the bound",
+      "saturated-freeze" in reasons and first_freeze is not None
+      and first_freeze < SETTLE_CYCLES)
+
+# --- 8. THE BOUND'S DIRECTION, DRIVEN ON ONE INVERTER ----------------------
+# ⚠️ WHY THIS SECTION EXISTS. The exit's two conditions are read as "another
+# writer is on the actuator". They are not that, and the first shipped form of
+# this file said they were. `unasked_power()` compares a reading against ONE
+# cycle's command while the pack carries every command before it, so a command
+# that has fallen THROUGH ZERO - or simply fallen faster than the pack coasts -
+# leaves our own power outside our own interval. With the bound derived from
+# the 18 s UP measurement that is not a corner case: it is what a normal load
+# step does.
+#
+# The plant here is a MODEL and is labelled one. It is a first-order lag whose
+# two time constants come from the two measured settling times (a first-order
+# step is 95 % done at 3 tau, so tau = t / 3), with the ramp cap
+# sim/plantsim.py measured on inverter A. It is not the rig and it is not the
+# house; what it is for is that the two settling times ENTER the model in the
+# same direction they enter the constant, so the check moves if either does.
+#
+# ⚠️ AND THERE IS NO SECOND WRITER IN THIS SECTION. One `compute()`, one
+# plant, one command. Every `freeze-released` below is therefore false.
+import math                                 # noqa: E402
+
+
+class _Plant:
+    """One inverter, obeying our command and nothing else. A MODEL."""
+
+    RAMP_W_S = 800.0        # sim/plantsim.py INVERTER_A, measured=True
+
+    def __init__(self, up_s, down_s):
+        self.a_up = 1.0 - math.exp(-LOOP_TICK_S / (up_s / 3.0))
+        self.a_dn = 1.0 - math.exp(-LOOP_TICK_S / (down_s / 3.0))
+        self.w = 0.0
+
+    def tick(self, cmd):
+        a = self.a_up if abs(cmd) > abs(self.w) else self.a_dn
+        cap = self.RAMP_W_S * LOOP_TICK_S
+        self.w += max(-cap, min(cap, a * (cmd - self.w)))
+
+
+from app import control as _control          # noqa: E402
+
+TS8 = Tuning(max_w=5000.0, slew_w=400.0, target_grid_w=-10.0,
+             saturation_w=500.0, saturation_cycles=3)
+
+
+def _drive(bound, load1, load2, cycles=60, switch=25):
+    """Run one closed loop at an arbitrary bound. -> (release cycles, rows)."""
+    was_b, was_c = _control.SETTLE_CYCLES, _control._SAT_COUNT_CAP
+    # ⚠️ BOTH, OR THE PROBE LIES: `_SAT_COUNT_CAP` is what `compute()` caps the
+    # counter with, so moving the bound without it caps the counter BELOW the
+    # bound and the exit quietly becomes unreachable - which reads as "no false
+    # positives". That is the hazard `_SAT_COUNT_CAP`'s own comment names.
+    _control.SETTLE_CYCLES, _control._SAT_COUNT_CAP = bound, bound + 1
+    try:
+        p = _Plant(PLANT_SETTLE_S, PLANT_SETTLE_DOWN_S)
+        prev, i_w, sat, rows = 0.0, 0.0, 0, []
+        for c in range(cycles):
+            load = load1 if c < switch else load2
+            d = compute(prev, load - p.w, p.w, TS8, sat, i_w)
+            rows.append((c, prev, p.w, d.target_w, d.sat_count, d.reason))
+            prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+            p.tick(prev)
+        return [r for r in rows if r[5] == "freeze-released"], rows
+    finally:
+        _control.SETTLE_CYCLES, _control._SAT_COUNT_CAP = was_b, was_c
+
+
+_SHORT = int(-(-PLANT_SETTLE_S // LOOP_TICK_S))       # what 18 s would give: 9
+
+# A 4 kW export falling to 2.5 kW. Nothing exotic; no second writer.
+_bad, _rows = _drive(_SHORT, -4000.0, -2500.0)
+check(f"a bound derived from the SHORTER measurement ({_SHORT} cycles) fires"
+      f" the exit on ONE inverter with nothing else on the bus"
+      + (f" - {len(_bad)} cycle(s), first at cycle {_bad[0][0]}" if _bad else ""),
+      bool(_bad))
+if _bad:
+    _c, _prev, _act, _tgt, _sat, _ = _bad[0]
+    check(f"...and what it called unasked is our own coast-down: command"
+          f" {_prev:.0f} W, pack still at {_act:.1f} W, and the pack was"
+          f" commanded {min(r[1] for r in _rows[:_c]):.0f} W a few cycles"
+          f" earlier",
+          unasked_power(_prev, _act, TS8.saturation_w)
+          and abs(_act) > abs(_prev)
+          and min(r[1] for r in _rows[:_c]) < _act)
+_good, _ = _drive(SETTLE_CYCLES, -4000.0, -2500.0)
+check(f"the shipped bound ({SETTLE_CYCLES} cycles, the LONGER measurement)"
+      f" does not fire on the same run", not _good)
+# ...and not on any of these, either. The whole grid of load steps the same
+# plant can be given, at the tuning every headline figure in this ticket is
+# quoted from.
+_L = [x * 500.0 for x in range(-8, 9)]
+_fired = {}
+for _b in (_SHORT, SETTLE_CYCLES):
+    _fired[_b] = sum(1 for _a in _L for _z in _L
+                     if _a != _z and _drive(_b, _a, _z)[0])
+_pairs = len(_L) * (len(_L) - 1)
+check(f"over {_pairs} load-step pairs on the measured plant, one inverter and"
+      f" no second writer: the short bound fires in {_fired[_SHORT]} of them,"
+      f" the shipped bound in {_fired[SETTLE_CYCLES]}",
+      _fired[SETTLE_CYCLES] < _fired[_SHORT])
+# ⚠️ AND THE SHIPPED FIGURE IS NOT ZERO IN GENERAL. It is small here because
+# the plant in this model is the one that was measured. A plant slower than
+# that brings the false release back, and no constant derived from a
+# measurement can fix that - it is why DOCS.md tells the operator what
+# `freeze-released` is evidence OF, rather than what it proves.
+
 print("SAFETY-04: the i_w=None path is still release/1.0, exactly")
 
 
@@ -369,23 +777,113 @@ def legacy(prev, grid, actual, t, sat_count):
 # "i-clamped", because the truncation happens on the integrator before the
 # command is derived from it. Aliased here rather than papered over - if any
 # OTHER reason ever diverges, this check goes red.
+# ⚠️ SAFETY-13 IS A DELIBERATE DIVERGENCE FROM `legacy()`, AND THE SWEEP NOW
+# GRADES THE DIVERGENCE INSTEAD OF FORBIDDING IT. `legacy()` above stays a
+# transcription of release/1.0 - it is not edited to agree, for the reason the
+# note on `slew_w` gives: an oracle taught the new rule compares the new law
+# against itself. What changed is the assertion. Every case must either be
+# IDENTICAL to release/1.0, or be a case where release/1.0 said
+# "saturated-freeze" and this law says "freeze-released" with the two conditions
+# that permit it both true. Anything else is a regression, and the counts below
+# say how much of the sweep each answer covers.
 ALIAS = {"i-clamped": "clamped"}
+# ⚠️ SAFETY-13 ROUND 2 MOVED THE COUNTER'S CEILING, SO THE SWEEP NOW HAS A
+# THIRD ANSWER. `_SAT_COUNT_CAP` is `SETTLE_CYCLES + 1`, which was 10 - the
+# same literal release/1.0 used - and is now 13. Above release/1.0's own
+# ceiling the two counters therefore differ, and NOTHING ELSE MAY: `frozen` is
+# `sat_count >= saturation_cycles` and config.yaml accepts that at most 10, so
+# a counter reading 13 instead of 10 cannot change it, and no other line in
+# `compute()` reads the counter's value. That is asserted rather than asserted-
+# by-omission, in `cap_diffs` below.
+#
+# ⚠️ AND THE SWEEP HAS TO REACH THE BOUND OR IT GRADES NOTHING. `sc` runs to 12
+# now; at 9 the counter tops out one short of the exit and every release
+# silently disappears from this table, which is exactly what happened when the
+# bound moved and is why the count is asserted and not merely printed. 12 is a
+# state release/1.0 could never hold - its counter stopped at 10 - so
+# `legacy()` is being fed one input outside its own reachable domain, on
+# purpose, and `cap_diffs` is where that shows up.
+LEGACY_SAT_CAP = 10             # release/1.0's literal, transcribed in legacy()
 diffs = []
+released = []
+value_diffs = []
+cap_diffs = []
 seen = set()
-for tune in (Tuning(), Tuning(target_grid_w=-10.0), Tuning(max_w=5000, slew_w=5000)):
+# ⚠️ `slew_w` IS WRITTEN OUT IN ALL THREE (SAFETY-39). `legacy()` below is a
+# TRANSCRIPTION of release/1.0 and reads `t.slew_w` directly, as release/1.0
+# did; the new law reads `slew_limit_w(t)`, which treats 0 as 'follow the
+# rail'. The two agree for every non-zero value and differ at 0 BY DESIGN, so
+# a fixture that left the field at its new default would report the design as
+# a regression. Fixing it in `legacy()` instead would make this sweep compare
+# the new law against itself, which is the one thing it must never do.
+for tune in (Tuning(slew_w=1000.0), Tuning(slew_w=1000.0, target_grid_w=-10.0),
+             Tuning(max_w=5000, slew_w=5000)):
     for prev in (-2000.0, -500.0, -100.0, 0.0, 100.0, 500.0, 2000.0):
         for grid in (-6000.0, -1000.0, -500.0, -14.0, 0.0, 14.0, 500.0, 1000.0, 6000.0):
             for actual in (-2000.0, 0.0, 600.0, 2000.0):
-                for sc in (0, 2, 3, 9):
+                for sc in (0, 2, 3, 9, 12):
                     d = compute(prev, grid, actual, tune, sc)   # i_w defaults to None
                     seen.add(d.reason)
                     got = (d.target_w, d.sat_count, d.frozen,
                            ALIAS.get(d.reason, d.reason))
-                    if got != legacy(prev, grid, actual, tune, sc):
-                        diffs.append((prev, grid, actual, sc, got,
-                                      legacy(prev, grid, actual, tune, sc)))
-check(f"i_w=None reproduces release/1.0 over {3*7*9*4*4} cases, reason included"
-      + (f" (first diff {diffs[0]})" if diffs else ""), not diffs)
+                    was = legacy(prev, grid, actual, tune, sc)
+                    if got == was:
+                        continue
+                    # everything that reaches the wire, without the counter
+                    wire_same = (got[0], got[2], got[3]) == (was[0], was[2], was[3])
+                    if wire_same:
+                        # the ceiling moved and nothing else did. Only legal
+                        # above release/1.0's own cap, and only with both
+                        # counters standing at their own ceilings.
+                        if (sc >= LEGACY_SAT_CAP
+                                and was[1] == LEGACY_SAT_CAP
+                                and got[1] == _control._SAT_COUNT_CAP):
+                            cap_diffs.append((prev, grid, actual, sc, got[1], was[1]))
+                            continue
+                        diffs.append((prev, grid, actual, sc, got, was))
+                        continue
+                    explained = (
+                        d.reason == "freeze-released"
+                        and was[3] == "saturated-freeze"
+                        and d.sat_count >= SETTLE_CYCLES
+                        and unasked_power(prev, actual, tune.saturation_w))
+                    if not explained:
+                        diffs.append((prev, grid, actual, sc, got, was))
+                        continue
+                    released.append((prev, grid, actual, sc))
+                    if got[0] != was[0]:
+                        value_diffs.append((prev, got[0], was[0]))
+TOTAL = 3 * 7 * 9 * 4 * 5
+check(f"i_w=None reproduces release/1.0 over {TOTAL} cases except where"
+      f" SAFETY-13 releases the freeze, reason included"
+      + (f" (first unexplained diff {diffs[0]})" if diffs else ""), not diffs)
+# ⚠️ EXACT COUNTS, NOT INEQUALITIES. A weaker form of this line ("some
+# releases happened") was written while the bound was moving, and the coverage
+# audit caught it immediately: a `unasked_power()` that stops discriminating
+# went from 6 checks to 5. The three numbers partition the sweep, so any one of
+# them moving is a change somebody has to explain.
+check(f"{TOTAL - len(released) - len(cap_diffs)} of {TOTAL} cases are"
+      f" bit-identical to release/1.0; {len(released)} are releases;"
+      f" {len(cap_diffs)} differ in the saturation counter alone",
+      len(released) == 432 and len(cap_diffs) == 81
+      and TOTAL - len(released) - len(cap_diffs) == 3267)
+# ⚠️ THE COUNTER-ONLY DIFFERENCES ARE NOT A LOOPHOLE, so they are pinned twice:
+# they may only occur at an `sc` above release/1.0's ceiling, and the largest
+# `saturation_cycles` config.yaml accepts is below BOTH ceilings, so no
+# accepted configuration can see the difference at all.
+check(f"the {len(cap_diffs)} counter-only differences all sit above"
+      f" release/1.0's cap of {LEGACY_SAT_CAP}, where no accepted"
+      f" saturation_cycles can read them",
+      all(r[3] >= LEGACY_SAT_CAP for r in cap_diffs) and _sc_hi <= LEGACY_SAT_CAP)
+# ⚠️ AND THE RELEASES ARE MOSTLY A LABEL. Only these change what reaches the
+# wire; the rest report "freeze-released" on a command the freeze was not
+# binding on anyway. Every one of them is a charge that release/1.0 refused to
+# start from exactly 0 W, which is the ticket, stated as a count.
+check(f"{len(value_diffs)} of those {len(released)} change the command,"
+      f" and every one is a charge start from prev_w == 0 that was refused",
+      len(value_diffs) == 27
+      and all(p == 0.0 and new_ < 0.0 and old_ == 0.0
+              for p, new_, old_ in value_diffs))
 
 # ...and the rename is not a quiet deletion: the signal SAFETY-03 alarms on has
 # to actually occur in that sweep, or its hook is dead.
@@ -443,6 +941,205 @@ check("worst billed rest point falls from 15 W to under 5 W",
       compute(500.0, 4.9, 500.0, TB).reason == "deadband"
       and compute(500.0, 5.0, 500.0, TB).reason != "deadband")
 
+print("SAFETY-39: the slew limit is a RATIO to the rail, not a number")
+# ⚠️ WHAT WENT WRONG, IN ONE LINE, BECAUSE THE SHAPE IS THE POINT. `slew_w:
+# 1000` was derived on 2026-08-22 against a clamp of 1500 W and its stated
+# justification was that it caps "how far the loop can jump ahead of the
+# inverter". The live install then ran max_w 5000 with the same 1000, and on
+# 2026-09-05 11:43-11:46 a real 3.4 kW export drove the setpoint 380 -> 5000 W
+# in five 2 s ticks, the battery to -5154 W against a 5000 VA inverter, and the
+# grid from 3.4 kW of EXPORT to 2.8 kW of IMPORT. Nothing was broken. The rail
+# moved and the constant did not.
+#
+# So what is graded below is the RELATIONSHIP and not a value: at every rail,
+# the loop takes the plant's own settling time to cross its whole output range.
+# A check that pinned "555 W" would go stale the same way the comment did.
+print(f"    SLEW_RAIL_FRAC = LOOP_TICK_S / PLANT_SETTLE_S = {SLEW_RAIL_FRAC:.4f}"
+      f"  ({1 / SLEW_RAIL_FRAC:.0f} ticks to cross the rail)")
+check("0 means FOLLOW THE RAIL and resolves to SLEW_RAIL_FRAC * max_w",
+      slew_limit_w(Tuning(max_w=5000.0, slew_w=0.0)) == SLEW_RAIL_FRAC * 5000.0)
+check("an explicit value is passed through untouched - it is the operator's "
+      "number and nothing here silently reduces it",
+      slew_limit_w(Tuning(max_w=5000.0, slew_w=400.0)) == 400.0)
+check("the shipped Tuning default is 0, i.e. the rail, so the law carries no "
+      "second constant to go stale beside config.yaml",
+      Tuning().slew_w == 0.0)
+
+# ⭐ THE RELATIONSHIP ITSELF, over every rail this add-on can be built at: the
+# single-inverter schema range (100..5000), the live install (5000), and the
+# roster sums a second inverter produces - 9600 with inverter B's datasheet
+# figure, 10000 with two of A. ⚠️ 9600 IS NOT A MEASUREMENT: inverter B does not
+# exist on site yet (SPIKE-04, ~2026-09-12) and 4600 W is its datasheet and
+# serial, per goodwe/NOTES.md §1.1b. It is here because the ARITHMETIC is what
+# is being graded, and the arithmetic does not care.
+_rails = [100.0, 500.0, 1500.0, 2000.0, 5000.0, 9600.0, 10000.0]
+_ticks = {r: r / slew_limit_w(Tuning(max_w=r)) for r in _rails}
+print("    ticks to cross the rail at the default, by rail: "
+      + ", ".join(f"{r:.0f}W={t:.1f}" for r, t in _ticks.items()))
+check("⭐ AT EVERY RAIL THE DEFAULT TAKES THE SAME NUMBER OF TICKS TO CROSS IT - "
+      "which is PLANT_SETTLE_S at the measured tick. This is the whole of "
+      "SAFETY-39: raising max_w moves the slew limit with it, so the constant "
+      "cannot be left behind by the rail again",
+      all(abs(t - PLANT_SETTLE_S / LOOP_TICK_S) < 1e-9 for t in _ticks.values()))
+check("...and that is the same as saying the crossing takes the plant's own "
+      f"measured settling time ({PLANT_SETTLE_S:.0f} s) at the "
+      f"{LOOP_TICK_S:.0f} s tick the live install was measured running",
+      all(abs(t * LOOP_TICK_S - PLANT_SETTLE_S) < 1e-9 for t in _ticks.values()))
+
+# ⭐ VERIFIED BY BREAKING IT. The configuration that produced the 2026-09-05
+# excursion, put through the same arithmetic: it crosses the rail in 10 s
+# against a plant that takes 18 s. This is the number validate.py rule 10
+# refuses on, and it is asserted HERE too so that the law and the gate cannot
+# drift apart - the rule can only ever refuse what this ratio says is too fast.
+_broken = Tuning(max_w=5000.0, slew_w=1000.0)
+_broken_s = 5000.0 / slew_limit_w(_broken) * LOOP_TICK_S
+print(f"    the 2026-09-05 configuration (max_w 5000, slew_w 1000) crosses its "
+      f"rail in {_broken_s:.0f} s against a plant measured at {PLANT_SETTLE_S:.0f} s")
+check("⭐ RESTORING slew_w 1000 AT max_w 5000 IS FASTER THAN THE PLANT, and by "
+      "the ratio rather than by anybody's opinion - test_validate.py's rule 10 "
+      "section refuses exactly this pair",
+      _broken_s < PLANT_SETTLE_S
+      and slew_limit_w(_broken) > SLEW_RAIL_FRAC * _broken.max_w)
+
+# THE CLOSED LOOP, AND WHAT THIS PLANT IS AND IS NOT.
+#
+# ⚠️ THE PLANT BELOW IS MODELLED HERE AND IS NOT THE RIG. admin/goodwe's
+# `plantsim.Plant` is the battery model this project grades control changes
+# against, and this repository's CI cannot reach it - that repository is private
+# and this job's token is minted for this one (see .gitea/workflows/checks.yml).
+# So the rig evidence lives in `tools/slew_sim.py`, is quoted in the pull
+# request and in DECISIONS/SAFETY-39-slew-against-the-rail.md, and what runs
+# HERE is a first-order lag with the time constant that reproduces §5.10's
+# measured ~18 s to the deadband. test_alloc.py makes the same split for the
+# same reason and says so in the same words.
+#
+# ⚠️ AND IT CANNOT SHOW A BATTERY ABOVE ITS RATING, WHICH IS SAID BEFORE THE
+# RESULT RATHER THAN AFTER IT. Neither this model nor `plantsim.Plant` lets the
+# plant exceed `p_max`; both clamp. The -5154 W against a 5000 VA inverter that
+# the ticket reports is therefore NOT REPRODUCIBLE IN SIMULATION AT ALL, by
+# construction, and no acceptance criterion here is written on it. What IS
+# reproducible, and is what is graded, is the loop OVER-ABSORBING and driving
+# the meter from export into import - the error it then chases.
+_TAU_S = 6.0            # first-order lag; with the 2 s tick it reaches the
+                        # deadband ~18 s after a step, which is §5.10's figure
+
+
+def _step_run(tuning, export_w, load_w=350.0, phase=5, cycles=90,
+              dt=LOOP_TICK_S):
+    """One export step onto a converged loop.
+
+    -> (worst import at the meter, peak battery beyond what the site NEEDED,
+        largest setpoint change in one tick).
+    """
+    import math
+    prev, i_w, sat, actual, pv = 0.0, None, 0, 0.0, 0.0
+    a = 1.0 - math.exp(-dt / _TAU_S)
+    worst_import, peak, biggest, last = -1e9, 0.0, 0.0, None
+    for c in range(cycles):
+        if c == phase:
+            pv = export_w + load_w
+        grid = load_w - pv - actual
+        d = compute(prev, grid, actual, tuning, sat, i_w)
+        if c >= phase and last is not None:
+            biggest = max(biggest, abs(d.target_w - last))
+        last = d.target_w
+        prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+        # the plant: a first-order lag, clamped at the rating like the real one
+        actual += (max(-tuning.max_w, min(tuning.max_w, prev)) - actual) * a
+        if c >= phase:
+            worst_import = max(worst_import, load_w - pv - actual)
+            peak = max(peak, abs(actual))
+    return worst_import, peak - export_w, biggest
+
+
+def _family(tuning):
+    """The worst case over 51 export steps, 1.0-4.2 kW, at three phases.
+
+    ⚠️ A FAMILY AND NOT ONE STEP, AND THAT IS A FINDING RATHER THAN CAUTION.
+    A single run of this loop is not evidence: the deadband, the 10 W
+    quantisation and the phase of the step against the tick move the result by
+    hundreds of watts, non-monotonically, so two adjacent slews can rank either
+    way on one step and the opposite way on the next. Every number below is a
+    worst case over the family, which is how admin/goodwe grades the same
+    quantities (see `config.yaml`'s "1890 closed-loop runs" and "924 runs").
+    """
+    worst = dict(imp=-1e9, over=-1e9, step=0.0, big=0, runs=0)
+    for export_w in range(1000, 4300, 200):
+        for phase in (5, 6, 7):
+            imp, over, step = _step_run(tuning, float(export_w), phase=phase)
+            worst["runs"] += 1
+            worst["imp"] = max(worst["imp"], imp)
+            worst["over"] = max(worst["over"], over)
+            worst["step"] = max(worst["step"], step)
+            worst["big"] += step >= 900.0
+    return worst
+
+
+_LIVE = Tuning(max_w=5000.0, slew_w=1000.0)      # what ran on 2026-09-05
+_RAIL = Tuning(max_w=5000.0)                     # slew_w 0 - follow the rail
+_INTERIM = Tuning(max_w=5000.0, slew_w=400.0)    # applied live 2026-09-05 12:00
+_SLOWER = Tuning(max_w=5000.0, slew_w=250.0)
+_GAIN03 = Tuning(max_w=5000.0, gain=0.3)
+_GAIN02 = Tuning(max_w=5000.0, gain=0.2)
+_R = {k: _family(t) for k, t in
+      (("live", _LIVE), ("rail", _RAIL), ("interim", _INTERIM),
+       ("slower", _SLOWER), ("gain03", _GAIN03), ("gain02", _GAIN02))}
+print(f"    worst case over {_R['live']['runs']} export steps at max_w 5000, "
+      f"{LOOP_TICK_S:.0f} s tick:")
+for _k, _lab in (("live", "gain 0.6  slew_w 1000  (the 2026-09-05 live pair)"),
+                 ("rail", "gain 0.6  slew_w 0     (follow the rail)"),
+                 ("interim", "gain 0.6  slew_w 400   (the live interim)"),
+                 ("slower", "gain 0.6  slew_w 250"),
+                 ("gain03", "gain 0.3  slew_w 0"),
+                 ("gain02", "gain 0.2  slew_w 0")):
+    _w = _R[_k]
+    print(f"      {_lab:<48} largest tick step {_w['step']:5.0f} W, "
+          f"{_w['big']:2}/{_w['runs']} runs step >= 900 W, "
+          f"over-absorbed {_w['over']:5.0f} W, meter driven to {_w['imp']:+6.0f} W")
+
+# ⭐ THE DEFECT, REPRODUCED BEFORE ANYTHING IS CHANGED. The live pair steps the
+# setpoint by a full 1000 W on nearly every member of the family and drives the
+# meter from EXPORT into IMPORT - the loop manufacturing the error it then
+# chases. That is the 2026-09-05 observation and it is what makes this a control
+# fault rather than a slow loop.
+check("⭐ REPRODUCED: at max_w 5000 with slew_w 1000 the setpoint steps a full "
+      "1000 W per tick on nearly every step in the family, and the meter is "
+      "driven from export into import",
+      _R["live"]["step"] >= 900.0
+      and _R["live"]["big"] > 0.9 * _R["live"]["runs"]
+      and _R["live"]["imp"] > 200.0)
+check("⭐ FIXED, ON THE THING THE SLEW ACTUALLY OWNS: following the rail removes "
+      "the >= 900 W step from EVERY member of the family - which is the symptom "
+      "that escalated 2 -> 1 -> 13 -> 43 per 30 min on the morning of the "
+      "2026-09-05 excursion",
+      _R["live"]["big"] > 0 and _R["rail"]["big"] == 0
+      and _R["interim"]["big"] == 0)
+
+# ⚠️ AND WHAT IT DOES NOT BUY, MEASURED, ASSERTED, AND SAID BEFORE ANYBODY CAN
+# READ MORE INTO THIS CARD THAN IT DELIVERED. `slew_w` bounds the OUTPUT; the
+# integrator accumulates `gain * error` per cycle and is bounded only by
+# `integrator_max_w`. At gain 0.6 into a 3.4 kW error the integrator moves
+# ~2000 W per tick and reaches a 5000 W rail in under three ticks WHATEVER
+# `slew_w` is. So the over-absorption is a GAIN term, and slowing the slew does
+# not reduce it - on this model it gets slightly WORSE, because the command
+# spends longer away from where it needs to be while the integrator keeps
+# winding. admin/goodwe's rig, a different plant model, agrees: over-absorption
+# 990 W at slew 1000 and 1086 W at slew 250, against 1010 W at gain 0.6 and
+# 863 W at gain 0.3 (tools/slew_sim.py).
+#
+# `gain` is therefore the next constant to re-derive. SAFETY-39 measured it and
+# CHANGED NOTHING: it is a live control-law constant on a running house, and two
+# of them moving in one release makes the next measurement uninterpretable.
+check("⚠️ THE SLEW DOES NOT OWN THE OVER-ABSORPTION, AND THIS CHECK IS HERE SO "
+      "THAT NOBODY READS SAFETY-39 AS 'THE OVERSHOOT IS FIXED'. Quartering the "
+      "slew from 1000 to 250 does not reduce the over-absorption at all",
+      _R["slower"]["over"] >= _R["live"]["over"])
+check("...while the GAIN does own it: 0.6 -> 0.3 -> 0.2 falls monotonically, at "
+      "the same slew. That is the measurement behind 'gain is the next constant "
+      "to re-derive', and it is a measurement rather than an opinion",
+      _R["gain03"]["over"] < _R["rail"]["over"]
+      and _R["gain02"]["over"] < _R["gain03"]["over"])
+
 print()
 if fails:
     print(f"{len(fails)} FAILED: {', '.join(fails)}")

goodwe_controller/test_freeze.py

@@ -144,9 +144,17 @@ def check(name, cond):
         fails.append(name)
 
 
-def tuning(max_w=LIVE_INSTALL_MAX_W):
-    """The shipped defaults from config.yaml, at the live install's max_w."""
-    return Tuning(gain=0.6, max_w=max_w, slew_w=1000, deadband_w=15,
+def tuning(max_w=LIVE_INSTALL_MAX_W, slew_w=0):
+    """The shipped defaults from config.yaml, at the live install's max_w.
+
+    ⚠️ `slew_w` IS 0 - "FOLLOW THE RAIL" - AND IS A PARAMETER (SAFETY-39). 0 is
+    what config.yaml ships and resolves to `SLEW_RAIL_FRAC * max_w`, so it moves
+    with `max_w` instead of being a number typed beside it. It has to be
+    overridable because one case below picks an ABSURDLY SMALL rail on purpose,
+    and at that rail a rail-following slew is 2 W per cycle - which would make
+    the slew, rather than the thing under test, the reason nothing fires.
+    """
+    return Tuning(gain=0.6, max_w=max_w, slew_w=slew_w, deadband_w=15,
                   target_grid_w=-10, step_w=10, saturation_w=500,
                   saturation_cycles=3)
 
@@ -327,10 +335,10 @@ check("the capture loaded", len(rows) > 1000)
 # covers both kWh registers, so a real `unchanged_s` on this data can only be
 # SHORTER than what is reconstructed here - this replay is the pessimistic
 # version of the converged case, not a flattering one.
-def replay(hold_s, max_w, cycle_floor_s=15.0):
+def replay(hold_s, max_w, cycle_floor_s=15.0, slew_w=0):
     """Drive the real control law and the real detector over the capture."""
     wd = FreezeWatchdog(FreezeWatchdogConfig(hold_s=hold_s))
-    t = tuning(max_w)
+    t = tuning(max_w, slew_w)
     target, i_w, sat = 0.0, 0.0, 0
     prev_pwr, changed_at = None, rows[0]["t"]
     last_cycle = None
@@ -456,7 +464,15 @@ check("...and the shipped law really does park the command there",
 # converged capture is silent" is satisfied by a detector that is wired to
 # nothing. Drop the hold to 1 s and the rail to nothing, and the SAME replay
 # must alarm - so the silence above is the data's doing, not the harness's.
-wd_hot, _, _, fired_hot = replay(1.0, 20.0)
+# ⚠️ AND THE SLEW IS PINNED FOR THIS CASE ONLY, WHICH IS THE OTHER HALF OF
+# MAKING BOTH TERMS REACHABLE (SAFETY-39). The rail here is 20 W, chosen absurdly
+# small so the rail term cannot be what holds the alarm off. At the shipped
+# `slew_w: 0` the limit follows that rail too - `SLEW_RAIL_FRAC * 20` is 2.2 W
+# per cycle - so the command could not reach 19 W inside the capture and the
+# replay would go silent for a reason that has nothing to do with the detector.
+# That is exactly the vacuous pass this case exists to rule out, arriving
+# through the case itself, so the slew is written out here and nowhere else.
+wd_hot, _, _, fired_hot = replay(1.0, 20.0, slew_w=20.0)
 check("...and the same replay DOES alarm once both terms are made reachable",
       fired_hot is not None and wd_hot.episodes > 0)
 
@@ -699,7 +715,7 @@ def _opts(**over):
     o = {"setpoint_entity": "number.sp", "meter_entity": "sensor.grid",
          "soc_entity": "sensor.soc", "batt_entity": "sensor.batt",
          "meter_source": "off", "max_w": LIVE_INSTALL_MAX_W, "gain": 0.6,
-         "slew_w": 1000, "deadband_w": SHIPPED_DEADBAND_W,
+         "slew_w": 0, "deadband_w": SHIPPED_DEADBAND_W,
          "target_grid_w": -10, "step_w": 10, "heartbeat_s": 10,
          "stale_input_s": STALE_INPUT_S}
     o.update(over)

goodwe_controller/test_freshness.py

@@ -0,0 +1,879 @@
+"""Runnable check for SAFETY-37's freshness policy.  `python3 test_freshness.py`
+
+THE SUBJECT OF THIS FILE IS THE FIXTURE, NOT THE CODE. A pack legitimately
+resting at 40 % and a dead sensor reading 40 % ARE THE SAME NUMBER. A check that
+cannot separate "fresh and unchanged" from "stale" cannot see the failure it
+names, and this repository has recorded that defect - "a check whose DATA cannot
+reach the failure it names" - eleven times. So part 1 builds the separation and
+ASSERTS THE VALUE STREAMS ARE BIT-IDENTICAL across the pair; everything after it
+is downstream of that pair being real.
+
+⚠️ AND THE CARD'S WORDING HAD TO BE SHARPENED TO BUILD IT, WHICH IS SAID HERE
+RATHER THAN QUIETLY WORKED AROUND. The card says "only arrival separates them".
+For a signal this add-on polls out of Home Assistant's state cache, ARRIVAL
+CANNOT SEPARATE THEM: `read_inputs()` runs about once a second and Home
+Assistant answers 200 with a number whether or not the publisher behind the
+entity is alive, so both members of the pair arrive, identically, forever.
+Part 1a demonstrates exactly that - an arrival-age gate is graded and FAILS to
+tell the pair apart - and it is the reason the shipped verdict is a conjunction
+with an OBLIGATION term rather than an age threshold. Every clock in that
+verdict is still an arrival clock: nothing reads a Home Assistant timestamp,
+which is the half of "arrival-stamped" that TEL-06 is blocked on and that this
+module does honour.
+
+  1.  THE PAIR. Fresh-and-unchanged vs stale, on identical value streams, on
+      the policy object itself. Plus 1a, the arrival-age gate that cannot.
+  2.  THE WIRING. The same pair driven through the REAL `Controller.read_inputs`
+      at a roster of TWO, with the two units carrying DIFFERENT power values.
+  3.  THE CONSUMERS REFUSE, and the counterfactual is run beside them: the
+      per-unit sign check and the circulating-power sensor, with the gate and
+      with the gate removed, through real `cycle()` calls.
+  4.  THE LATCH, and the ~1 Hz oscillation it exists to prevent.
+  5.  N=1. Nothing changes on a healthy install - asserted on the shipped read
+      path, not assumed - and the one thing that DOES change is named.
+  6.  THE BOUNDS, graded against the shipped `config.yaml` at both ends.
+  7.  THE POLICY TABLE tells the truth about what is wired.
+  8.  THE MEASUREMENT the bound rests on, replayed from the committed capture.
+  9.  KNOWN SURVIVORS, graded so they are residuals rather than surprises.
+
+⚠️ INVERTER B DOES NOT PHYSICALLY EXIST (~2026-09-12; goodwe/NOTES.md §1.1b).
+Every two-unit case below is two copies of inverter A's behaviour with
+DIFFERENT numbers passed in, and no number here is a measured parameter for a
+second device.
+
+⚠️ MUTATING THE MODULE THIS FILE GRADES? PURGE `__pycache__` FIRST - or run
+`tools/mutation_run.sh`, which does. `python3 -B` alone does NOT save you: it
+stops bytecode being WRITTEN, not a stale one being READ. Read MUTATION.md
+before you report a survivor.
+"""
+
+import ast
+import asyncio
+import glob
+import gzip
+import io
+import json
+import sys
+import time
+from datetime import datetime, timezone
+from pathlib import Path
+
+from app import freshness as F
+from app.circulation import circulating_w
+from app.freshness import BOUNDS, BATT_OBLIGED_S, BATT_UNCHANGED_S, MOVE_W, Freshness
+from app.inverter import Inverter
+from app.main import Controller
+from app.store import DEFAULTS
+from app.watchdog import SignWatchdog, SignWatchdogConfig, disagrees
+
+fails = []
+HERE = Path(__file__).resolve().parent
+
+
+def check(name, cond):
+    print(f"  {'ok  ' if cond else 'FAIL'} {name}")
+    if not cond:
+        fails.append(name)
+
+
+def run(coro):
+    return asyncio.new_event_loop().run_until_complete(coro)
+
+
+# --------------------------------------------------------------------------- #
+# fixtures
+# --------------------------------------------------------------------------- #
+class MemStore:
+    def __init__(self, data=None):
+        self.data = dict(DEFAULTS, **(data or {}))
+
+    def set(self, k, v):
+        self.data[k] = v
+
+    def get_time(self, *a):
+        return None
+
+    def set_time(self, *a):
+        pass
+
+
+class Pub:
+    enabled = False
+
+    def publish(self, *a, **k):
+        pass
+
+    def close(self):
+        pass
+
+
+class Hass:
+    """A Home Assistant that answers per ENTITY and RECORDS what it served.
+
+    ⚠️ PER ENTITY, AND THE RECORD IS LOAD-BEARING. A stub that answered one
+    number whatever it was asked could not tell "B was read from B's sensor"
+    from "B was handed A's reading" - and the served-value log is what lets
+    part 1 assert that the fresh run and the stale run saw the SAME numbers.
+    """
+
+    def __init__(self, numbers=None, limits=None):
+        self.numbers = dict(numbers or {})
+        self.limits_by = dict(limits or {})
+        self.served = []            # (entity, value) in call order
+        self.writes = []
+
+    async def number(self, entity, invert=False):
+        v = self.numbers.get(entity)
+        self.served.append((entity, v))
+        return None if v is None else (-v if invert else v)
+
+    async def limits(self, entity):
+        return self.limits_by.get(entity, (None, None, None))
+
+    async def set_number(self, entity, value):
+        self.writes.append((entity, value))
+        return True
+
+    async def call(self, domain, service, data):
+        return True
+
+
+A_RATING = 5000.0
+# ⚠️ ILLUSTRATIVE, AND NOT B'S DATASHEET FIGURES. SPIKE-04a established B as a
+# GW5048D-ES rated 4600 W with a 10 % floor (goodwe/NOTES.md §1.1b), and this
+# fixture deliberately does not use them: 5000/4600 is a 400 W gap, narrower
+# than a slew step, and two equal-ish numbers cannot show a check that read the
+# wrong unit's. Same reasoning as test_inverter.py's `B_RATING_HYPOTHESIS`.
+B_RATING_SIM = 3000.0
+A_FLOOR, B_FLOOR_SIM = 10, 15
+
+ROSTER = [
+    {"name": "inverter-a", "setpoint_entity": "number.sp_a",
+     "soc_entity": "sensor.soc_a", "batt_entity": "sensor.batt_a",
+     "max_w": A_RATING, "bms_soc_floor": A_FLOOR},
+    {"name": "inverter-b", "setpoint_entity": "number.sp_b",
+     "soc_entity": "sensor.soc_b", "batt_entity": "sensor.batt_b",
+     "max_w": B_RATING_SIM, "bms_soc_floor": B_FLOOR_SIM},
+]
+
+# ⚠️ A AND B CARRY DIFFERENT POWER VALUES IN EVERY FIXTURE BELOW, and the card
+# names this as the trap it expects: "if both read the same, the test cannot
+# distinguish a frozen reading from a live one and will pass against the broken
+# code". SAFETY-30's fix round walked into exactly that with two watchdog holds
+# both set to 1.
+A_FROZEN_W = -1200.0        # inverter A's register, stuck on a charge figure
+B_LIVE_W = 900.0            # inverter B's register, moving, and NOT A's number
+
+BASE = dict(meter_source="off", meter_entity="sensor.grid", setpoint_entity="",
+            soc_entity="", batt_entity="", max_w=A_RATING, gain=0.6, slew_w=0,
+            deadband_w=15, target_grid_w=0, step_w=10, heartbeat_s=10,
+            stale_input_s=15, inverters=ROSTER)
+
+
+def site(opts=None, numbers=None):
+    """A real two-inverter Controller off the shipped `build_roster()`."""
+    hass = Hass(dict({"sensor.grid": 0.0,
+                      "sensor.soc_a": 50.0, "sensor.batt_a": A_FROZEN_W,
+                      "sensor.soc_b": 55.0, "sensor.batt_b": B_LIVE_W},
+                     **(numbers or {})),
+                {"number.sp_a": (-A_RATING, A_RATING, 1.0),
+                 "number.sp_b": (-B_RATING_SIM, B_RATING_SIM, 1.0)})
+    c = Controller(dict(BASE, **(opts or {})), hass, MemStore(), Pub(),
+                   stop=asyncio.Event())
+    c.inverters[0].dev_min, c.inverters[0].dev_max = -A_RATING, A_RATING
+    c.inverters[1].dev_min, c.inverters[1].dev_max = -B_RATING_SIM, B_RATING_SIM
+    return c, hass
+
+
+# ==============================================================================
+print()
+print("1. THE PAIR: 'fresh and unchanged' vs 'stale', on IDENTICAL value streams")
+
+# The two runs below feed the policy object the SAME forty readings of the same
+# number at the same instants. The ONLY difference is what the controller was
+# asking the inverter to do while those readings arrived.
+#
+#   FRESH   the site is converged. The command sits where it is, the register
+#           answers the same watt, and nothing is wrong. This is the case the
+#           30-day capture in part 8 measures at up to 263.2 s.
+#   STALE   the site reversed. The command travelled 2500 W and the register did
+#           not move by one watt in 40 s, which is 2.4x the fastest it could
+#           possibly be obliged to answer in.
+STREAM = [(float(t), A_FROZEN_W) for t in range(0, 40)]
+
+
+def drive(bound, stream, standing_of):
+    """Feed a Freshness one arrival per (t, value). Returns (obj, served, verdicts)."""
+    f = Freshness(bound)
+    served, verdicts = [], []
+    for t, v in stream:
+        f.submit(v, standing_of(t), t)
+        served.append(v)
+        verdicts.append(f.reading())
+    return f, served, verdicts
+
+
+_fresh, _fresh_served, _fresh_read = drive(
+    BOUNDS["batt"], STREAM, lambda t: A_FROZEN_W)
+# The command travels from -1200 W to +1300 W at t=1 and stays there: a site
+# turnaround, which is the ordinary stimulus SAFETY-31's own campaign sweeps.
+_stale, _stale_served, _stale_read = drive(
+    BOUNDS["batt"], STREAM, lambda t: A_FROZEN_W if t < 1 else 1300.0)
+
+print(f"    served (both runs): {_fresh_served[:3]} ... x{len(_fresh_served)}")
+# ⚠️ `key=str`, AND IT IS NOT COSMETIC. Without it this line raises TypeError
+# comparing None with a float the moment a mutation makes the FRESH run stale -
+# which is what M2 (dropping the command-travel term) did: the file died on a
+# DIAGNOSTIC PRINT before check one, so the harness reported "red" with no named
+# check behind it. MUTATION.md's reporting rule is "which suite went red, and on
+# WHICH NAMED CHECK"; a print that can crash first destroys exactly that.
+print(f"    fresh  verdicts: unique={sorted(set(_fresh_read), key=str)}")
+print(f"    stale  verdicts: first None at t="
+      f"{next((i for i, v in enumerate(_stale_read) if v is None), None)}")
+
+check("⚠️ THE FIXTURE'S OWN PRECONDITION: the two runs saw a BIT-IDENTICAL "
+      "value stream. If this ever stops being true the pair below is comparing "
+      "two different experiments and proves nothing about freshness",
+      _fresh_served == _stale_served
+      and len({v for v in _fresh_served}) == 1)
+check("FRESH AND UNCHANGED is not stale. Forty identical readings over 39 s "
+      "with the command standing still - a converged site - and the reading "
+      "reaches its consumers untouched",
+      not _fresh.stale and _fresh_read == [A_FROZEN_W] * len(STREAM))
+check("⚠️ STALE IS. The same forty readings, the same instants, the same "
+      "numbers - and the command moved 2500 W underneath them. The reading "
+      "becomes None to its consumers, which is the whole card",
+      _stale.stale and _stale_read[-1] is None)
+check("...and it becomes None at the BOUND, not before: 35.0 s of unchanged "
+      "arrivals, so the last fresh verdict is at t=34 and the first None at "
+      "t=35",
+      _stale_read[34] == A_FROZEN_W and _stale_read[35] is None
+      and BATT_UNCHANGED_S == 35.0)
+check("...and NEVER a held number and never a zero - `reading()` has exactly "
+      "two shapes, the arrived value or None",
+      set(type(v) for v in _stale_read) == {float, type(None)}
+      and 0.0 not in [v for v in _stale_read if v is not None])
+check("...and the reason names the three terms an operator has to check, with "
+      "the numbers that fired it",
+      "STALE_READING" in _stale.reason and "2500 W" in _stale.reason
+      and "unchanged for 35 s" in _stale.reason)
+
+# --- 1a. the gate the card asked for first, graded and found unable ----------
+# An arrival-age gate is what "arrival-stamped" reads as on first hearing. It is
+# built here and run against the SAME pair, because a criterion that cannot be
+# satisfied is worth more said out loud than approximated in silence.
+_arrival_ages = []
+_af = Freshness(BOUNDS["batt"])
+for t, v in STREAM:
+    _af.submit(v, A_FROZEN_W, t)
+    # Every read produced a number, so on both members of the pair the age
+    # since the last ARRIVAL is 0.0 at every instant. There is nothing to
+    # threshold.
+    _arrival_ages.append(0.0 if _af.last is not None else None)
+check("⚠️ AN ARRIVAL-AGE GATE CANNOT TELL THE PAIR APART, and that is why the "
+      "shipped verdict is not one. Home Assistant answered every read with a "
+      "number in BOTH runs, so the age since arrival is 0.0 s at every instant "
+      "of both - a threshold on it is a threshold that can never fire, which "
+      "is TEL-06's defect rebuilt in this repository",
+      set(_arrival_ages) == {0.0} and _af.arrivals == len(STREAM))
+check("...while the arrival record IS what the shipped verdict is measured on: "
+      "`unchanged_s` is the gap between arrivals that carried different "
+      "numbers, on this process's own monotonic clock, and no Home Assistant "
+      "timestamp is read anywhere in the module",
+      _stale.unchanged_s(39.0) == 39.0
+      and "last_updated" not in io.open(HERE / "app" / "freshness.py",
+                                        encoding="utf-8").read().split(
+                                            '"""', 2)[2])
+check("...and a read that produced NOTHING is still an immediate None, exactly "
+      "as it is today - a failed read is not an arrival and is not an age",
+      Freshness(BOUNDS["batt"]).reading() is None
+      and (lambda f: (f.submit(5.0, 0.0, 0.0), f.submit(None, 0.0, 1.0),
+                      f.reading() is None and f.held == 5.0)[-1])(
+          Freshness(BOUNDS["batt"])))
+
+
+# ==============================================================================
+print()
+print("2. THE WIRING: the same pair through the REAL read path, at a roster of 2")
+
+
+async def _reads(c, hass, plan):
+    """Drive real `read_inputs()` calls. `plan` is (t, standing_a, batt_a)."""
+    out = []
+    for t, standing_a, batt_a in plan:
+        hass.numbers["sensor.batt_a"] = batt_a
+        # `last_write` is what the write path sets and what `standing_w()`
+        # reads; setting it here is standing in for a write, not for the gate.
+        c.inverters[0].last_write = standing_a
+        await c.read_inputs(now_mono=t)
+        out.append((t, c.inverters[0].batt, c.inverters[1].batt))
+    return out
+
+
+_PLAN_FRESH = [(float(t), A_FROZEN_W, A_FROZEN_W) for t in range(0, 40)]
+_PLAN_STALE = [(float(t), A_FROZEN_W if t < 1 else 1300.0, A_FROZEN_W)
+               for t in range(0, 40)]
+
+_cf, _hf = site()
+_of = run(_reads(_cf, _hf, _PLAN_FRESH))
+_cs, _hs = site()
+_os = run(_reads(_cs, _hs, _PLAN_STALE))
+
+print(f"    fresh run: A={sorted({r[1] for r in _of})}  B={sorted({r[2] for r in _of})}")
+print(f"    stale run: A={sorted({r[1] for r in _os}, key=str)}  "
+      f"B={sorted({r[2] for r in _os})}")
+
+check("PRECONDITION: both runs were served the same per-entity numbers, so the "
+      "difference below is the wiring and not the stimulus",
+      [x for x in _hf.served if x[0] == "sensor.batt_a"]
+      == [x for x in _hs.served if x[0] == "sensor.batt_a"])
+check("⚠️ THE TWO UNITS CARRY DIFFERENT POWER VALUES - A at -1200 W, B at "
+      "+900 W. A fixture whose units read the same number cannot show a gate "
+      "that answered for the wrong unit, which is the trap the card names",
+      A_FROZEN_W != B_LIVE_W and all(r[2] == B_LIVE_W for r in _of))
+check("THROUGH THE REAL PATH: a converged site keeps its reading",
+      all(r[1] == A_FROZEN_W for r in _of))
+check("⚠️ THROUGH THE REAL PATH: a frozen register becomes `Inverter.batt is "
+      "None`. Not a held number, not a zero - the same None a missing entity "
+      "produces, which is the state §11.1 rule 1 already answers with 0 W",
+      _os[34][1] == A_FROZEN_W and _os[35][1] is None
+      and all(r[1] is None for r in _os[35:]))
+check("...and ONLY the frozen unit's. B's own reading is untouched, which is "
+      "the per-unit half: a freshness verdict about A is not evidence about B",
+      all(r[2] == B_LIVE_W for r in _os) and _cs.inverters[1].batt == B_LIVE_W
+      and not _cs.inverters[1].batt_fresh.stale)
+check("...and `inputs_ok` goes False, so the site stops rather than regulating "
+      "against a number nobody measured",
+      _cs.inputs_ok is False and _cf.inputs_ok is True)
+check("...and the operator gets a line saying which unit and why, on the same "
+      "status list the liveness notes use",
+      any("STALE_READING" in n and "inverter-a" in n
+          for n in _cs.liveness_notes())
+      and _cf.liveness_notes() == [])
+check("...and the raw number is still recorded for diagnostics, so the "
+      "operator can see WHAT it was stuck on",
+      _cs.inverters[0].batt_fresh.last == A_FROZEN_W)
+
+
+# ==============================================================================
+print()
+print("3. THE CONSUMERS REFUSE - and the counterfactual runs beside them")
+
+# Both consumers already do the right thing with a None. Neither could ever
+# receive one before this card, which is the entire exposure: the gate is the
+# thing that was missing BETWEEN the shipped read and the shipped check.
+_cfg3 = SignWatchdogConfig(min_w=250.0, hold_s=85.0)
+check("PRECONDITION on the shipped predicate: a None measurement does not "
+      "disagree with anything, so it CLEARS the sign window",
+      disagrees(1300.0, None, True, _cfg3) is False
+      and disagrees(1300.0, A_FROZEN_W, True, _cfg3) is True)
+check("PRECONDITION on the shipped sensor: a roster with a missing term is "
+      "None, and None clears the circulation window rather than accumulating",
+      circulating_w([1300.0, None]) is None
+      and circulating_w([A_FROZEN_W, B_LIVE_W]) == 2 * min(
+          abs(A_FROZEN_W), abs(B_LIVE_W)))
+
+
+async def _cycles(gated, ticks=25, step_mono=12.0, wall=0.20):
+    """Real cycles at N=2 with A's register frozen and the LOOP driving.
+
+    ⚠️ THE COMMAND TRAVEL IS PRODUCED BY THE SHIPPED CONTROL LAW, NOT BY THE
+    FIXTURE. The meter is pinned at +3000 W of import, so `compute()` ramps the
+    site into discharge at its own slew rate through the real allocator and the
+    real write path; nothing here assigns `last_write`. A fixture that set the
+    standing command by hand would be feeding the gate its own arming condition,
+    which is the shape of check this repository keeps finding.
+
+    `gated=False` is THE COUNTERFACTUAL - the shipped behaviour before this
+    card, rebuilt by handing the consumers the raw held number the gate
+    withheld. Same cycles, same stimulus, so the difference between the two
+    columns is the gate and nothing else.
+
+    ⚠️ TWO CLOCKS, DELIBERATELY, AND THE WALL-CLOCK ONE IS THE FLAKE RISK.
+    The freshness verdict runs on the INJECTED monotonic clock (12 s a tick, so
+    the 35 s bound is crossed on tick 3, deterministically, however loaded the
+    machine is). The sign watchdog runs on the WALL clock inside `cycle()`,
+    which cannot be injected - so `unit_sign_disagree_s` is set to 2 s and the
+    ticks are 0.20 s apart, putting the gate's close at ~0.6 s against a 2 s
+    window. That ORDER is the field's - 35 s < 75 s < 85 s by construction, part
+    6 - and the gate is given no head start beyond it.
+
+    ⚠️ AND THE MARGIN IS MEASURED AND ASSERTED RATHER THAN ASSUMED (CI-06).
+    `test_peakguard.py` answered two of its own checks with the wall clock, flaked
+    at ~20 %, and cost a wrong merge diagnosis - a flaky check does not waste a
+    re-run, it manufactures evidence for whichever hypothesis the reader already
+    holds. So this returns the wall clock at which the gate closed, and the check
+    below fails with THAT NUMBER if the box was too slow, rather than reporting a
+    trip that looks like a code defect.
+    """
+    c, hass = site({"unit_sign_disagree_w": 250, "unit_sign_disagree_s": 2,
+                    "sign_disagree_w": 250, "sign_disagree_s": 2,
+                    "site_sign_disagree_w": 250, "site_sign_disagree_s": 2,
+                    "auto_start": True},
+                   {"sensor.grid": 3000.0})
+    c.auto = True
+    circ, tripped_at, standing = [], None, []
+    t_start, t_gate = time.monotonic(), None
+    for k in range(ticks):
+        # A's register is FROZEN on the charge figure it stopped at; B's is
+        # live and is a DIFFERENT number. Neither is touched by the loop.
+        hass.numbers["sensor.batt_a"] = A_FROZEN_W
+        hass.numbers["sensor.batt_b"] = B_LIVE_W
+        await c.read_inputs(now_mono=k * step_mono)
+        if not gated:
+            for inv in c.inverters:
+                inv.batt = inv.batt_fresh.last
+        if t_gate is None and c.inverters[0].batt_fresh.stale:
+            t_gate = time.monotonic() - t_start
+        circ.append(c.site_circulating_w)
+        standing.append(c.inverters[0].standing_w())
+        await c.cycle()
+        if c.inverters[0].sign_wd.tripped and tripped_at is None:
+            tripped_at = k
+        await asyncio.sleep(wall)
+    return c, circ, tripped_at, standing, t_gate
+
+
+_cg, _circg, _tripg, _standg, _tgate = run(_cycles(True))
+_cu, _circu, _tripu, _standu, _ = run(_cycles(False))
+_WD_S = 2.0     # `unit_sign_disagree_s` as this fixture sets it, above
+print(f"    standing on A (gated): {[round(v) for v in _standg]}")
+print(f"    gated      : sign trip tick={_tripg}  circ={_circg[:6]}...")
+print(f"    gate closed after {_tgate:.2f} s of WALL clock, against the "
+      f"{_WD_S:.0f} s watchdog window ({_WD_S / _tgate:.1f}x margin)")
+print(f"    counterfact: sign trip tick={_tripu}  circ={_circu[:6]}...")
+
+check("⚠️ PRECONDITION ON THE WALL CLOCK, AND IT IS A CHECK RATHER THAN AN "
+      "ASSUMPTION (CI-06). The gate closes on the INJECTED clock, the watchdog "
+      "on the real one, so this fixture only means something while the gate "
+      f"closes well inside the window: it closed at {_tgate:.2f} s against "
+      f"{_WD_S:.0f} s. If this fails the machine was slow, not the code - and "
+      "saying so here is what stops that being read as a defect",
+      _tgate is not None and _tgate < 0.5 * _WD_S)
+check("PRECONDITION: the SHIPPED control law really did travel the command - "
+      "the gate's arming term is produced by `compute()` and the allocator, "
+      "not written into the fixture",
+      max(abs(v) for v in _standu) > MOVE_W
+      and abs(_standu[3] - _standu[0]) > MOVE_W)
+
+check("⚠️ COUNTERFACTUAL FIRST - the stimulus is REAL. Without the gate, the "
+      "frozen register false-trips SAFETY-30's per-unit sign check and parks a "
+      "healthy inverter. That is the fault this card was filed for",
+      _tripu is not None and _cu.inverters[0].sign_wd.tripped
+      and "SIGN_DISAGREEMENT" in _cu.inverters[0].sign_wd.reason)
+check("⚠️ AND WITH THE GATE IT DOES NOT TRIP. The reading is withheld before "
+      "the watchdog's window can accumulate, so the check refuses to conclude "
+      "rather than concluding wrongly - which is what a stale reading deserves",
+      _tripg is None and not _cg.inverters[0].sign_wd.tripped)
+check("...and inverter B was not parked either way - the verdict is per unit",
+      not _cg.inverters[1].sign_wd.tripped
+      and not _cu.inverters[1].sign_wd.tripped)
+check("⚠️ COUNTERFACTUAL: without the gate the circulating-power sensor "
+      "reports a loop that is not happening, computed from one frozen term and "
+      "one live one",
+      all(v == 2 * min(abs(A_FROZEN_W), abs(B_LIVE_W)) for v in _circu)
+      and _circu[0] == 1800.0)
+check("⚠️ AND WITH THE GATE IT REPORTS `None` - an unknown, which CLEARS the "
+      "circulation window instead of accumulating it. Both consumers gated, "
+      "from one place, by one mechanism",
+      _circg[0] == 1800.0 and _circg[-1] is None
+      and all(v is None for v in _circg[_circg.index(None):]))
+check("...and the circulation watchdog did not latch on the stale evidence",
+      not _cg.circ_wd.tripped and _cg.circ_wd.over_since is None)
+
+
+# ==============================================================================
+print()
+print("4. THE LATCH, and the ~1 Hz oscillation it exists to prevent")
+
+# Declaring the reading stale makes inputs_ok False, which commands 0 W, which
+# drops the standing command below MOVE_W, which un-arms the conjunction. Without
+# a latch the held number would come straight back to the consumers, and the
+# whole thing would flip once per read for as long as the register stayed dead.
+_lat = Freshness(BOUNDS["batt"])
+for t in range(0, 40):
+    _lat.submit(A_FROZEN_W, A_FROZEN_W if t < 1 else 1300.0, float(t))
+_was = _lat.stale
+_after_zero = []
+for t in range(40, 50):
+    _lat.submit(A_FROZEN_W, 0.0, float(t))       # the site has been stopped
+    _after_zero.append(_lat.reading())
+check("PRECONDITION: it is stale before the site is stopped",
+      _was and _lat.reading() is None)
+check("⚠️ AND IT STAYS STALE ONCE THE SITE COMMANDS 0 W. The conjunction is no "
+      "longer armed - |standing| is 0 W, below the 250 W term - so an unlatched "
+      "verdict would hand the held -1200 W straight back and the site would "
+      "restart into it, then stop, then restart, once per read",
+      all(v is None for v in _after_zero))
+# ⚠️ AND A FAILED READ MUST NOT CLEAR IT EITHER. This check exists because the
+# mutation that added `self.stale = False` to `submit()`'s None branch SURVIVED
+# the whole sweep - no fixture had ever injected a read failure while latched.
+# It matters: a stale verdict stops the site, the site is then commanded 0 W, and
+# a single unreachable-Home-Assistant read would drop the latch into a state
+# where the conjunction is no longer armed - so the held -1200 W would come back
+# to the consumers on the very next successful read.
+_lat_fail = Freshness(BOUNDS["batt"])
+for t in range(0, 40):
+    _lat_fail.submit(A_FROZEN_W, A_FROZEN_W if t < 1 else 1300.0, float(t))
+_lat_fail.submit(None, 0.0, 40.0)                 # Home Assistant did not answer
+_after_fail = _lat_fail.reading()
+_lat_fail.submit(A_FROZEN_W, 0.0, 41.0)           # it answers again, same number,
+                                                  # site now resting at 0 W
+check("⚠️ A FAILED READ DOES NOT CLEAR THE LATCH - found by a SURVIVING "
+      "mutation, not by design. Our inability to fetch a value is not evidence "
+      "that the value moved, and a stale verdict that a single unreachable read "
+      "can drop is one a stopped site would drop every time",
+      _after_fail is None and _lat_fail.stale
+      and _lat_fail.reading() is None)
+
+check("⚠️ AND ONLY MOVEMENT CLEARS IT - a different number arriving, which is "
+      "exactly the evidence the verdict was about. Not a timer, not a restart, "
+      "not the operator's start button",
+      (lambda f: (f.submit(A_FROZEN_W + 1.0, 0.0, 60.0),
+                  (not f.stale) and f.reading() == A_FROZEN_W + 1.0)[-1])(_lat))
+# ⚠️ THE MAGNITUDE TERM OF THE CONJUNCTION, AND THIS CHECK EXISTS BECAUSE A
+# MUTATION SURVIVED WITHOUT IT. Deleting `abs(standing_w) < move_w` from
+# `_grade()` left every other check in this file green, because in all of them a
+# command that has TRAVELLED 250 W has also ENDED UP above 250 W. The case that
+# separates them is a site being brought to REST.
+_rest = Freshness(BOUNDS["batt"])
+# The register reaches +5 W on the same read at which the old +1300 W command is
+# still standing - the write path is serialised, so the register can catch up
+# BEFORE the command settles - and then the site is commanded to 0 W and the
+# register sits at +5 W, correctly, for a minute.
+_rest.submit(1290.0, 1300.0, 0.0)
+_rest.submit(5.0, 1300.0, 1.0)          # standing_at_change captures 1300 W
+for t in range(2, 60):
+    _rest.submit(5.0, 0.0, float(t))    # site at rest; register truthfully +5 W
+check("⚠️ THE MAGNITUDE TERM IS LOAD-BEARING, and it took a surviving mutation "
+      "to show it. A register that reached +5 W while the old +1300 W command "
+      "was still standing has a `standing_at_change` of 1300 W, so the TRAVEL "
+      "term alone reads 1300 W of unfollowed command for the whole minute the "
+      "site rests - and calls a perfectly truthful reading dead. Requiring "
+      "|standing| >= 250 W as well is what says 'a site at rest is not owed "
+      "movement'",
+      not _rest.stale and _rest.reading() == 5.0)
+check("...and the hole that term leaves CANNOT MISLEAD EITHER CONSUMER, which "
+      "is why it is the right trade: a unit commanded under 250 W is one "
+      "`watchdog.disagrees()` is False for whatever the measurement says, and a "
+      "frozen term beside a live unit that is itself resting nets to zero "
+      "circulating power rather than to a false alarm",
+      disagrees(0.0, A_FROZEN_W, True, _cfg3) is False
+      and circulating_w([A_FROZEN_W, 0.0]) == 0.0)
+
+check("...and one watt is enough, because 0x0518 is a 1 W register that "
+      "dithers +/-1 W while holding (goodwe/NOTES.md §5.11, measured "
+      "2026-08-22) - a working register clears this on its next 10 s publish",
+      _lat.held == A_FROZEN_W + 1.0 and not _lat.stale)
+
+
+# ==============================================================================
+print()
+print("5. N=1: nothing changes on a healthy install, and what DOES is named")
+
+_ONE = dict(BASE, inverters=[], setpoint_entity="number.sp_a",
+            soc_entity="sensor.soc_a", batt_entity="sensor.batt_a",
+            bms_soc_floor=A_FLOOR)
+
+
+def one_site():
+    hass = Hass({"sensor.grid": 0.0, "sensor.soc_a": 50.0,
+                 "sensor.batt_a": A_FROZEN_W},
+                {"number.sp_a": (-A_RATING, A_RATING, 1.0)})
+    c = Controller(dict(_ONE), hass, MemStore(), Pub(), stop=asyncio.Event())
+    c.inverters[0].dev_min, c.inverters[0].dev_max = -A_RATING, A_RATING
+    return c, hass
+
+
+async def _one_healthy():
+    c, hass = one_site()
+    seen = []
+    for t in range(0, 60):
+        # A healthy register under a moving command: it dithers, so it is never
+        # the same integer watt twice running.
+        hass.numbers["sensor.batt_a"] = A_FROZEN_W + (t % 3)
+        c.inverters[0].last_write = 1300.0 if t % 2 else -1200.0
+        await c.read_inputs(now_mono=float(t))
+        seen.append(c.inverters[0].batt)
+    return c, seen
+
+
+_c1, _seen1 = run(_one_healthy())
+check("⚠️ AC: AT N=1 NOTHING CHANGES ON A HEALTHY INSTALL, and it is asserted "
+      "rather than assumed. Sixty reads of a dithering register under a command "
+      "reversing every second: every value reaches the consumers unmodified, "
+      "the gate never arms, and the status page says nothing new",
+      _seen1 == [A_FROZEN_W + (t % 3) for t in range(60)]
+      and not _c1.inverters[0].batt_fresh.stale
+      and _c1.liveness_notes() == [] and _c1.inputs_ok is True)
+check("...and the shipped roster really is one unit, so this is the install "
+      "that is running in a house today and not a fixture shaped like it",
+      len(_c1.inverters) == 1 and _c1.inverters[0].name == "inverter-a")
+
+
+async def _one_frozen():
+    c, hass = one_site()
+    for t in range(0, 40):
+        hass.numbers["sensor.batt_a"] = A_FROZEN_W
+        c.inverters[0].last_write = A_FROZEN_W if t < 1 else 1300.0
+        await c.read_inputs(now_mono=float(t))
+    return c
+
+
+_c1f = run(_one_frozen())
+check("⚠️ AND WHAT DOES CHANGE AT N=1 IS NAMED RATHER THAN HIDDEN: a FROZEN "
+      "register now stops the site, where before it read as a healthy "
+      "measurement. That is a behaviour change on the shipped roster and it is "
+      "the point of the card - HW-01 was a one-inverter site, and the pack "
+      "drained to its floor with every detector reading healthy for 6 h 25 m",
+      _c1f.inverters[0].batt is None and _c1f.inputs_ok is False)
+check("...and the direction it fails in is the safe one: a false verdict "
+      "commands 0 W and keeps commanding (§11.1 rule 1), behind the existing "
+      "`stale_input_s` hold, and clears itself on the register's next move",
+      float(_c1f.o.get("stale_input_s")) > 0
+      and _c1f.inverters[0].batt_fresh.stale)
+
+
+# ==============================================================================
+print()
+print("6. THE BOUNDS, graded against the SHIPPED config.yaml at BOTH ends")
+
+
+def option_default(key):
+    """`key`'s default out of config.yaml's `options:` block, at two spaces."""
+    body = io.open(HERE / "config.yaml", encoding="utf-8").read()
+    body = body[body.index("\noptions:"):body.index("\nschema:")]
+    for line in body.splitlines():
+        if line.startswith(f"  {key}:") and not line[2:3].isspace():
+            return float(line.split(":", 1)[1].strip())
+    return None
+
+
+_circ_hold = option_default("circulation_hold_s")
+_unit_hold = option_default("unit_sign_disagree_s")
+_unit_min_w = option_default("unit_sign_disagree_w")
+_ceiling = min(_circ_hold, _unit_hold)
+print(f"    floor  {BATT_OBLIGED_S:.1f} s = settle 6.0 + publish 10.0 + read 1.0")
+print(f"    bound  {BATT_UNCHANGED_S:.1f} s")
+print(f"    ceil   {_ceiling:.1f} s = min(circulation_hold_s {_circ_hold:.0f}, "
+      f"unit_sign_disagree_s {_unit_hold:.0f})")
+
+check("PRECONDITION: both consumer windows were actually found in config.yaml, "
+      "so a rename cannot turn this part into a check of two Nones",
+      _circ_hold == 75.0 and _unit_hold == 85.0 and _unit_min_w == 250.0)
+check("⚠️ THE BOUND IS AT LEAST 2x THE PHYSICAL FLOOR. Below 17.0 s a healthy "
+      "register has not yet been OBLIGED to answer - 6.0 s of plant "
+      "(NOTES §5.9), one 10 s ESPHome publish (firmware/goodwe-master.yaml:181) "
+      "and one 1 s add-on read - so a shorter bound trips on a working inverter",
+      BATT_UNCHANGED_S >= 2 * BATT_OBLIGED_S and BATT_OBLIGED_S == 17.0)
+check("⚠️ AND AT MOST HALF THE TIGHTER CONSUMER WINDOW. A gate slower than its "
+      "consumer hands over the frozen number and explains afterwards. THIS IS "
+      "THE CHECK THAT BITES IF AN OPERATOR'S DEFAULT MOVES: drop "
+      "`circulation_hold_s` to 60 in config.yaml and this goes red",
+      BATT_UNCHANGED_S <= 0.5 * _ceiling)
+# ⚠️ THE FIRST DRAFT OF THIS CHECK CLAIMED THE BAND CONTAINED EXACTLY ONE
+# INTEGER AND IT DOES NOT - it contains 34, 35, 36 and 37, and the check went
+# red on its first run and is written the honest way round here. The band is
+# what is derived; the value inside it is a choice, and the only defensible
+# claims about the choice are that it IS inside and that it is not a number
+# borrowed from somewhere else.
+check("...and the admissible band computed from config.yaml is [34.0, 37.5], "
+      "which contains four integers. 35 is a CHOICE inside a DERIVED band, not "
+      "a derived number, and it is deliberately not 30 - which is "
+      "FIRMWARE_INGEST_VETO_S and would read as a borrowed constant - or 60, "
+      "which is round",
+      [n for n in range(0, 200)
+       if 2 * BATT_OBLIGED_S <= n <= 0.5 * _ceiling] == [34, 35, 36, 37]
+      and BATT_UNCHANGED_S not in (30.0, 60.0))
+check("⚠️ AND `MOVE_W` IS PINNED TO config.yaml TOO. It is the largest value "
+      "that still arms the gate everywhere the per-unit sign check can speak; "
+      "raise `unit_sign_disagree_w` and the gate would stop arming in states "
+      "that check still fires in, which this catches",
+      MOVE_W == _unit_min_w)
+check("...and the module's three floor terms are the numbers this repository "
+      "actually carries, not a transcription of them: the ESPHome publish "
+      "interval is read back out of the shipped firmware",
+      "update_interval: 10s" in io.open(
+          HERE.parent / "firmware" / "goodwe-master.yaml",
+          encoding="utf-8").read()
+      and F.PUBLISH_PERIOD_S == 10.0 and F.READ_PERIOD_S == 1.0
+      and F.PLANT_SETTLE_S == 6.0)
+
+
+# ==============================================================================
+print()
+print("7. THE POLICY TABLE tells the truth about what is WIRED")
+
+def bounds_users(key):
+    """Modules that SUBSCRIPT `BOUNDS[key]` in CODE - parsed, not grepped.
+
+    ⚠️ THE FIRST DRAFT GREPPED FOR THE STRING AND ANSWERED WRONG, because both
+    `inverter.py` and `main.py` NAME `BOUNDS["soc"]` in a comment explaining why
+    it is not wired. A text search cannot tell a mention from a use, and this
+    part's whole job is to tell them apart - so it walks the AST instead.
+    """
+    out = []
+    for path in sorted((HERE / "app").glob("*.py")):
+        if path.name == "freshness.py":
+            continue
+        tree = ast.parse(io.open(path, encoding="utf-8").read())
+        for node in ast.walk(tree):
+            if (isinstance(node, ast.Subscript)
+                    and isinstance(node.slice, ast.Constant)
+                    and node.slice.value == key
+                    and ((isinstance(node.value, ast.Name)
+                          and node.value.id == "BOUNDS")
+                         or (isinstance(node.value, ast.Attribute)
+                             and node.value.attr == "BOUNDS"))):
+                out.append(path.name)
+                break
+    return out
+
+
+_uses_batt = bounds_users("batt")
+_uses_soc = bounds_users("soc")
+for _k, _b in BOUNDS.items():
+    print(f"    {_k:5} wired={_b.wired!s:5} unchanged={_b.unchanged_s:>6} "
+          f"move={_b.move_w:>6}  {_b.signal}")
+print(f"    BOUNDS['batt'] subscripted in CODE by: {_uses_batt}")
+print(f"    BOUNDS['soc']  subscripted in CODE by: {_uses_soc or 'nothing'}")
+
+check("⚠️ `wired=True` MEANS SOMETHING CONSUMES IT. A policy table nobody "
+      "checks is a comment; this is the row `batt` claims and the module that "
+      "claims it",
+      BOUNDS["batt"].wired is True and _uses_batt == ["inverter.py"])
+check("⚠️ AND `wired=False` MEANS NOTHING DOES. SoC is TEL-08's and it is "
+      "STATED here rather than wired, because its obligation term is energy "
+      "through the pack and the constant that needs has never been measured on "
+      "this site. A guessed constant would fire on a pack resting at its floor",
+      BOUNDS["soc"].wired is False and _uses_soc == [])
+check("...and the SoC row says what TEL-08 owes, in the row itself, so the "
+      "next reader does not have to reconstruct why it is unwired",
+      "energy" in BOUNDS["soc"].derivation
+      and "153.6 Wh" in BOUNDS["soc"].derivation
+      and "TEL-08" in BOUNDS["soc"].derivation)
+check("...and every wired bound is a real number - an infinite bound is how a "
+      "row silently becomes decorative",
+      all(b.unchanged_s < float("inf") and b.move_w < float("inf")
+          for b in BOUNDS.values() if b.wired))
+
+
+# ==============================================================================
+print()
+print("8. THE MEASUREMENT the bound rests on, replayed from the committed data")
+
+# ⚠️ THIS IS THE PART THAT STOPS THE DERIVATION BECOMING A STORY. The docstring
+# in freshness.py quotes three numbers off this capture; they are recomputed
+# here from the committed files, so a figure that drifts from its evidence goes
+# red instead of being re-quoted forever.
+#
+# ⚠️ AND IT IS THE METER'S REGISTER, NOT 0x0518. No 30-day capture of the
+# inverter's own power exists. What this establishes is the only thing it is
+# used for: that the legitimate unchanged duration of a 1 W power entity in this
+# house is MINUTES, so an unchanged threshold alone has no admissible value.
+_cap = sorted(glob.glob(str(HERE / "scenarios" / "p1-net-30d-2026-08"
+                            / "p1-net-*.jsonl.gz")))
+_runs, _prev = [], None
+_t0 = time.monotonic()
+for _f in _cap:
+    with gzip.open(_f, "rt") as _fh:
+        for _line in _fh:
+            _r = json.loads(_line)
+            _t = datetime.fromisoformat(_r["t"]).timestamp()
+            if _prev is not None:
+                _runs.append((_t - _prev, _pw))
+            _prev, _pw = _t, float(_r["w"])
+_worst = max(_runs)[0] if _runs else 0.0
+_over_bound = sum(1 for d, _ in _runs if d >= BATT_UNCHANGED_S)
+print(f"    {len(_cap)} days, {len(_runs) + 1} samples, "
+      f"{time.monotonic() - _t0:.1f}s to replay")
+print(f"    longest unchanged run {_worst:.1f} s; "
+      f"{_over_bound} runs >= {BATT_UNCHANGED_S:.0f} s")
+
+check("PRECONDITION: the committed capture is all thirty days, so this is not "
+      "a claim about whatever files happened to be present",
+      len(_cap) == 30 and len(_runs) + 1 == 485841)
+check("⚠️ A REAL 1 W POWER ENTITY HELD ONE VALUE FOR 263.2 s WITH NOTHING "
+      "WRONG. That single measurement is why the bound is a conjunction and "
+      "not a threshold: no unchanged threshold under 263 s is free of false "
+      "positives, and 263 s is 3.5x too slow to protect a 75 s consumer",
+      abs(_worst - 263.2) < 0.1 and _worst > _ceiling)
+check("...and the two figures freshness.py's docstring quotes off this capture "
+      "are the ones it produces today",
+      _over_bound == 10
+      and sum(1 for d, _ in _runs if d >= BATT_OBLIGED_S) == 386)
+check("⚠️ AND THE LONG RUNS ARE ALL UNDER AN UNMOVING LOAD, which is what the "
+      "conjunction keys on. The worst one is 263 s of a steady -899 W export - "
+      "a house doing one thing - so a gate that also requires the COMMAND to "
+      "have travelled 250 W is not armed by any of them",
+      max(_runs)[1] == -899.0)
+
+
+# ==============================================================================
+print()
+print("9. KNOWN SURVIVORS - graded, so they are residuals and not surprises")
+
+# ⚠️ THE REPO'S RECURRING DEFECT IS A CHECK WHOSE DATA CANNOT REACH THE FAILURE
+# IT NAMES. The honest end of that habit is to build the mutations this file
+# would NOT see and record them. Each one below is a real hole in the shipped
+# gate, demonstrated rather than described.
+
+# S1. A register pinned by the INVERTER's own limit, not by a fault. If the
+#     device is derating and cannot follow a command that ASKS FOR MORE, the
+#     register can legitimately hold while the command travels.
+_s1 = Freshness(BOUNDS["batt"])
+for t in range(0, 40):
+    _s1.submit(2503.0, 2650.0 if t < 1 else 4600.0, float(t))
+check("⚠️ SURVIVOR 1, FALSE POSITIVE: a saturated or derating inverter pinned "
+      "at 2503 W while the command climbs to 4600 W is declared stale. The "
+      "register is telling the truth and the gate calls it dead",
+      _s1.stale)
+check("...and its SIZE is bounded and its direction is the safe one: the "
+      "verdict is a site stop, behind the `stale_input_s` hold, and the moment "
+      "the command comes back down the register moves and the latch clears. "
+      "Cost = one spurious stop; it cannot drive the battery anywhere",
+      (lambda f: (f.submit(2400.0, 0.0, 60.0), not f.stale)[-1])(_s1))
+
+# S2. A unit whose command never travels 250 W. HW-01's own shape, at a
+#     smaller scale, and the gate is deliberately not armed for it.
+_s2 = Freshness(BOUNDS["batt"])
+for t in range(0, 400):
+    _s2.submit(A_FROZEN_W, -1200.0 if t < 1 else -1400.0, float(t))
+check("⚠️ SURVIVOR 2, MISS: a register frozen under a command that only ever "
+      "moves 200 W is NEVER detected, for 400 s or forever. This is scoped, "
+      "not overlooked - such a unit is one no per-unit sign check can speak "
+      "about (`unit_sign_disagree_w` is 250 W) and one contributing at most "
+      "250 W to a loop whose reporting floor is 700 W",
+      not _s2.stale and _s2.reading() == A_FROZEN_W)
+
+# S3. A register that dithers on dead data. A publisher that keeps republishing
+#     a stale WINDOW of values rather than one value defeats this entirely.
+_s3 = Freshness(BOUNDS["batt"])
+for t in range(0, 400):
+    _s3.submit(A_FROZEN_W + (t % 2), 1300.0, float(t))
+check("⚠️ SURVIVOR 3, MISS, AND IT IS THE LARGEST ONE: a dead publisher whose "
+      "last value happens to ALTERNATE - or a cache replaying two old samples - "
+      "never triggers the unchanged clock at all. This gate detects a value "
+      "that STOPPED; it cannot detect a value that is WRONG. Nothing in this "
+      "add-on can, and TEL-06's arrival stamp inside the firmware is the only "
+      "layer that could",
+      not _s3.stale and _s3.reading() is not None)
+
+# S4. The gate is per unit, so a whole-site publisher failure that freezes both
+#     registers is caught twice rather than missed - recorded because a reader
+#     might expect the opposite.
+_s4a, _s4b = Freshness(BOUNDS["batt"]), Freshness(BOUNDS["batt"])
+for t in range(0, 40):
+    _s4a.submit(A_FROZEN_W, A_FROZEN_W if t < 1 else 1300.0, float(t))
+    _s4b.submit(B_LIVE_W, B_LIVE_W if t < 1 else -1300.0, float(t))
+check("NOT A SURVIVOR, recorded because it looks like one: a publisher failure "
+      "that freezes BOTH registers is caught on both units independently, on "
+      "each unit's own command travel and each unit's own number",
+      _s4a.stale and _s4b.stale and _s4a.held != _s4b.held)
+
+
+print()
+if fails:
+    print(f"{len(fails)} FAILED: {', '.join(fails)}")
+    sys.exit(1)
+print("all checks passed")

goodwe_controller/test_inverter.py

@@ -192,14 +192,40 @@ class Hass:
 
 A_ENT = {"setpoint_entity": "number.sp_a", "soc_entity": "sensor.soc_a",
          "batt_entity": "sensor.batt_a"}
-# ⚠️ A HYPOTHESIS, NOT A MEASUREMENT. Inverter B does not exist; 3000 W is
-# chosen only because it DIFFERS from A's 5000 W, which is what lets a check
-# tell B's number from A's. SPIKE-04 measures the real one.
+# ⚠️ SPIKE-04a (2026-09-04) ESTABLISHED B'S REAL RATING FROM ITS DATASHEET:
+# a GoodWe GW5048D-ES, serial `55048ESU22AW0992`, 4600 W on the battery path
+# (goodwe/NOTES.md §1.1b). THIS FIXTURE DELIBERATELY DOES NOT USE IT. 3000 W is
+# kept because the only property these checks consume is that B's number is
+# UNMISTAKABLY not A's, and the real pair is 5000/4600 - a 400 W gap, narrower
+# than `slew_w` and inside the range where an off-by-one-unit bug and ordinary
+# control arithmetic produce indistinguishable numbers. Collapsing the fixture
+# onto the real values would cost these checks their separating power to buy
+# realism they do not use. So: ILLUSTRATIVE, NOT B'S RATING, and not a
+# placeholder for it either - the placeholder era ended on 2026-09-04.
 B_RATING_HYPOTHESIS = 3000.0
+# SAFETY-32. Each pack's OWN BMS cut-out percent, now a REQUIRED roster key.
+# ⚠️ 10 IS MEASURED (register 0x0560 on the reference GW5000S-BP and the shipped
+# `bms_soc_floor` default); 15 IS SIMULATED - there is no second pack. They
+# DIFFER on purpose: a fixture whose two per-unit numbers are equal cannot show
+# a check that read the wrong unit's, which is MUTATION.md habit 1 and the defect
+# that has now bitten four consecutive cards. Both sit below the shipped
+# `peak_soc_floor` of 20, so rule 8 accepts this roster.
+A_BMS_FLOOR = 10
+B_BMS_FLOOR_SIM = 15
+
 A_RATING = 5000.0
 
+# ⚠️ `slew_w` IS 0 HERE, AND IT USED TO BE 1000 - SAFETY-39, AND THE WAY THIS
+# FIXTURE FOUND OUT IS THE ARGUMENT FOR THE RULE. This dict pairs `slew_w: 1000`
+# with `max_w: 5000` because both were typed when the flat 5000 W install was
+# new, and that pair is EXACTLY the configuration measured on the owner's system
+# on 2026-09-05 driving the meter from 3.4 kW of export to 2.8 kW of import. The
+# fixture was not wrong when it was written and nothing in this file noticed it
+# had become so; validate.py rule 10 refused it the day it existed, which is
+# what a rule about a relationship is for. 0 means "follow the rail"
+# (`control.SLEW_RAIL_FRAC * max_w`) and is what config.yaml ships.
 BASE_OPTS = dict(A_ENT, meter_source="off", meter_entity="sensor.grid",
-                 max_w=A_RATING, gain=0.6, slew_w=1000, deadband_w=15,
+                 max_w=A_RATING, gain=0.6, slew_w=0, deadband_w=15,
                  target_grid_w=0, step_w=10, heartbeat_s=10, stale_input_s=15)
 
 
@@ -1411,13 +1437,16 @@ _TWO_OPTS.pop("batt_entity")
 _TWO_OPTS["inverters"] = [
     dict(name="inverter-a", setpoint_entity="number.sp_a",
          soc_entity="sensor.soc_a", batt_entity="sensor.batt_a",
-         max_w=A_RATING),
+         max_w=A_RATING, bms_soc_floor=A_BMS_FLOOR),
     # ⚠️ 3000 W IS A HYPOTHESIS AND IS MARKED AS ONE WHEREVER IT APPEARS. It is
     # here because it DIFFERS from A's 5000 W, which is the only property any
     # check below uses. SPIKE-04 measures the real device.
+    # ⚠️ AND SO IS ITS 15 % CUT-OUT (SAFETY-32). There is no second pack to read
+    # register 0x0560 off; the value is SIMULATED, and it differs from A's 10 %
+    # for MUTATION.md habit 1's reason and no other.
     dict(name="inverter-b", setpoint_entity="number.sp_b",
          soc_entity="sensor.soc_b", batt_entity="sensor.batt_b",
-         max_w=B_RATING_HYPOTHESIS),
+         max_w=B_RATING_HYPOTHESIS, bms_soc_floor=B_BMS_FLOOR_SIM),
 ]
 _c9, _hass9 = built(_TWO_OPTS)
 print(f"    the roster built from `inverters:` -> {[repr(i) for i in _c9.inverters]}")
@@ -1493,14 +1522,19 @@ _decl9 = dict(ln.strip().lstrip("- ").split(": ", 1)
               for ln in _entry9.splitlines()[1:] if ": " in ln)
 print(f"    the shipped per-entry schema: {_decl9}")
 check("...and the schema half declares it as a LIST OF OBJECTS whose `name`, "
-      "`setpoint_entity` and `max_w` are REQUIRED - no trailing `?` - so the "
-      "Supervisor refuses a half-written entry before the add-on sees it, and "
-      "an entry can never fall back on a sibling's rating because there is no "
-      "entry without one",
-      set(_decl9) == {"name", "setpoint_entity", "max_w", "soc_entity",
-                      "batt_entity", "batt_invert"}
+      "`setpoint_entity`, `max_w` and `bms_soc_floor` are REQUIRED - no "
+      "trailing `?` - so the Supervisor refuses a half-written entry before the "
+      "add-on sees it, and an entry can never fall back on a sibling's rating "
+      "or on a sibling's BMS cut-out because there is no entry without one. "
+      "⚠️ SAFETY-32 ADDED THE FOURTH ONE AS REQUIRED RATHER THAN AS "
+      "`int(0,50)?`, and the difference is the whole of that card: an optional "
+      "per-pack cut-out is a DEFAULTED one, and a default is one number for "
+      "two batteries - the shallower pack protected by the deeper pack's BMS",
+      set(_decl9) == {"name", "setpoint_entity", "max_w", "bms_soc_floor",
+                      "soc_entity", "batt_entity", "batt_invert"}
       and not any(_decl9[k].endswith("?")
-                  for k in ("name", "setpoint_entity", "max_w"))
+                  for k in ("name", "setpoint_entity", "max_w",
+                            "bms_soc_floor"))
       and all(_decl9[k].endswith("?")
               for k in ("soc_entity", "batt_entity", "batt_invert")))
 
@@ -1582,9 +1616,11 @@ check("...and two inverters on two DIFFERENT entities are accepted, because "
       "that is the configuration this card exists for and a validator that "
       "fires on the legitimate case gets switched off",
       validate_startup_config(_opts(setpoint_entity="", inverters=[
-          dict(name="inverter-a", setpoint_entity="number.sp_a", max_w=A_RATING),
+          dict(name="inverter-a", setpoint_entity="number.sp_a", max_w=A_RATING,
+               bms_soc_floor=A_BMS_FLOOR),
           dict(name="inverter-b", setpoint_entity="number.sp_b",
-               max_w=B_RATING_HYPOTHESIS)])) == [])
+               max_w=B_RATING_HYPOTHESIS,
+               bms_soc_floor=B_BMS_FLOOR_SIM)])) == [])
 
 # --- the rest of rule 9 -------------------------------------------------------
 _p_flat = validate_startup_config(_opts(inverters=[
@@ -1875,6 +1911,10 @@ _AUDITED = {
     ("test_maintenance.py", "shipped_default"),
     ("test_maintenance.py", "schema_range"),
     ("test_freeze.py", "_cfg_default"),
+    # SAFETY-37. Found by this very check on its first run - `option_default()`
+    # reads the two consumer windows the freshness bound is derived from, so it
+    # is a key-taking reader and belongs here rather than outside the audit.
+    ("test_freshness.py", "option_default"),
     ("test_price.py", "shipped"),
     ("test_tariff.py", "shipped_option"),
 }

goodwe_controller/test_loop.py

@@ -94,7 +94,7 @@ class _Pub:
 
 BASE = {"setpoint_entity": "number.sp", "meter_entity": "sensor.grid",
         "soc_entity": "sensor.soc", "batt_entity": "sensor.batt",
-        "meter_source": "off", "max_w": 2000, "gain": 0.6, "slew_w": 1000,
+        "meter_source": "off", "max_w": 2000, "gain": 0.6, "slew_w": 0,
         "deadband_w": 15, "target_grid_w": -10, "step_w": 10,
         "heartbeat_s": 10, "stale_input_s": 15}
 

goodwe_controller/test_maintenance.py

@@ -1059,9 +1059,16 @@ class Pub:
         pass
 
 
-# ⚠️ 3000 W FOR PACK B IS A HYPOTHESIS AND IS MARKED AS ONE EVERYWHERE IT
-# APPEARS. Inverter B does not physically exist; the number is here only because
-# it DIFFERS from pack A's 5000 W, which is the only property these checks use.
+# ⚠️ SPIKE-04a (2026-09-04) ESTABLISHED B'S REAL RATING FROM ITS DATASHEET:
+# a GoodWe GW5048D-ES, serial `55048ESU22AW0992`, 4600 W on the battery path
+# (goodwe/NOTES.md §1.1b). THIS FIXTURE DELIBERATELY DOES NOT USE IT. 3000 W is
+# kept because the only property these checks consume is that B's number is
+# UNMISTAKABLY not A's, and the real pair is 5000/4600 - a 400 W gap, narrower
+# than `slew_w` and inside the range where an off-by-one-unit bug and ordinary
+# control arithmetic produce indistinguishable numbers. Collapsing the fixture
+# onto the real values would cost these checks their separating power to buy
+# realism they do not use. So: ILLUSTRATIVE, NOT B'S RATING, and not a
+# placeholder for it either - the placeholder era ended on 2026-09-04.
 B_RATING_HYPOTHESIS = 3000.0
 A_RATING = 5000.0
 FLAT_OPTS = dict(setpoint_entity="number.sp_a", soc_entity="sensor.soc_a",

goodwe_controller/test_mqtt.py

@@ -0,0 +1,800 @@
+"""Runnable check for TEL-07 - the SECOND MQTT device, and A's history.
+`python3 test_mqtt.py`
+
+WHAT THIS FILE IS FOR, in one sentence: to prove by DIFFING THE ANNOUNCED
+PAYLOADS - not by reading the code - that giving inverter B its own MQTT device
+changes nothing about inverter A's.
+
+⚠️ WHY THAT IS THE WHOLE CARD. `app/mqtt.py`'s own note records the finding:
+Home Assistant composes an entity_id from the DEVICE name plus the ENTITY name,
+and `object_id` in the discovery payload did NOT override it (tested on HA
+2026.8). So re-scoping the device renames every entity - and because HA keeps
+the id it composed at FIRST discovery, what a rename actually produces is a NEW
+entity beside a DEAD one. The recorded history stays behind on the old id, and
+every dashboard, template and automation that names it - including the three
+live watchdog automations `goodwe_master_watchdog_held_*` and
+`goodwe_master_parked_at_0_w_*` - goes on pointing at an entity that has quietly
+stopped updating. Nothing errors. That is the failure this file exists to make
+impossible to ship.
+
+⚠️ AND THE TEMPTING DESIGN IS THE DESTRUCTIVE ONE. "One device per inverter" -
+A becomes `inverter-a`, B becomes `inverter-b` - is symmetrical and tidy and is
+exactly the change described above. A KEEPS THE DEVICE IT ALREADY HAS; only B
+gets a new one. Part 8 below writes that tidy version and shows it going red.
+
+THE SHAPE OF THE EVIDENCE. Part 1 records what `release/1.0` actually publishes -
+generated by running THAT commit's module, not transcribed - and every later
+part is a diff against it, reported as `N topics, M missing, C changed, A added`.
+
+  Part 1  The recorded baseline, and the diff at a roster of one and of none.
+  Part 2  `_announce()` publishes EXACTLY `discovery_payloads()` and nothing
+          else, so parts 1 and 3-8 are diffing what goes on the wire.
+  Part 3  A roster of two: A's nine messages byte-identical, eight added.
+  Part 4  Zero overlap between A's entities and B's - topics, unique_ids,
+          object_ids, state topics, and devices.
+  Part 5  Site-scoped sensors stay site-scoped, at every roster length 1-6.
+  Part 6  The composed entity_ids, modelled INDEPENDENTLY of `app/mqtt.py`, and
+          anchored on the one composed id that was verified against the live
+          system (`sensor.goodwe_p1_sample_age`, mqtt.py's own note).
+  Part 7  ⚠️ THE ANNOUNCEMENT AND THE PUBLICATION AGREE, on a real `Controller`,
+          with the two units carrying DIFFERENT numbers - so a swap is visible.
+  Part 8  ⚠️ VERIFIED BY BREAKING IT. Twelve mutations of the shipped module,
+          re-executed from mutated source, each one named with the property it
+          breaks. A property nothing breaks is a property nothing is watching.
+  Part 9  What these checks CANNOT see, enumerated and sized.
+
+⚠️ THE FIXTURE GIVES A AND B DIFFERENT NAMES, DIFFERENT RATINGS, DIFFERENT SoC,
+DIFFERENT BATTERY POWER AND DIFFERENT LATCH STATES, ON PURPOSE. A fixture whose
+two units are equal cannot observe a bug that swaps them - MUTATION.md habit 4,
+and the defect this repository has now shipped six cards in a row.
+
+⚠️ INVERTER B DOES NOT PHYSICALLY EXIST (~2026-09-12). Every number attributed
+to it below is SIMULATED, from the datasheet and serial recorded in NOTES.md
+§1.1b (GW5048D-ES, serial 55048ESU22AW0992, max_w 4600 W). Nothing here is
+measured, and nothing here should ever be quoted as if it were.
+
+⚠️ MUTATING THE MODULE THIS FILE GRADES? PURGE `__pycache__` FIRST - or run
+`tools/mutation_run.sh`, which does. `python3 -B` alone does NOT save you: it
+stops bytecode being WRITTEN, not a stale one being READ. Read MUTATION.md.
+Part 8 sidesteps the whole problem by exec'ing mutated SOURCE into a fresh
+namespace, so no `.pyc` is involved at any point.
+"""
+
+import ast
+import asyncio
+import hashlib
+import json
+import re
+import sys
+from pathlib import Path
+
+from app import mqtt
+from app.inverter import build_roster, roster_names
+from app.main import Controller
+
+HERE = Path(__file__).resolve().parent
+MQTT_SRC = (HERE / "app" / "mqtt.py").read_text(encoding="utf-8")
+
+fails = []
+
+
+def check(name, cond):
+    print(f"  {'ok  ' if cond else 'FAIL'} {name}")
+    if not cond:
+        fails.append(name)
+
+
+# ---------------------------------------------------------------------------
+# The recorded baseline. ⚠️ GENERATED, NOT TRANSCRIBED. Reproduce it with:
+#
+#   git show release/1.0:goodwe_controller/app/mqtt.py > /tmp/mqtt_base.py
+#   python3 - <<'EOF'
+#   import sys; sys.path.insert(0, "/tmp"); import mqtt_base as M
+#   class F:
+#       def __init__(self): self.m = []
+#       def publish(self, t, p=None, retain=False): self.m.append((t, p, retain))
+#   p = M.MqttPublisher.__new__(M.MqttPublisher)
+#   p.omit, p.client, p.enabled = set(), F(), True
+#   p._announce()
+#   for row in p.client.m: print(row)
+#   EOF
+#
+# A transcription would be a check that grades this branch against MY MEMORY of
+# release/1.0 rather than against release/1.0.
+# ---------------------------------------------------------------------------
+_DEV = ('{"identifiers": ["goodwe_rs485_controller"], "name": "GoodWe", '
+        '"manufacturer": "GoodWe (via RS485 meter emulation)", '
+        '"model": "ES/BP series"}')
+
+BASELINE = [
+    ('homeassistant/sensor/goodwe_ctl_setpoint/config',
+     '{"name": "Setpoint", "object_id": "goodwe_setpoint", "unique_id": "goodwe_ctl_setpoint", '
+     '"state_topic": "goodwe_ctl/setpoint", "availability_topic": "goodwe_ctl/availability", '
+     '"device": ' + _DEV + ', "unit_of_measurement": "W", "device_class": "power", '
+     '"state_class": "measurement"}', True),
+    ('homeassistant/sensor/goodwe_ctl_grid/config',
+     '{"name": "Grid power", "object_id": "goodwe_grid_power", "unique_id": "goodwe_ctl_grid", '
+     '"state_topic": "goodwe_ctl/grid", "availability_topic": "goodwe_ctl/availability", '
+     '"device": ' + _DEV + ', "unit_of_measurement": "W", "device_class": "power", '
+     '"state_class": "measurement"}', True),
+    ('homeassistant/sensor/goodwe_ctl_battery/config',
+     '{"name": "Battery power", "object_id": "goodwe_battery_power", "unique_id": "goodwe_ctl_battery", '
+     '"state_topic": "goodwe_ctl/battery", "availability_topic": "goodwe_ctl/availability", '
+     '"device": ' + _DEV + ', "unit_of_measurement": "W", "device_class": "power", '
+     '"state_class": "measurement"}', True),
+    ('homeassistant/sensor/goodwe_ctl_soc/config',
+     '{"name": "Battery SoC", "object_id": "goodwe_battery_soc", "unique_id": "goodwe_ctl_soc", '
+     '"state_topic": "goodwe_ctl/soc", "availability_topic": "goodwe_ctl/availability", '
+     '"device": ' + _DEV + ', "unit_of_measurement": "%", "device_class": "battery", '
+     '"state_class": "measurement"}', True),
+    ('homeassistant/sensor/goodwe_ctl_circulation/config',
+     '{"name": "Circulating power", "object_id": "goodwe_circulating_power", '
+     '"unique_id": "goodwe_ctl_circulation", "state_topic": "goodwe_ctl/circulation", '
+     '"availability_topic": "goodwe_ctl/availability", "device": ' + _DEV + ', '
+     '"unit_of_measurement": "W", "device_class": "power", "state_class": "measurement", '
+     '"icon": "mdi:sync-alert"}', True),
+    ('homeassistant/sensor/goodwe_ctl_phase/config',
+     '{"name": "Maintenance phase", "object_id": "goodwe_maintenance_phase", '
+     '"unique_id": "goodwe_ctl_phase", "state_topic": "goodwe_ctl/phase", '
+     '"availability_topic": "goodwe_ctl/availability", "device": ' + _DEV + ', '
+     '"icon": "mdi:battery-sync"}', True),
+    ('homeassistant/sensor/goodwe_ctl_status/config',
+     '{"name": "Controller status", "object_id": "goodwe_controller_status", '
+     '"unique_id": "goodwe_ctl_status", "state_topic": "goodwe_ctl/status", '
+     '"availability_topic": "goodwe_ctl/availability", "device": ' + _DEV + ', '
+     '"icon": "mdi:heart-pulse"}', True),
+    ('homeassistant/sensor/goodwe_ctl_p1_age/config',
+     '{"name": "P1 sample age", "object_id": "p1_sample_age_s", "unique_id": "goodwe_ctl_p1_age", '
+     '"state_topic": "goodwe_ctl/p1_age", "availability_topic": "goodwe_ctl/availability", '
+     '"device": ' + _DEV + ', "unit_of_measurement": "s", "device_class": "duration", '
+     '"state_class": "measurement"}', True),
+    ('goodwe_ctl/availability', 'online', True),
+]
+
+
+class FakeClient:
+    """Captures what `_announce()` actually hands paho."""
+
+    def __init__(self):
+        self.msgs = []
+
+    def publish(self, topic, payload=None, retain=False):
+        self.msgs.append((topic, payload, retain))
+
+
+def announce(units=(), omit=(), module=mqtt):
+    """The messages `_announce()` publishes, through the SHIPPED method.
+
+    ⚠️ Not `discovery_payloads()` directly. Part 2 proves the two agree; every
+    other part goes through this one, so what is diffed is what paho is told.
+    """
+    pub = module.MqttPublisher.__new__(module.MqttPublisher)
+    pub.omit = set(omit)
+    pub.units = [str(u) for u in units]
+    pub.enabled = True
+    pub.client = FakeClient()
+    pub._announce()
+    return pub.client.msgs
+
+
+def diff(got, want=BASELINE):
+    """`(missing, changed, added)` between two announcement lists, by topic."""
+    g, w = dict((t, (p, r)) for t, p, r in got), dict((t, (p, r)) for t, p, r in want)
+    missing = [t for t in w if t not in g]
+    changed = [t for t in w if t in g and g[t] != w[t]]
+    added = [t for t in g if t not in w]
+    return sorted(missing), sorted(changed), sorted(added)
+
+
+def report(label, got, want=BASELINE):
+    m, c, a = diff(got, want)
+    print(f"    {label}: {len(want)} topics, {len(m)} missing, {len(c)} changed, "
+          f"{len(a)} added")
+    for t in m:
+        print(f"      MISSING {t}")
+    for t in c:
+        print(f"      CHANGED {t}")
+    for t in a:
+        print(f"      ADDED   {t}")
+    return m, c, a
+
+
+def cfgs(msgs):
+    """The discovery payloads, parsed, without the availability message."""
+    return [json.loads(p) for t, p, _ in msgs if t.startswith("homeassistant/")]
+
+
+# The roster this card exists for. ⚠️ SIMULATED: inverter B does not physically
+# exist. Its rating is the datasheet's (NOTES.md §1.1b, GW5048D-ES, serial
+# 55048ESU22AW0992) and has never been measured.
+OPTS2 = {
+    "meter_source": "off",
+    "inverters": [
+        {"name": "inverter-a", "setpoint_entity": "number.sp_a",
+         "soc_entity": "sensor.soc_a", "batt_entity": "sensor.batt_a",
+         "max_w": 2000, "bms_soc_floor": 10},
+        {"name": "inverter-b", "setpoint_entity": "number.sp_b",
+         "soc_entity": "sensor.soc_b", "batt_entity": "sensor.batt_b",
+         "max_w": 4600, "bms_soc_floor": 10},
+    ],
+}
+NAMES2 = roster_names(OPTS2)
+
+
+# ---------------------------------------------------------------------------
+print("\n1. the recorded baseline, and a roster of one")
+# ---------------------------------------------------------------------------
+# AC 1 and AC 4. ⚠️ THE COMPARISON IS BYTE-FOR-BYTE ON THE PAYLOAD STRING, not
+# on a parsed dict. `json.dumps` writes keys in insertion order, so a reordered
+# payload is a different retained message on the broker even though the parsed
+# dicts compare equal - and a reordered payload is a re-announcement of every
+# entity on a live install.
+m, c, a = report("roster of one (`inverters:` empty, i.e. every install today)",
+                 announce(units=roster_names({})))
+check("⭐ AT THE SHIPPED ROSTER OF ONE THE ANNOUNCEMENT IS BYTE-IDENTICAL TO "
+      "release/1.0: same topics, same unique_ids, same payload bytes, same "
+      "retain flags, in the same order - no second device, no renamed entity, "
+      "no added topic",
+      (m, c, a) == ([], [], []) and announce(units=roster_names({})) == BASELINE)
+
+check("...and the roster-of-one path is the one every install actually reads: "
+      "an empty `inverters:` names exactly one unit",
+      roster_names({}) == ["inverter-a"])
+
+check("...and a publisher told NOTHING about the roster announces the same "
+      "thing, so a caller that has not been taught about units cannot change "
+      "what a live install sees",
+      announce(units=()) == BASELINE)
+
+m, c, a = report("roster of one, P1 off (`omit=('p1_age',)`)",
+                 announce(units=roster_names({}), omit=("p1_age",)),
+                 [row for row in BASELINE if "p1_age" not in row[0]])
+check("...and the `omit` path is unchanged too: with P1 ingestion off the "
+      "watchdog input is still not announced, and nothing else moved",
+      (m, c, a) == ([], [], []))
+
+# ---------------------------------------------------------------------------
+print("\n2. what is diffed is what goes on the wire")
+# ---------------------------------------------------------------------------
+# ⚠️ WITHOUT THIS PART, PARTS 1 AND 3-8 GRADE A FUNCTION THE ADD-ON MIGHT NOT
+# USE. `_announce()` used to build its payloads inline; if it still did, every
+# diff here would be a diff of a second implementation that happens to sit in
+# the same file. This is the join.
+_direct = [(t, json.dumps(cfg), True)
+           for t, cfg in mqtt.discovery_payloads(NAMES2)] + \
+          [(mqtt.AVAILABILITY, "online", True)]
+check("`_announce()` publishes EXACTLY `discovery_payloads()`, in order, with "
+      "retain set, plus the availability message - so every diff in this file "
+      "is a diff of the bytes paho is handed",
+      announce(units=NAMES2) == _direct)
+
+# ---------------------------------------------------------------------------
+print("\n3. a roster of two: A untouched, B added")
+# ---------------------------------------------------------------------------
+TWO = announce(units=NAMES2)
+m, c, a = report("roster of two (inverter-a + inverter-b, SIMULATED)", TWO)
+check("⭐ AC 1: AT A ROSTER OF TWO, EVERY ONE OF A's NINE MESSAGES IS STILL "
+      "BYTE-IDENTICAL - nothing missing, nothing changed. This is the criterion "
+      "the live install's recorded history depends on, and it is a diff of the "
+      "payloads, not a reading of the code",
+      (m, c) == ([], []))
+check("...and the eight additions are all B's and A's own per-unit rows, and "
+      "all of them are NEW topics", len(a) == 8)
+check("...and A's nine messages are still the FIRST nine, in the same order, "
+      "so a broker replaying retained messages sees them unchanged",
+      TWO[:len(BASELINE) - 1] == BASELINE[:-1])
+
+site_ids = {c_["unique_id"] for c_ in cfgs(BASELINE)}
+unit_cfgs = [c_ for c_ in cfgs(TWO) if c_["unique_id"] not in site_ids]
+a_cfgs = [c_ for c_ in unit_cfgs if "inverter_a" in c_["unique_id"]]
+b_cfgs = [c_ for c_ in unit_cfgs if "inverter_b" in c_["unique_id"]]
+check("A's per-unit rows stay on THE DEVICE A ALREADY HAS - no new device is "
+      "created for the first roster entry, which is the whole asymmetry",
+      len(a_cfgs) == 4
+      and all(c_["device"] == mqtt.DEVICE for c_ in a_cfgs))
+check("⭐ AC 2: B's rows are on B's OWN device, with its own identifiers",
+      len(b_cfgs) == 4
+      and all(c_["device"]["identifiers"] == ["goodwe_rs485_controller_inverter_b"]
+              for c_ in b_cfgs))
+check("...and B's device hangs off the controller's via `via_device`, so HA "
+      "shows one controller driving two inverters rather than two strangers",
+      all(c_["device"].get("via_device") == mqtt.DEVICE["identifiers"][0]
+          for c_ in b_cfgs))
+check("...and B's device carries the SAME manufacturer and model as the site "
+      "device - it is the same installation, not a second product",
+      all(c_["device"]["manufacturer"] == mqtt.DEVICE["manufacturer"]
+          and c_["device"]["model"] == mqtt.DEVICE["model"] for c_ in b_cfgs))
+
+# A regression pin on the NEW payloads. ⚠️ THIS IS NOT EVIDENCE OF CORRECTNESS -
+# it is generated from this branch, so it can only say "these bytes have not
+# changed since the PR was reviewed". It exists because B's payloads have no
+# released version to be diffed against, and a later edit that quietly changes
+# a per-unit `device_class` or state topic should have to be deliberate.
+_pin = hashlib.sha256(
+    json.dumps(unit_cfgs, sort_keys=False).encode()).hexdigest()[:16]
+print("    the eight per-unit payloads, in announcement order:")
+for c_ in unit_cfgs:
+    print(f"      {c_['unique_id']:<40} {c_['object_id']:<34} "
+          f"{c_['state_topic']}")
+print(f"    regression pin (sha256 of the eight payloads): {_pin}")
+check("the per-unit payloads are the ones this PR was reviewed with "
+      "(REGRESSION PIN, not a correctness claim - see the comment)",
+      _pin == "eb5022b0455158d7")
+
+# ---------------------------------------------------------------------------
+print("\n4. zero overlap between A's entities and B's")
+# ---------------------------------------------------------------------------
+def field(rows, key):
+    return [r[key] for r in rows]
+
+
+for key in ("unique_id", "object_id", "state_topic"):
+    av, bv = set(field(a_cfgs, key)), set(field(b_cfgs, key))
+    sv = set(field(cfgs(BASELINE), key))
+    check(f"⭐ AC 2: no `{key}` is shared between A's entities and B's, and "
+          f"none of B's collides with a SITE entity that already exists",
+          len(av) == 4 and len(bv) == 4 and not (av & bv) and not (bv & sv)
+          and not (av & sv))
+
+all_ids = field(cfgs(TWO), "unique_id")
+check("...and across the WHOLE announcement every unique_id is distinct - an "
+      "HA discovery collision is not an error, it DROPS the second entity, so "
+      "one inverter's telemetry would silently stop existing",
+      len(all_ids) == len(set(all_ids)) == 16)
+
+all_topics = [t for t, _, _ in TWO]
+check("...and so is every topic", len(all_topics) == len(set(all_topics)) == 17)
+
+# ⚠️ THE SLUG COLLISION rule 9(c) DOES NOT REFUSE. `inverter-b` and `Inverter B`
+# are two different names by the validator's test and one string once slugged.
+COLLIDE = announce(units=["inverter-b", "Inverter B"])
+col_ids = field(cfgs(COLLIDE), "unique_id")
+print("    two names that slug alike ('inverter-b', 'Inverter B') ->",
+      [c_["unique_id"] for c_ in cfgs(COLLIDE) if c_["unique_id"] not in site_ids])
+check("two roster names that differ only in case and punctuation - which "
+      "`validate.py` rule 9(c) accepts, because it refuses only EXACT "
+      "duplicates - still get distinct unique_ids",
+      len(col_ids) == len(set(col_ids)))
+
+# ---------------------------------------------------------------------------
+print("\n5. site-scoped sensors stay site-scoped")
+# ---------------------------------------------------------------------------
+# ⚠️ `p1_sample_age_s` IS A WATCHDOG INPUT (mqtt.py's `omit` note and the ESP32
+# firmware's ingest guard). A second copy of it is a second answer to "is the
+# meter fresh?", one of which is always the one nobody is looking at. `grid` is
+# the same argument without the safety edge: there is ONE grid connection.
+SITE_ONLY = ("goodwe_ctl_grid", "goodwe_ctl_p1_age", "goodwe_ctl_circulation",
+             "goodwe_ctl_phase", "goodwe_ctl_status")
+rows = []
+for n in range(1, 7):
+    names = [f"inverter-{chr(ord('a') + i)}" for i in range(n)]
+    ids = field(cfgs(announce(units=names)), "unique_id")
+    rows.append((n, [ids.count(s) for s in SITE_ONLY], len(ids)))
+    print(f"    roster of {n}: {len(ids)} entities, "
+          + ", ".join(f"{s}x{ids.count(s)}" for s in SITE_ONLY))
+check("⭐ AC 3: `grid` and `p1_sample_age_s` are announced EXACTLY ONCE at every "
+      "roster length from 1 to 6 - announcing them per inverter would invent "
+      "two of a thing there is one of, and would duplicate a safety signal",
+      all(counts == [1] * len(SITE_ONLY) for _n, counts, _t in rows))
+check("...and the site set does not grow with the roster while the per-unit "
+      "set does: 8 site entities always, 4 more per unit past the first",
+      [t for _n, _c, t in rows] == [8, 16, 20, 24, 28, 32])
+
+site_devices = {json.dumps(c_["device"], sort_keys=True)
+                for c_ in cfgs(announce(units=NAMES2))
+                if c_["unique_id"] in site_ids}
+check("...and every site entity is still on the SITE device, at a roster of two",
+      site_devices == {json.dumps(mqtt.DEVICE, sort_keys=True)})
+
+# ---------------------------------------------------------------------------
+print("\n6. the composed entity_ids")
+# ---------------------------------------------------------------------------
+# ⚠️ THIS SLUGIFIER IS DELIBERATELY NOT `mqtt._slug`. Importing the module's own
+# spelling would make the model and the subject move together, so a mutation in
+# the slugifier would change both sides equally and be invisible - "a check
+# whose data cannot reach the failure it names", written in one import.
+def compose(device_name, entity_name):
+    """HA's entity_id for a discovery payload, per mqtt.py's own note."""
+    s = re.sub(r"[^a-z0-9]+", "_", f"{device_name} {entity_name}".lower())
+    return "sensor." + s.strip("_")
+
+
+# The ONE anchor there is: mqtt.py records that the live entity is
+# `sensor.goodwe_p1_sample_age`, verified against the live system 2026-08-26,
+# and that the firmware subscribes to that composed name. If this model does not
+# reproduce that id, the model is wrong and every claim below it is worthless.
+p1 = [c_ for c_ in cfgs(BASELINE) if c_["unique_id"] == "goodwe_ctl_p1_age"][0]
+check("the model reproduces the ONE composed entity_id that was verified "
+      "against the live system - `sensor.goodwe_p1_sample_age`, which the ESP32 "
+      "ingest guard subscribes to - from the device name and the entity name",
+      compose(mqtt.DEVICE["name"], p1["name"]) == "sensor.goodwe_p1_sample_age")
+check("...and that id is NOT the `object_id` in the payload "
+      "(`p1_sample_age_s`), which is the whole reason the device name is "
+      "load-bearing and mqtt.py says so in capitals",
+      p1["object_id"] != "goodwe_p1_sample_age")
+
+composed = [compose(c_["device"]["name"], c_["name"]) for c_ in cfgs(TWO)]
+print("    every composed entity_id at a roster of two:")
+for c_, eid in zip(cfgs(TWO), composed):
+    print(f"      {eid:<46} <- device {c_['device']['name']!r} + "
+          f"name {c_['name']!r}")
+check("⭐ every composed entity_id at a roster of two is DISTINCT: no per-unit "
+      "entity can land on top of a site entity that already has history",
+      len(composed) == len(set(composed)) == 16)
+
+base_composed = [compose(c_["device"]["name"], c_["name"]) for c_ in cfgs(BASELINE)]
+check("...and the eight ids that exist today are unchanged by adding B, which "
+      "is AC 1 restated in the units HA actually uses",
+      composed[:8] == base_composed)
+
+check("...and the per-unit ids come out SYMMETRIC even though the devices are "
+      "not - sensor.goodwe_inverter_a_battery_power beside "
+      "sensor.goodwe_inverter_b_battery_power - which is the entire benefit of "
+      "the 'one device per inverter' design, without its cost",
+      "sensor.goodwe_inverter_a_battery_power" in composed
+      and "sensor.goodwe_inverter_b_battery_power" in composed)
+
+check("...and for every per-unit entity `object_id` equals the composed id, so "
+      "the two mechanisms agree and an HA that DID honour object_id would "
+      "produce the same ids as one that does not",
+      all("sensor." + c_["object_id"] == compose(c_["device"]["name"], c_["name"])
+          for c_ in unit_cfgs))
+
+# ---------------------------------------------------------------------------
+print("\n7. the announcement and the publication agree")
+# ---------------------------------------------------------------------------
+# ⚠️ THE HAZARD mqtt.py's `omit` NOTE NAMES: an entity that exists and is never
+# fed is a worse signal than one that does not exist. So the set of per-unit
+# topics ANNOUNCED and the set `Controller.publish()` actually writes have to be
+# the same set - and, because a matching set of KEYS is not a matching set of
+# VALUES, the two units carry DIFFERENT numbers here so that a swap is red.
+class _Store:
+    data = {}
+
+    def set(self, *a):
+        pass
+
+    def get_time(self, *a):
+        return None
+
+
+class _Pub:
+    def __init__(self):
+        self.last = {}
+        self.units = []
+
+    def publish(self, values):
+        self.last = dict(values)
+
+    def close(self):
+        pass
+
+
+def controlled(opts, soc, batt, tripped):
+    """A real Controller with per-unit readings planted. SIMULATED values."""
+    # ⚠️ `stop` is a REQUIRED keyword (CFG-01): a Controller that cannot stop
+    # itself used to be the default one. These cases only call publish(), so any
+    # Event will do - but they may not skip it.
+    pub = _Pub()
+    ctl = Controller(dict(opts), None, _Store(), pub, stop=asyncio.Event())
+    for inv, s, b, t in zip(ctl.inverters, soc, batt, tripped):
+        inv.soc, inv.batt, inv.target = s, b, -1.0 * b
+        inv.sign_wd.tripped = t
+    ctl.publish()
+    return ctl, pub.last
+
+
+# A 41 / 88 %, A discharging 1200 W, B charging 300 W, and B latched, not A.
+# Every one of those six numbers differs from its sibling, which is what makes
+# the assertions below able to see a swap.
+ctl2, vals2 = controlled(OPTS2, [41.0, 88.0], [1200.0, -300.0], [False, True])
+announced_unit_topics = {c_["state_topic"] for c_ in unit_cfgs}
+published_unit_topics = {f"{mqtt.BASE}/{k}" for k in vals2 if k.startswith("unit/")}
+print(f"    announced per-unit topics {len(announced_unit_topics)}, "
+      f"published {len(published_unit_topics)}, "
+      f"announced-but-never-fed {sorted(announced_unit_topics - published_unit_topics)}, "
+      f"fed-but-never-announced {sorted(published_unit_topics - announced_unit_topics)}")
+check("⭐ every per-unit entity announced is one the controller actually "
+      "publishes to, and every per-unit topic published is one that was "
+      "announced - no entity that nothing feeds, no topic nothing declared",
+      announced_unit_topics == published_unit_topics)
+
+check("⭐ AND THE VALUES LAND ON THE RIGHT UNIT: A's 41 % on A's topic and B's "
+      "88 % on B's, not the other way round",
+      vals2["unit/inverter_a/soc"] == 41.0
+      and vals2["unit/inverter_b/soc"] == 88.0)
+check("...and the same for battery power, whose SIGNS differ between the two "
+      "units here (A discharging, B charging) so a swap cannot hide in a "
+      "magnitude",
+      vals2["unit/inverter_a/battery"] == 1200.0
+      and vals2["unit/inverter_b/battery"] == -300.0)
+check("...and the SAFETY-02 sign latch is per unit: B is latched and A is not, "
+      "and the two rows say so separately",
+      vals2["unit/inverter_a/sign_latch"] == "clear"
+      and vals2["unit/inverter_b/sign_latch"] == "tripped")
+check("...and each unit's setpoint row is its OWN share, not the site target",
+      vals2["unit/inverter_a/setpoint"] == -1200.0
+      and vals2["unit/inverter_b/setpoint"] == 300.0)
+
+check("...and the SITE rows still mean what they meant: `soc` is the EMPTIEST "
+      "pack (41 %, not 88 and not the mean) and `battery` is the SUM (900 W), "
+      "so this card added rows beside them and did not re-point them",
+      vals2["soc"] == 41.0 and round(vals2["battery"]) == 900)
+
+_, vals1 = controlled({"meter_source": "off", "setpoint_entity": "number.sp"},
+                      [55.0], [700.0], [False])
+print(f"    roster of one publishes keys: {sorted(vals1)}")
+check("⭐ AC 4 on the PUBLISH side: at a roster of one not one `unit/...` topic "
+      "is written either, so the live install's broker sees no new topic at all",
+      not [k for k in vals1 if k.startswith("unit/")])
+
+# --- 7b. the wiring, which nothing above reaches -----------------------------
+# ⚠️ FOUND BY MUTATION, NOT BY DESIGN. `units=()` in main()'s `MqttPublisher(...)`
+# call survived every check in this file: parts 1-7 build the publisher
+# themselves, so a controller publishing eight per-unit topics beside a
+# publisher announcing none of them was GREEN. That is this repository's
+# recurring defect - a check whose data cannot reach the failure it names - in
+# the one line that joins the two halves together.
+check("`roster_names()` and `build_roster()` give the same names in the same "
+      "order, on every shape - the flat keys, a declared roster, a nameless "
+      "entry and a non-dict entry - so the names the publisher is handed are "
+      "the names the units answer to",
+      all([inv.name for inv in build_roster(o, None)] == roster_names(o)
+          for o in ({}, {"setpoint_entity": "number.sp"}, OPTS2,
+                    {"inverters": [{}, {}]},
+                    {"inverters": [{"name": "roof west"}, "junk"]})))
+check("...and a nameless entry gets a POSITIONAL name, not `inverter-a` twice: "
+      "two units under one name share one Store namespace, so one unit's "
+      "SAFETY-02 latch would be the other's",
+      roster_names({"inverters": [{}, {}]}) == ["inverter-1", "inverter-2"])
+
+_call = [n for n in ast.walk(ast.parse((HERE / "app" / "main.py").read_text()))
+         if isinstance(n, ast.Call) and isinstance(n.func, ast.Name)
+         and n.func.id == "MqttPublisher"]
+_kw = [k for c_ in _call for k in c_.keywords if k.arg == "units"]
+print(f"    main.py builds MqttPublisher {len(_call)} time(s); "
+      f"units= is " + (ast.unparse(_kw[0].value) if _kw else "ABSENT"))
+check("⚠️ A SOURCE READ, AND THE WEAKEST CHECK IN THIS FILE - said so rather "
+      "than dressed up. main()'s one `MqttPublisher(...)` hands it "
+      "`roster_names(opts)`; nothing else here can reach that line, because "
+      "main() opens a broker, a web server and a control loop",
+      len(_call) == 1 and len(_kw) == 1
+      and ast.unparse(_kw[0].value) == "roster_names(opts)")
+
+# --- 7c. a name that is not ASCII -------------------------------------------
+# HA transliterates before it slugs; this module cannot, so it treats anything
+# outside ASCII as a separator. Either way the id must be an id.
+_odd = announce(units=["caf\u00e9-a", "caf\u00e9-b"])
+_odd_unit = [c_ for c_ in cfgs(_odd) if c_["unique_id"] not in site_ids]
+print("    a roster named with non-ASCII ->",
+      sorted({c_["unique_id"] for c_ in _odd_unit}))
+check("every unique_id, object_id and state topic this module produces is "
+      "lowercase ASCII, even from a roster name that is not - an id HA would "
+      "not have composed is an entity nothing can subscribe to",
+      _odd_unit
+      and all(re.fullmatch(r"[a-z0-9_]+", c_[k])
+              for c_ in _odd_unit for k in ("unique_id", "object_id"))
+      and all(re.fullmatch(r"[a-z0-9_/]+", c_["state_topic"])
+              for c_ in _odd_unit))
+
+# The topics the SHIPPED controller actually feeds at a roster of two. Part 8
+# grades every mutant announcement against this, which is what turns "the
+# announcement changed" into "the announcement now claims an entity nothing
+# will ever publish to".
+FED = set(published_unit_topics)
+
+# ---------------------------------------------------------------------------
+print("\n8. verified by breaking it")
+# ---------------------------------------------------------------------------
+# ⚠️ MUTATED SOURCE, EXEC'D INTO A FRESH NAMESPACE. No file is edited and no
+# `.pyc` is consulted, so TEST-15's stale-bytecode failure cannot produce a
+# false survivor here. `app/mqtt.py` imports nothing from this package, which is
+# what makes exec'ing it standalone honest rather than a stub.
+def load(pairs):
+    """`app/mqtt.py` with `pairs` applied, executed into a fresh module.
+
+    ⚠️ EVERY ANCHOR MUST OCCUR EXACTLY ONCE. A mutation whose anchor has drifted
+    out of the file would otherwise apply to nothing and be reported as a
+    survivor - a false red on the instrument rather than on the module.
+    """
+    src = MQTT_SRC
+    for old, new in pairs:
+        if src.count(old) != 1:
+            raise AssertionError(f"mutation anchor not unique: {old!r}")
+        src = src.replace(old, new)
+    mod = type(sys)("mqtt_mutant")
+    exec(compile(src, "<mutant>", "exec"), mod.__dict__)
+    return mod
+
+
+def properties(mod):
+    """Every claim this file makes, as booleans, over ONE module."""
+    out = {}
+    try:
+        base = announce(units=["inverter-a"], module=mod)
+        two = announce(units=["inverter-a", "inverter-b"], module=mod)
+        none = announce(units=(), module=mod)
+        col = announce(units=["inverter-b", "Inverter B"], module=mod)
+        tc = cfgs(two)
+        uc = [c_ for c_ in tc if c_["unique_id"] not in site_ids]
+        bc = [c_ for c_ in uc if "inverter_b" in c_["unique_id"]]
+        ac = [c_ for c_ in uc if "inverter_a" in c_["unique_id"]]
+        comp = [compose(c_["device"]["name"], c_["name"]) for c_ in tc]
+        out["A byte-identical at N=1"] = base == BASELINE
+        out["A byte-identical at N=2"] = diff(two)[:2] == ([], [])
+        out["N=1 adds no topic"] = len(base) == len(none) == len(BASELINE)
+        out["unique_ids all distinct"] = (
+            len(set(c_["unique_id"] for c_ in tc)) == len(tc))
+        out["slug-alike names still distinct"] = (
+            len(set(c_["unique_id"] for c_ in cfgs(col))) == len(cfgs(col)))
+        out["no composed entity_id collision"] = len(set(comp)) == len(comp)
+        out["object_id == composed id"] = all(
+            "sensor." + c_["object_id"] == compose(c_["device"]["name"], c_["name"])
+            for c_ in uc)
+        out["A keeps the device it has"] = bool(ac) and all(
+            c_["device"] == mqtt.DEVICE for c_ in ac)
+        out["B has its own device"] = bool(bc) and all(
+            c_["device"]["identifiers"] != mqtt.DEVICE["identifiers"] for c_ in bc)
+        out["B is via_device the site"] = bool(bc) and all(
+            c_["device"].get("via_device") == mqtt.DEVICE["identifiers"][0]
+            for c_ in bc)
+        out["site sensors announced once"] = all(
+            [c_["unique_id"] for c_ in cfgs(announce(units=[f"i{j}" for j in range(n)],
+                                                     module=mod))].count(s) == 1
+            for n in (1, 2, 3) for s in SITE_ONLY)
+        # ⚠️ TWO PROPERTIES THAT WERE MISSING, AND THE INSTRUMENT FOUND THEIR
+        # ABSENCE ITSELF: on the first run of this table, "the unit is dropped
+        # from the state topic" and "`grid` is moved to the per-unit set" were
+        # both GREEN. The first collapses A's and B's four topics onto one set
+        # of four, so both inverters read one number; the second announces a
+        # per-inverter grid sensor, which is the exact thing AC 3 forbids. The
+        # ids stayed distinct through both, so every property above missed them.
+        out["per-unit state topics all distinct"] = (
+            len({c_["state_topic"] for c_ in uc}) == len(uc))
+        # ⚠️ GRADED AGAINST THE SHIPPED `Controller.publish()`, on purpose. An
+        # announcement is only honest if something feeds it - mqtt.py's `omit`
+        # note - so a per-unit entity the controller will never publish to is a
+        # defect however tidy its id looks. (A rename applied to BOTH halves at
+        # once is invisible here and is disclosed in part 9; a rename applied to
+        # one half is what actually happens, and is red.)
+        out["every announced per-unit topic is fed"] = (
+            {c_["state_topic"] for c_ in uc} == FED)
+    except Exception as err:  # a mutation that CRASHES proves nothing; say so
+        out["did not raise"] = False
+        out["__error__"] = repr(err)[:70]
+    return out
+
+
+SHIPPED = properties(mqtt)
+check("the shipped module satisfies every property this instrument grades - "
+      "so a red below is the mutation and not the instrument",
+      all(v is True for k, v in SHIPPED.items()))
+
+MUTATIONS = [
+    ("⭐ RE-SCOPE A's DEVICE NAME (the destructive change, AC 5)",
+     [('"name": "GoodWe",', '"name": "GoodWe Inverter A",')]),
+    ("⭐ RE-SCOPE A's DEVICE IDENTIFIERS",
+     [('"identifiers": ["goodwe_rs485_controller"],',
+       '"identifiers": ["goodwe_inverter_a"],')]),
+    ("⭐ THE TEMPTING TIDY DESIGN: one device per inverter, A included",
+     [("device = DEVICE if i == 0 else unit_device(name, slug)",
+       "device = unit_device(name, slug)"),
+      ('prefix = f"{_title(name)} " if i == 0 else ""', 'prefix = ""')]),
+    ("B's rows land on A's device instead of B's own",
+     [("device = DEVICE if i == 0 else unit_device(name, slug)",
+       "device = DEVICE")]),
+    ("A's per-unit entity names lose the unit prefix",
+     [('prefix = f"{_title(name)} " if i == 0 else ""', 'prefix = ""')]),
+    ("per-unit entities announced at a roster of ONE",
+     [("PER_UNIT_MIN_ROSTER = 2", "PER_UNIT_MIN_ROSTER = 1")]),
+    ("the unit is dropped from the unique_id",
+     [('unique_id = f"{BASE}_unit_{slug}_{key}"',
+       'unique_id = f"{BASE}_unit_{key}"')]),
+    ("the unit is dropped from the state topic",
+     [('return f"unit/{slug}/{key}"', 'return f"unit/{key}"')]),
+    ("the slug de-collision is removed (rule 9(c) does not cover this)",
+     [("while slug in seen:", "while False and slug in seen:")]),
+    ("every unit takes the FIRST unit's slug",
+     [("for i, (name, slug) in enumerate(zip(names, slugs)):",
+       "for i, (name, slug) in enumerate(zip(names, [slugs[0]] * len(slugs))):")]),
+    ("`grid` is moved to the per-unit set (site sensor announced per inverter)",
+     [('    ("setpoint", "setpoint", "Setpoint", "W", "power", "measurement", None),\n',
+       '    ("setpoint", "setpoint", "Setpoint", "W", "power", "measurement", None),\n'
+       '    ("grid", "grid_power", "Grid power", "W", "power", "measurement", None),\n')]),
+    ("B's device drops `via_device`",
+     [('        "via_device": DEVICE["identifiers"][0],\n', "")]),
+]
+
+survivors = []
+for label, pairs in MUTATIONS:
+    got = properties(load(pairs))
+    broke = sorted(k for k, v in SHIPPED.items()
+                   if v is True and got.get(k) is not True)
+    if not broke:
+        survivors.append(label)
+    print(f"    {'RED ' if broke else 'GREEN'} {label}")
+    if broke:
+        print(f"           breaks: {', '.join(broke)}")
+    elif got.get("__error__"):
+        print(f"           raised: {got['__error__']}")
+check(f"⭐ ALL {len(MUTATIONS)} MUTATIONS ARE RED, each on a NAMED property: "
+      "re-scoping A's device, the tidy one-device-per-inverter design, B "
+      "landing on A's device, per-unit entities at a roster of one, a unit "
+      "dropped from an id or a topic, two units sharing a slug, and a site "
+      "sensor announced per inverter. A mutation nothing catches is a claim "
+      "nothing is watching",
+      not survivors)
+if survivors:
+    print("       SURVIVED:", "; ".join(survivors))
+
+# ⚠️ AC 6, THE FIXTURE'S OWN NON-VACUITY. If A and B were given the same name
+# the whole of part 4 would still be green and would be observing nothing.
+same = announce(units=["inverter-a", "inverter-a"])
+swapped = announce(units=["inverter-b", "inverter-a"])
+check("...and the fixture's two units are genuinely distinguishable: swapping "
+      "their order changes the announcement, and a roster of two IDENTICAL "
+      "names - which rule 9(c) refuses, and which this file therefore never "
+      "relies on - would still not collide",
+      swapped != TWO
+      and len({c_["unique_id"] for c_ in cfgs(same)}) == len(cfgs(same)))
+
+# ---------------------------------------------------------------------------
+print("\n9. what this file CANNOT see, enumerated and sized")
+# ---------------------------------------------------------------------------
+for line in [
+    "1. HA ITSELF IS NOT IN THE LOOP. `compose()` in part 6 is a MODEL of how "
+    "HA 2026.8 builds an entity_id, anchored on exactly ONE measured id "
+    "(sensor.goodwe_p1_sample_age, mqtt.py's note, verified 2026-08-26). If HA "
+    "changes that rule, or if it differs for a device with `via_device`, every "
+    "id claim here moves with it and this file stays green. SIZE: the 8 "
+    "per-unit ids at N=2. It cannot be closed from this repository - it needs a "
+    "broker, an HA, and the owner present.",
+    "2. THE TICKET AND THE MODULE DISAGREE ABOUT THE LIVE IDs. The card quotes "
+    "`sensor.goodwe_rs485_controller_goodwe_battery_soc`; mqtt.py records "
+    "`sensor.goodwe_p1_sample_age`. Those cannot both come from one composition "
+    "rule - the first is the id an EARLIER device name composed, and HA keeps "
+    "whatever it composed at first discovery. This card does not need to "
+    "resolve it, because it renames no device and no entity, and the byte-diff "
+    "protects both spellings equally. SIZE: unresolved, 8 live entity ids; it "
+    "wants one look at the live registry, which this branch must not take.",
+    "3. THE PER-UNIT PAYLOADS HAVE NO RELEASED BASELINE. A's are diffed against "
+    "release/1.0; B's can only be diffed against this branch (the sha256 pin in "
+    "part 3). A wrong `device_class` or unit on a per-unit sensor is therefore "
+    "caught as a CHANGE from review, not as an error. SIZE: 4 sensors x 4 "
+    "optional fields.",
+    "4. NO CHECK HERE RUNS A BROKER. `_announce()` is graded through a fake "
+    "paho client, so QoS, retain semantics on a real broker, and what HA does "
+    "with a retained config for a device it has never seen are all out of "
+    "scope. SIZE: the whole transport.",
+    "5. THE SLUG DE-COLLISION IS ORDER-DEPENDENT. `inverter-b` before "
+    "`Inverter B` gives the SECOND one the `_2` suffix; reordering the roster "
+    "swaps which unit's ids move. Rule 9(c) does not refuse slug-alike names, "
+    "so this is reachable from a config an operator can write. SIZE: 4 ids on "
+    "one unit, and only when two names slug alike. Filed as a follow-up rather "
+    "than fixed in validate.py here, because a new refusal at startup on a "
+    "LIVE install is a bigger change than this card is allowed to be.",
+    "7. PART 8 MUTATES `app/mqtt.py` ONLY. `Controller.publish()`'s four "
+    "per-unit lines are graded by part 7 - with different SoC, different "
+    "battery sign and different latch states on the two units, so a swap or a "
+    "mis-paired slug is red - but no automated table mutates main.py here. "
+    "Those mutations were run by hand through `tools/mutation_run.sh` and are "
+    "recorded in the PR. SIZE: 4 lines. Also invisible: a rename of "
+    "`unit_state_key()` applied to BOTH halves at once, which is harmless "
+    "(the topics are internal) but would move every per-unit state topic "
+    "silently.",
+    "6. `inverter AC power` AND PER-UNIT HEARTBEAT AGE ARE NOT ANNOUNCED. The "
+    "card lists both as per-unit; neither has a source in the add-on today "
+    "(nothing reads an AC-power register per unit, and `inv.last_beat` is a "
+    "monotonic loop clock). Announcing them would create entities nothing "
+    "feeds. SIZE: 2 sensors x N units, deliberately absent, named in the PR.",
+]:
+    print("    " + line)
+
+# ---------------------------------------------------------------------------
+print()
+if fails:
+    print(f"{len(fails)} FAILED:")
+    for f in fails:
+        print("  -", f)
+    sys.exit(1)
+print("all checks passed")

goodwe_controller/test_translations.py

@@ -0,0 +1,369 @@
+"""UX-01 - the Configuration tab's labels, and the check that stops them rotting.
+
+RUN:  python3 -B test_translations.py       (no third-party imports; the add-on
+                                             CI image is Alpine + aiohttp + paho)
+
+WHAT THIS FILE IS FOR. Before UX-01 there was no `translations/` directory at
+all, so Home Assistant rendered the raw option KEYS - `unit_sign_disagree_w`,
+`saturation_cycles`, `integrator_max_w` - for all seventy options, in
+`schema:` order, with no description. The two files this grades are what turn
+that into sentences, and the highest-value half of them is not the label: it is
+the sentence that says WHETHER TO TOUCH THE VALUE, because the tab presents a
+constant derived from 1890 closed-loop test runs and the operator's own inverter
+rating as the same kind of field.
+
+⚠️ WHAT THIS FILE CANNOT SEE, SAID FIRST. It grades COVERAGE and PROVENANCE
+CITATIONS - that every option has a name and a description in both languages,
+that no translation names an option that does not exist, and that each derived
+constant's English description cites the record it was derived from. It does NOT
+grade whether a sentence is true, whether the Dutch is good Dutch, or whether
+the result looks right on screen. The last of those is measured, not asserted,
+by `tools/supervisor_shape_probe.py` section F, which loads these files with
+Supervisor 2026.08.0's OWN loader out of the release image, runs its OWN
+`UiOptions`, replays the frontend's label resolution as the shipped bundle
+writes it, and prints every rendered row. That transcript is the evidence; this
+file is the gate that keeps it true.
+
+⚠️ AND THE PARSER IS THE OTHER HALF OF THAT PAIR. There is no PyYAML in the CI
+image and a check that skips on ImportError is not a check, so
+`tools/translations_lint.py` parses these files by hand. A hand parser that
+quietly disagrees with the real loader is exactly the defect this repository
+keeps finding, so the probe imports THAT SAME MODULE and asserts, key by key and
+string by string, that it returns what `supervisor.store.data.
+_read_app_translations()` returns. Part 5 below re-states the arrangement so a
+reader of this file is told where the licence for the hand parser comes from.
+
+MUTATION.md is the method for the ledger in part 6; `tools/mutation_run.sh` is
+the harness, and every row there was RUN rather than reasoned about.
+"""
+
+import io
+import sys
+from pathlib import Path
+
+HERE = Path(__file__).resolve().parent
+sys.path.insert(0, str(HERE / "tools"))
+import translations_lint as TL                                    # noqa: E402
+
+FAILED = 0
+def check(what, ok):
+    global FAILED
+    print(("  ok   " if ok else "  FAIL ") + what)
+    if not ok:
+        FAILED += 1
+
+
+CFG_TEXT = io.open(HERE / "config.yaml", encoding="utf-8").read()
+ORDER, NESTED = TL.config_surface(CFG_TEXT)
+LANGS = ("en", "nl")
+TR = {lg: TL.parse_translation_file(HERE / "translations" / f"{lg}.yaml")
+      for lg in LANGS}
+
+print("UX-01 - add-on option translations\n")
+print("1. the surface being described")
+print(f"    config.yaml declares {len(ORDER)} top-level options under `schema:` "
+      f"and {sum(len(v) for v in NESTED.values())} per-entry key(s) under "
+      f"{sorted(NESTED)}")
+# ⚠️ A FLOOR, NOT AN EQUALITY. This is the "did the reader read anything at all"
+# line: `config_surface()` returning an empty list would make every coverage
+# check below vacuously true, which is the third failure mode in MUTATION.md -
+# the assertion runs, the sentence is true, and the data cannot reach the
+# failure it names.
+check(f"the option surface was actually read - {len(ORDER)} options, not zero",
+      len(ORDER) >= 60 and "inverters" in ORDER and "max_w" in ORDER)
+check("...and the repeatable `inverters:` section's per-entry keys were read "
+      "too, which is the half a top-level-only reader would miss",
+      NESTED.get("inverters", [])[:2] == ["name", "setpoint_entity"]
+      and len(NESTED["inverters"]) == 7)
+
+print("\n2. AC: every option and every per-entry key is translated, in BOTH "
+      "languages")
+for lg in LANGS:
+    problems = TL.audit(CFG_TEXT, TR[lg], lg)
+    print(f"    {lg}: {len(TR[lg]['configuration'])} options translated, "
+          f"{len(problems)} problem(s)")
+    for p in problems[:10]:
+        print("      - " + p)
+    check(f"`{lg}` covers config.yaml exactly: no option without a translation, "
+          f"no translation without an option, every one with a name AND a "
+          f"description. Problems: {problems[:3]}", not problems)
+
+# ⚠️ THE `nl` HALF IS NOT OPTIONAL EVEN THOUGH THE FALLBACK IS. The frontend
+# resolves `translations[lang]?.name || translations["en"]?.name || key`, PER
+# KEY - measured off the shipped bundle, see the probe - so a MISSING nl key
+# degrades to English and a WRONG one does not degrade at all. The card asks for
+# both languages complete, and complete is a thing a check can hold.
+check("...and the two files describe the SAME option set, so nothing on the "
+      "owner's Dutch screen quietly falls back to English",
+      set(TR["en"]["configuration"]) == set(TR["nl"]["configuration"]))
+check("...including inside the repeatable section",
+      set(TR["en"]["configuration"]["inverters"]["fields"])
+      == set(TR["nl"]["configuration"]["inverters"]["fields"]))
+check("...and no Dutch string was left as a copy of the English one, which is "
+      "what an untranslated key looks like when it is present rather than "
+      "absent",
+      not [k for k in ORDER
+           if TR["en"]["configuration"][k]["description"]
+           == TR["nl"]["configuration"][k]["description"]])
+
+print("\n3. ⭐ the description says WHETHER TO TOUCH IT")
+# ⚠️ THE HIGHEST-VALUE ITEM IN THE CARD, AND THE ONE A COVERAGE COUNT CANNOT
+# REACH. Sixty-odd descriptions that all say "the threshold, in watts" would
+# pass part 2 completely. What makes this surface safe is that a DERIVED
+# constant names the campaign it came from and says the value is not a knob,
+# while a number that really is the operator's says so too.
+#
+# ⚠️ AND THIS IS A TEXT CHECK, WHICH IS WEAK ON PURPOSE AND IS SAID TO BE. It
+# cannot know whether a citation is TRUE; it can only know that the citation is
+# there and names the right record, so that deleting the provenance - or
+# renaming the card it points at - goes red instead of shipping. The table is
+# written out rather than derived because there is nothing in config.yaml that
+# distinguishes a derived constant from an operator's number; that distinction
+# is the whole of what this card had to add.
+DERIVED = {
+    "sign_disagree_w": ("SAFETY-02", "MEASURED"),
+    "sign_disagree_s": ("SAFETY-02", "MEASURED"),
+    "unit_sign_disagree_w": ("SAFETY-30", "1890"),
+    "unit_sign_disagree_s": ("SAFETY-30", "1890"),
+    "site_sign_disagree_w": ("SAFETY-30", "CARRIED"),
+    "site_sign_disagree_s": ("SAFETY-30", "1890"),
+    "meter_freeze_s": ("SAFETY-18", "MEASURED"),
+    "circulation_w": ("SAFETY-31", "924"),
+    "circulation_hold_s": ("SAFETY-31", "DERIVED"),
+    "peak_soc_floor": ("SAFETY-24", "DERIVED"),
+    "bms_soc_floor": ("0x0560", "MEASURED"),
+    "integrator_max_w": ("MEASURED", "Do not raise it"),
+    "gain": ("MEASURED ON", "do not raise it"),
+    # SAFETY-39. `slew_w` joins the table because it stopped being an
+    # operator's convenience and became a DERIVED value the moment it was
+    # tied to the rating: 0 resolves to about a ninth of `max_w`, from an
+    # ~18 s measured step response. It is the one entry here whose value is
+    # a RATIO, so the description has to say what it follows as well as
+    # where the ratio came from - a citation alone would leave an operator
+    # reading "0" on the tab with no idea it is not "off".
+    "slew_w": ("SAFETY-39", "DERIVED", "0 MEANS FOLLOW"),
+}
+_uncited = []
+for key, needles in sorted(DERIVED.items()):
+    desc = TR["en"]["configuration"][key]["description"]
+    for needle in needles:
+        if needle not in desc:
+            _uncited.append(f"{key} does not cite {needle!r}")
+print(f"    {len(DERIVED)} derived constants must cite their campaign; "
+      f"{len(_uncited)} do not")
+check(f"every derived constant's English description names WHERE THE NUMBER "
+      f"CAME FROM, so an operator reading the tab can tell it apart from their "
+      f"own inverter rating. Uncited: {_uncited}", not _uncited)
+# The other direction, and it matters as much: a number that IS the operator's
+# must not be dressed up as derived, or the labels stop meaning anything.
+_theirs = ["max_w", "peak_cap_w"]
+check("...and the numbers that really are the OPERATOR'S say so instead of "
+      "carrying a citation - `max_w` and `peak_cap_w` are the two the card "
+      "names, and both read 'THIS IS YOUR NUMBER'",
+      all("THIS IS YOUR NUMBER" in TR["en"]["configuration"][k]["description"]
+          for k in _theirs))
+check("...and the one threshold that is NOT derived from a measurement admits "
+      "it rather than borrowing the others' authority - "
+      "`cycle_cost_threshold_eur` is an open product question (OPT-08)",
+      "NOT DERIVED FROM A MEASUREMENT"
+      in TR["en"]["configuration"]["cycle_cost_threshold_eur"]["description"]
+      and "OPT-08"
+      in TR["en"]["configuration"]["cycle_cost_threshold_eur"]["description"])
+
+print("\n4. task ordering, and the labels that carry it")
+# ⚠️ ADD-ON OPTIONS ARE A FLAT LIST - no section headers, no per-option advanced
+# flag, no units on the input. Grouping is approximated by ORDER plus label text
+# and by nothing else, so both halves are graded: the label prefix, and that the
+# prefixes appear in the file as CONTIGUOUS RUNS in the task order. A group
+# whose members are scattered renders as a jumble however good each label is.
+GROUPS = ["Hardware", "Meter", "Limits", "Tariff", "Maintenance", "Safety",
+          "Advanced"]
+NL_GROUPS = {"Hardware": "Hardware", "Meter": "Meter", "Limits": "Grenzen",
+             "Tariff": "Tarief", "Maintenance": "Onderhoud",
+             "Safety": "Veiligheid", "Advanced": "Geavanceerd"}
+_prefixes = []
+for key in ORDER:
+    name = TR["en"]["configuration"][key]["name"]
+    _prefixes.append(name.split(" \u00b7 ")[0] if " \u00b7 " in name else f"<none:{key}>")
+_runs = [p for i, p in enumerate(_prefixes) if i == 0 or p != _prefixes[i - 1]]
+print(f"    the rendered order groups into: {_runs}")
+check(f"every label carries a group prefix, so the flat list reads as groups. "
+      f"Missing: {[p for p in _prefixes if p.startswith('<none:')]}",
+      not [p for p in _prefixes if p.startswith("<none:")])
+check(f"...and each group is ONE CONTIGUOUS RUN in the rendered order, in the "
+      f"task order the card asks for - hardware, meter, ratings and limits, "
+      f"tariff, maintenance, safety, advanced. Got: {_runs}", _runs == GROUPS)
+_nl_bad = [k for k in ORDER
+           if NL_GROUPS.get(TR["en"]["configuration"][k]["name"].split(" \u00b7 ")[0])
+           != TR["nl"]["configuration"][k]["name"].split(" \u00b7 ")[0]]
+check(f"...and the Dutch labels carry the SAME grouping under Dutch names, so "
+      f"the two languages do not read as two different layouts. Off: {_nl_bad}",
+      not _nl_bad)
+# ⚠️ THE ORDER IS THE `schema:` BLOCK'S, NOT THE `options:` BLOCK'S, AND THAT IS
+# A MEASUREMENT. `App.schema_ui` is `UiOptions(coresys)(data["schema"])`, so the
+# tab renders the schema half in its own order. Asserted here because the whole
+# of part 4 is about an ordering that would otherwise be graded on the wrong
+# half of the file - and because the two halves of config.yaml were already in
+# different orders before this card.
+# ⚠️ ANCHORED ON THE INDENTATION AND SCOPED TO THE `options:` BLOCK. The file
+# starts with the add-on manifest, whose `services:` list carries `  - mqtt:want`
+# at two spaces with a colon in it - a looser reader picks that up as an option
+# called `- mqtt` and the comparison below then fails for a reason that has
+# nothing to do with what it is watching. Measured, on the first run.
+import re as _re                                                  # noqa: E402
+_opt_half = CFG_TEXT[CFG_TEXT.index("\noptions:\n"):CFG_TEXT.index("\nschema:")]
+_opt_order = _re.findall(r"^  ([a-z_0-9]+):", _opt_half, _re.M)
+check("config.yaml's two halves now declare the same options in the same "
+      "order, so the file reads the way the tab renders even though only the "
+      "schema half decides it", _opt_order == ORDER)
+
+print("\n5. the parser is strict, so a file it half-read cannot pass")
+# ⚠️ THE FAILURE THIS PART EXISTS FOR. A permissive parser answers "no problems"
+# for a file it silently skipped half of - the same green-and-not-watching
+# defect one layer down. So every shape outside the subset UX-01 writes must
+# RAISE, and that is graded with real malformed input rather than asserted.
+BAD = [
+    ("a tab-indented line", "configuration:\n\tmeter_entity:\n"),
+    ("three-space indent", "configuration:\n   meter_entity:\n"),
+    ("a bare unquoted scalar", 'configuration:\n  a:\n    name: hello\n'),
+    ("a single-quoted scalar", "configuration:\n  a:\n    name: 'hello'\n"),
+    ("a list item", 'configuration:\n  a:\n    - "x"\n'),
+    ("a duplicate key", 'configuration:\n  a:\n    name: "x"\n    name: "y"\n'),
+    ("an over-indented child", 'configuration:\n      a:\n'),
+    ("a line that is not a key at all", "configuration:\n  just some prose\n"),
+    ("an unsupported escape", 'configuration:\n  a:\n    name: "x\\ty"\n'),
+]
+_accepted = []
+for what, text in BAD:
+    try:
+        TL.parse_translation_text(text, what)
+        _accepted.append(what)
+    except TL.TranslationSyntaxError:
+        pass
+check(f"every shape outside the accepted subset RAISES rather than being "
+      f"skipped. Silently accepted: {_accepted}", not _accepted)
+check("...and the accepted subset really does round-trip the shipped files - "
+      "70 options and 7 per-entry keys came back out of each, which is what "
+      "says the strictness above is not just refusing everything",
+      all(len(TR[lg]["configuration"]) == len(ORDER)
+          and len(TR[lg]["configuration"]["inverters"]["fields"]) == 7
+          for lg in LANGS))
+print("    ⚠️ the licence for this hand parser is NOT this file. "
+      "tools/supervisor_shape_probe.py section F loads the same two files with "
+      "`supervisor.store.data._read_app_translations()` out of the 2026.08.0 "
+      "release image and asserts, key by key and string by string, that this "
+      "module returns the same thing. Re-run it when either changes.")
+
+print("\n6. MUTATION: the check is run against broken inputs, both directions")
+# ⚠️ THIS IS THE PART THE CARD ASKS FOR IN SO MANY WORDS, AND IT IS RUN RATHER
+# THAN DESCRIBED. A coverage check is worth exactly what it catches, so each
+# mutation below is APPLIED to a copy of the real parsed translations and the
+# audit is required to NAME the key it broke - not merely to be non-empty. A
+# check that goes red for the wrong reason is a check that will go green for the
+# wrong reason later.
+import copy                                                       # noqa: E402
+
+
+def _mutate(what, fn, must_name):
+    tr = copy.deepcopy(TR["en"])
+    fn(tr)
+    problems = TL.audit(CFG_TEXT, tr, "en")
+    named = [p for p in problems if must_name in p]
+    print(f"    {what}\n        -> {len(problems)} problem(s); "
+          f"{(named[0][:120] + '...') if named else 'NONE NAMED ' + must_name}")
+    check(f"MUTATION: {what} -> the audit REFUSES and names `{must_name}`",
+          bool(named))
+
+
+_mutate("delete one option's whole translation (`saturation_cycles`)",
+        lambda tr: tr["configuration"].pop("saturation_cycles"),
+        "saturation_cycles")
+_mutate("delete one option's description but keep its name (`meter_phases`)",
+        lambda tr: tr["configuration"]["meter_phases"].pop("description"),
+        "meter_phases")
+_mutate("blank one option's description (`gain`) - present but empty is not "
+        "covered either",
+        lambda tr: tr["configuration"]["gain"].update(description="   "),
+        "gain")
+_mutate("translate an option that does not exist (`saturation_cyles`, one "
+        "letter out - the rename this check exists for)",
+        lambda tr: tr["configuration"].update(
+            saturation_cyles={"name": "x", "description": "y"}),
+        "saturation_cyles")
+_mutate("delete one PER-ENTRY key of the repeatable section (`bms_soc_floor`)",
+        lambda tr: tr["configuration"]["inverters"]["fields"].pop("bms_soc_floor"),
+        "bms_soc_floor")
+_mutate("invent a per-entry key the schema does not declare (`max_kw`)",
+        lambda tr: tr["configuration"]["inverters"]["fields"].update(
+            max_kw={"name": "x", "description": "y"}),
+        "max_kw")
+_mutate("drop the whole `fields:` block from the repeatable section",
+        lambda tr: tr["configuration"]["inverters"].pop("fields"),
+        "inverters")
+_mutate("hang a `fields:` block off an option that is not a repeatable section",
+        lambda tr: tr["configuration"]["max_w"].update(
+            fields={"x": {"name": "y"}}),
+        "max_w")
+# ⚠️ AND THE TWO THAT COST THE WHOLE FILE RATHER THAN ONE LABEL. Supervisor
+# validates each translation file through SCHEMA_APP_TRANSLATIONS and, on
+# refusal, LOGS A WARNING AND DROPS ALL OF IT - so a shape it rejects does not
+# lose one description, it silently returns the entire tab to raw keys, and the
+# only trace is one line in a log nobody is reading. Neither of these is
+# reachable through the `configuration:` coverage above, which is exactly why
+# they are here.
+_mutate("a top-level block Supervisor does not read (`netwrok:`) - the file is "
+        "DROPPED WHOLE, not partly",
+        lambda tr: tr.update(netwrok={"x": "y"}), "netwrok")
+_mutate("a `network:` block whose value is a mapping rather than a string - "
+        "same consequence, every label in the file gone",
+        lambda tr: tr.update(network={"8099/tcp": {"x": "y"}}), "network")
+
+# ⚠️ AND THE MUTATION THAT MATTERS MOST: A NEW OPTION ARRIVES. This is the rot
+# the acceptance criterion is written about - somebody adds a key to config.yaml
+# in six months and the tab renders it raw. The mutation is applied to the
+# CONFIG side rather than the translation side, because that is the direction it
+# happens in.
+_grown = CFG_TEXT.replace("\n  log_level: list(", "\n  new_option_s: int(1,9)\n  log_level: list(")
+check("the config-side mutation really did land - a new option in the schema "
+      "half that no translation mentions", _grown != CFG_TEXT
+      and "new_option_s" in TL.config_surface(_grown)[0])
+_grow_problems = TL.audit(_grown, TR["en"], "en")
+print(f"    a new option added to config.yaml -> {_grow_problems[:1]}")
+check("MUTATION: adding an option to config.yaml and forgetting the "
+      "translation goes RED, naming the key - which is the whole of the "
+      "acceptance criterion about this rotting",
+      any("new_option_s" in p for p in _grow_problems))
+
+# ⚠️ THE NEGATIVE CONTROL, WITHOUT WHICH THE EIGHT ROWS ABOVE PROVE NOTHING. An
+# audit that returned a problem for every input would have "passed" all of them.
+check("...and the UNMUTATED input is still clean, so the rows above are the "
+      "mutations speaking and not a check that always complains",
+      not TL.audit(CFG_TEXT, TR["en"], "en")
+      and not TL.audit(CFG_TEXT, TR["nl"], "nl"))
+
+print("\n7. no behaviour and no value moved")
+# ⚠️ UX-01 IS A PRESENTATION CARD. It reorders config.yaml and adds two files;
+# it must not move a single default. The whole options half is compared against
+# the schema half key by key here, and every other suite in this directory pins
+# the actual values by reading this same file - test_maintenance.py's eight,
+# test_watchdog.py's six, test_price.py's seven, test_freeze.py's, and
+# test_peakguard.py's. This line is the cheap one that says the reorder did not
+# lose or duplicate a key on the way.
+check("no option was lost, gained or duplicated by the reordering: the two "
+      "halves of config.yaml hold the same 70 keys, once each",
+      sorted(_opt_order) == sorted(ORDER) and len(set(ORDER)) == len(ORDER))
+check("...and `inverters: []` is still shipped in the options half, which is "
+      "what Supervisor 2026.08.0 refuses every pre-0.6.0 options blob without "
+      "(measured; see DECISIONS/CFG-04-inverter-roster.md B)",
+      "\n  inverters: []\n" in _opt_half)
+check("...and the schema half still declares the NESTED per-entry `max_w:` "
+      "BEFORE the flat one, so test_inverter.py part 12's first-match trap "
+      "stays baited rather than sorted out by this card's reordering",
+      CFG_TEXT[CFG_TEXT.index("\nschema:"):].index("      max_w: int(")
+      < CFG_TEXT[CFG_TEXT.index("\nschema:"):].index("\n  max_w: int("))
+
+print()
+if FAILED:
+    print(f"{FAILED} FAILED")
+    sys.exit(1)
+print("all checks passed")

goodwe_controller/test_validate.py

@@ -18,9 +18,10 @@ import asyncio
 import sys
 
 from app.maintenance import MAINT_OPTION_DEFAULTS, MaintConfig
+from app.control import LOOP_TICK_S, PLANT_SETTLE_S, SLEW_RAIL_FRAC
 from app.validate import (
     ACTUATOR_WRITE_KEYS, FIRMWARE_INGEST_VETO_S, ConfigRefused,
-    actuator_writers, refuse, validate_startup_config,
+    actuator_writers, refuse, site_rail_w, validate_startup_config,
 )
 
 fails = []
@@ -204,12 +205,17 @@ check("...and the refusal names the actuator and every writer aimed at it, so "
 _PER_INVERTER_OK = {k: v for k, v in base().items() if k != "setpoint_entity"}
 _PER_INVERTER_OK["inverters"] = [
     {"name": "inverter-a", "setpoint_entity": "number.goodwe_setpoint",
-     "max_w": 2000},
+     "max_w": 2000, "bms_soc_floor": 10},
     # ⚠️ INVERTER B DOES NOT EXIST. 2000 W here is the SHIPPED default repeated,
     # not a rating measured off a second device - SPIKE-04 measures that when
     # there is one to measure. Nothing in this file depends on the number.
+    # ⚠️ SAFETY-32 made `bms_soc_floor` a REQUIRED per-entry key, and the two
+    # values here DIFFER (10 / 15) rather than being copied. 15 % is SIMULATED -
+    # there is no second pack to read a cut-out off - and the reason it is not
+    # simply 10 is MUTATION.md habit 1: a fixture whose two per-unit numbers are
+    # equal cannot show a check reading the wrong unit's.
     {"name": "inverter-b", "setpoint_entity": "number.goodwe_setpoint_b",
-     "max_w": 2000}]
+     "max_w": 2000, "bms_soc_floor": 15}]
 check("two inverters with their own entities are ACCEPTED - one writer each, "
       "no shared actuator, and that is CFG-04's whole purpose",
       validate_startup_config(_PER_INVERTER_OK, -5000, 5000) == [])
@@ -452,6 +458,149 @@ check("arbiter: the drain SET is clamped, not contradicted",
 check("...and the clamp names itself, which is why it is not refused",
       "supervised" in (r.bound_by or "") and "limited by" in r.explain())
 
+# --------------------------------------------------------------------------- #
+print("10. a slew rate the plant can actually follow (SAFETY-39)")
+# ⚠️ THIS RULE GRADES A RELATIONSHIP, WHICH IS THE POINT OF IT. Every other rule
+# in this file compares a configured number against another configured number
+# and refuses one ordering. This one refuses a RATIO: `slew_w` may not exceed
+# `SLEW_RAIL_FRAC * rail`, so the same `slew_w` is fine at one rating and
+# refused at another, and raising the rating moves the bound with it instead of
+# leaving the constant behind. That is the failure the ticket is about -
+# `slew_w: 1000` was derived at a 1500 W clamp, the live install went to 5000,
+# and nothing anywhere said the derivation no longer held.
+print(f"    SLEW_RAIL_FRAC = LOOP_TICK_S / PLANT_SETTLE_S = "
+      f"{LOOP_TICK_S:.0f} s / {PLANT_SETTLE_S:.0f} s = {SLEW_RAIL_FRAC:.4f}")
+
+_R5000 = base(max_w=5000, maintenance_charge_w=2000, maintenance_discharge_w=2000)
+check("the rail this rule grades is the SITE rail, and at the shipped roster of "
+      "one it is `max_w` exactly - byte for byte the number the single-inverter "
+      "shape has always meant",
+      site_rail_w(_R5000) == 5000.0)
+
+# ⭐ VERIFIED BY BREAKING IT. This is the acceptance criterion stated as a test:
+# put the 2026-09-05 pair back and the gate must go red. A rule that could not
+# be made to fire on the configuration it was written for is a rule nobody has
+# checked.
+_broken = validate_startup_config(dict(_R5000, slew_w=1000), -5000, 5000)
+print(f"    restoring slew_w 1000 at max_w 5000 -> {len(_broken)} problem(s)")
+if _broken:
+    print(f"      {_broken[0][:160]}...")
+check("⭐ RESTORING THE 2026-09-05 PAIR - slew_w 1000 at max_w 5000 - IS REFUSED. "
+      "It crosses the whole output range in 10 s against a plant measured at "
+      "18 s, which is not a fast loop, it is a loop that commands its entire "
+      "range before it can observe its answer to the first step",
+      len(_broken) == 1 and why(_broken, "slew_w is 1000 W"))
+check("...and the refusal says WHICH RAIL it graded against and HOW LONG the "
+      "crossing takes, because 'slew_w is too high' sends an operator to lower "
+      "a number when raising max_w or setting 0 are both correct answers too",
+      why(_broken, "site rail of 5000 W")
+      and why(_broken, "crosses its whole output range in 5.0 cycles"))
+check("...and it names the plant measurement it is graded against, so the "
+      "number is traceable to a step response rather than to a preference",
+      why(_broken, "goodwe/NOTES.md §5.10"))
+check("...and it says what to DO, including the setting that cannot go stale",
+      why(_broken, "Set slew_w to 0") and why(_broken, "556 W"))
+
+# THE BOUNDARY. Equality is the DERIVED VALUE, not a violation - at exactly
+# `SLEW_RAIL_FRAC * rail` the loop takes precisely the plant's settling time to
+# cross its range, which is the constraint met. Rule 6 permits equality for the
+# same shape of reason and rule 5 refuses it for the opposite one; this is
+# rule 6's case, and getting it backwards would refuse the value this rule
+# exists to recommend.
+_bound = SLEW_RAIL_FRAC * 5000.0
+check(f"at exactly the derived value ({_bound:.0f} W) the config STARTS - "
+      "equality is the constraint satisfied, not violated",
+      validate_startup_config(dict(_R5000, slew_w=int(_bound)), -5000, 5000) == [])
+check("...and one watt of slack above it starts too, because a boundary that "
+      "is not meaningful to one watt must not refuse on one watt - an operator "
+      "reading 556 off a status page that rounded it is not misconfigured",
+      validate_startup_config(dict(_R5000, slew_w=556), -5000, 5000) == [])
+check("...and well above it does not", 
+      validate_startup_config(dict(_R5000, slew_w=600), -5000, 5000) != [])
+
+# SLOWER IS ALWAYS ACCEPTED, and the live install is the reason it has to be.
+check("the interim that is holding on the live system - slew_w 400 against "
+      "max_w 5000, applied 2026-09-05 12:00 - STARTS. It is 12.5 ticks to cross "
+      "the rail against the 9 this rule requires, and refusing 'too slow' would "
+      "refuse the mitigation",
+      validate_startup_config(dict(_R5000, slew_w=400), -5000, 5000) == [])
+check("...and so does the schema floor at the biggest rail, because there is no "
+      "such thing as too slow here",
+      validate_startup_config(dict(_R5000, slew_w=50), -5000, 5000) == [])
+
+# ⚠️ 0 IS NOT GRADED AND MUST NOT BE. It means "follow the rail" and satisfies
+# this rule by construction at every rail there is; a rule that refused it would
+# refuse the fix. Checked at three ratings so that "it passes" cannot be an
+# accident of the default one.
+# ⚠️ NO SLEW PROBLEM AT ANY RATING, rather than NO PROBLEMS AT ALL. At the
+# schema floor of 100 W rules 5 and 5b fire on the shipped sign thresholds,
+# which is correct and is not this rule's business - asserting an empty list
+# would make this check fail for a reason it is not about, and somebody would
+# then "fix" it by moving a sign threshold.
+_zero_problems = {m: [p for p in validate_startup_config(
+                          base(max_w=m, slew_w=0,
+                               maintenance_charge_w=min(2000, m),
+                               maintenance_discharge_w=min(2000, m)),
+                          -abs(m), abs(m)) if "slew_w" in p]
+                  for m in (100, 500, 2000, 5000, 15000)}
+check("slew_w 0 - FOLLOW THE RAIL - is never refused at any rating, which it "
+      "must not be, because it is the shipped value and it satisfies this rule "
+      f"by construction at every rail there is: {_zero_problems}",
+      not any(_zero_problems.values()))
+check("a negative slew_w is refused as nonsense rather than treated as 0 - it "
+      "is a magnitude, and 0 already has a meaning here",
+      why(validate_startup_config(dict(_R5000, slew_w=-400), -5000, 5000),
+          "must not be negative"))
+
+# ⭐ THE ROSTER, WHICH IS THE WHOLE REASON THIS GRADES A SUM. `slew_w` is not a
+# per-unit quantity: main.py builds `Tuning(max_w=self.site_max_w)` and
+# `compute()` emits the SITE target. So the rail is the roster sum, and adding
+# an inverter moves this bound with no operator action and no second derivation.
+#
+# ⚠️ INVERTER B'S 4600 W IS ITS DATASHEET AND SERIAL, NOT A MEASUREMENT, AND
+# INVERTER B IS NOT ON SITE (SPIKE-04, ~2026-09-12; goodwe/NOTES.md §1.1b). It
+# is used here because what is graded is the ARITHMETIC OF THE RULE, which does
+# not depend on the number being measured - not because 9600 W is a fact about
+# this house yet.
+def _roster(a=5000, b=4600, **over):
+    o = base(setpoint_entity="", inverters=[
+        {"name": "inverter-a", "setpoint_entity": "number.a", "max_w": a,
+         "bms_soc_floor": 10, "soc_entity": "sensor.sa", "batt_entity": "sensor.ba"},
+        {"name": "inverter-b", "setpoint_entity": "number.b", "max_w": b,
+         "bms_soc_floor": 10, "soc_entity": "sensor.sb", "batt_entity": "sensor.bb"}])
+    o.pop("max_w"); o.pop("soc_entity"); o.pop("batt_entity")
+    o.update(over)
+    return o
+
+
+_site = site_rail_w(_roster())
+print(f"    roster 5000 + 4600 (B FROM DATASHEET, NOT MEASURED) -> site rail "
+      f"{_site:.0f} W, bound {SLEW_RAIL_FRAC * _site:.0f} W")
+check("the rail is the roster SUM and not the weakest unit, which is what "
+      "separates this rule from 5, 6 and 8 - those grade one watchdog, one "
+      "shaping claim and one pack, and this grades the range one SITE COMMAND "
+      "is a rate across",
+      _site == 9600.0)
+check("⭐ AND THE BOUND MOVES ON ITS OWN WHEN THE ROSTER DOES: the derived value "
+      "at a 9600 W site is 1067 W with nobody re-deriving anything, which is "
+      "the property that makes this a fix rather than a re-tune",
+      abs(SLEW_RAIL_FRAC * _site - 9600.0 / 9.0) < 1e-9)
+check("...so the same explicit slew_w that is REFUSED at a 5000 W rail is "
+      "ACCEPTED at 9600 - the bound is on how long the crossing TAKES, and a "
+      "bigger rail at the same step size takes longer to cross. ⚠️ This is the "
+      "direction of the rule stated as a test, because it is not the direction "
+      "the ticket assumed: a growing rail LOOSENS this bound. What the rule "
+      "protects against is the constant being left behind when the rail moves; "
+      "it is not a bound on how much the site may command, and it does not "
+      "bound the over-absorption, which is a `gain` term SAFETY-39 measured "
+      "and deliberately did not change",
+      validate_startup_config(dict(_R5000, slew_w=1000), -5000, 5000) != []
+      and validate_startup_config(_roster(slew_w=1000)) == [])
+check("...and a slew that outruns even the doubled rail is still refused there, "
+      "so the roster path is not simply un-graded",
+      why(validate_startup_config(_roster(slew_w=2000)),
+          "site rail of 9600 W"))
+
 # --------------------------------------------------------------------------- #
 print("the SHIPPED defaults must pass the rule they are governed by (AC3)")
 # ⚠️ Shipping a default the validator refuses would be worse than the bug it
@@ -465,12 +614,21 @@ import re                                   # noqa: E402
 _CFG = os.path.join(os.path.dirname(os.path.abspath(__file__)), "config.yaml")
 with open(_CFG, encoding="utf-8") as _fh:
     _txt = _fh.read()
+# ⚠️ `slew_w` JOINED THIS SET AT SAFETY-39 AND IT IS THE INTERESTING MEMBER.
+# The others are refused when they are too big for `max_w`; this one is refused
+# when it is too big for `max_w` AS A RATIO, so shipping the wrong number here
+# would be shipping the exact defect the card is about with the gate that
+# catches it standing right beside it. Reading it out of config.yaml is what
+# makes "the shipped value is 0" a fact rather than a claim.
 _shipped = {k: float(v) for k, v in re.findall(
-    r"^  (max_w|maintenance_charge_w|maintenance_discharge_w|sign_disagree_w): "
-    r"(-?\d+(?:\.\d+)?)\s*$", _txt, re.M)}
-check("config.yaml really was read (all four defaults found)",
+    r"^  (max_w|maintenance_charge_w|maintenance_discharge_w|sign_disagree_w"
+    r"|slew_w): (-?\d+(?:\.\d+)?)\s*$", _txt, re.M)}
+check("config.yaml really was read (all five defaults found)",
       set(_shipped) == {"max_w", "maintenance_charge_w",
-                        "maintenance_discharge_w", "sign_disagree_w"})
+                        "maintenance_discharge_w", "sign_disagree_w", "slew_w"})
+check(f"...and the shipped slew_w is 0, i.e. FOLLOW THE RAIL - the one value "
+      f"that cannot be left behind when max_w moves (got {_shipped.get('slew_w')})",
+      _shipped.get("slew_w") == 0.0)
 check(f"the shipped defaults are accepted {_shipped}",
       validate_startup_config(base(**_shipped), -5000, 5000) == [])
 check("...and the shipped charge rate is at or under the shipped ceiling",
@@ -828,6 +986,339 @@ check("...and MaintConfig's dataclass defaults carry no numeric literal either "
       not re.search(r"^\s*(charge_w|discharge_w):\s*float\s*=\s*-?\d",
                     _srcs["maintenance.py"], re.M))
 
+# --------------------------------------------------------------------------- #
+print("SPIKE-04a: inverter B's documented rating, and the provenance beside it")
+# ⚠️ WHY A DOCUMENTATION CARD LEFT A CHECK BEHIND. Inverter B's rating was
+# written down in THREE places - config.yaml's commented roster example,
+# DOCS.md's, and tools/supervisor_shape_probe.py's "a blob an operator would
+# POST" - as 3000 W, a figure nobody had measured, read off a datasheet, or
+# sourced at all. It was wrong: SPIKE-04a (2026-09-04) identified inverter B
+# from the owner's model number and serial as a GoodWe GW5048D-ES rated 4600 W
+# on the battery path. Three transcriptions of one number drifting away from
+# the truth together is this repo's recurring defect in its plainest form, and
+# correcting them once WITHOUT PINNING THEM buys nothing: the next editor
+# touches one of the three and the other two stay wrong, silently.
+#
+# ⚠️ AND THE PROVENANCE IS GRADED, NOT ONLY THE VALUE, WHICH IS THE HALF THAT
+# MATTERS. 4600 W IS FROM A DATASHEET AND IS NOT A MEASUREMENT. The datasheet
+# prints it under BATTERY INPUT DATA, so it is probably DC, while `max_w` is
+# graded against 0x0518 - the inverter's own AC power - which would put the AC
+# ceiling nearer 4324 W. An editor who tidies that caveat away leaves a paper
+# number reading as an observation of hardware that does not exist yet, and
+# THAT is the failure this card exists to prevent. So the caveat is what these
+# checks reach for; a check that graded 4600 alone would watch the value and
+# miss the lie.
+#
+# ⚠️ WHAT THIS DELIBERATELY DOES NOT GRADE: the test fixtures. Several files
+# build a second inverter at 3000 W on purpose, because the property those
+# checks consume is that B's rating is UNMISTAKABLY not A's, and the real pair
+# (5000/4600) is a 400 W gap - narrower than `slew_w`. Those are illustrative,
+# they say so at the line, and they are not statements of B's rating. The three
+# sites below are the ones that ARE such statements.
+_HERE = os.path.dirname(os.path.abspath(__file__))
+_docs_txt = open(os.path.join(_HERE, "DOCS.md"), encoding="utf-8").read()
+_probe_txt = open(os.path.join(_HERE, "tools", "supervisor_shape_probe.py"),
+                  encoding="utf-8").read()
+
+# One regex per site, each anchored on something only THAT site has, so a match
+# cannot silently wander into a neighbouring blob. The probe's anchor is the
+# operator blob's real entity name: its section D refusal entries use
+# `number.b` and one of them carries a deliberate 9999, so an anchor loose
+# enough to reach them would grade the wrong dict and still look green.
+_b_rating = {
+    "config.yaml": re.search(
+        r"#\s+- name: inverter-b\b(?:[^\n]*\n)*?\s*#\s+max_w:\s*(\d+)", _txt),
+    "DOCS.md": re.search(
+        r"^  - name: inverter-b\b(?:[^\n]*\n)*?^    max_w:\s*(\d+)",
+        _docs_txt, re.M),
+    "supervisor_shape_probe.py": re.search(
+        r'"name": "inverter-b",\s*"setpoint_entity": "number\.goodwe_b_setpoint_w"'
+        r'(?:[^}]*?)"max_w":\s*(\d+)', _probe_txt),
+}
+check(f"all three documented rosters were FOUND "
+      f"{ {k: bool(v) for k, v in _b_rating.items()} } - a regex that matches "
+      "nothing is a green check that read nothing",
+      all(_b_rating.values()))
+# ⚠️ THE `len(...) == 3` IS NOT DECORATION. Without it a regex that stopped
+# matching would shrink this dict, and "all the values agree" would go GREEN on
+# the two sites that were still read - a check whose data no longer reaches the
+# failure it names, which is the exact fault this whole section is about.
+_b_vals = {k: int(m.group(1)) for k, m in _b_rating.items() if m}
+check(f"...and all three state the SAME rating for inverter B {_b_vals}",
+      len(_b_vals) == 3 and len(set(_b_vals.values())) == 1)
+check(f"...and it is 4600 W - the GW5048D-ES datasheet figure, not the 3000 W "
+      f"hypothesis that predated the unit being identified {_b_vals}",
+      len(_b_vals) == 3 and set(_b_vals.values()) == {4600})
+
+# The provenance triple. Each site must still say WHERE 4600 came from, that it
+# is graded against an AC register, and what the DC-vs-AC ambiguity does to it -
+# the last carried by the 4324 W figure, which is the one marker that cannot
+# survive a careless "it's 4600 now, done" rewrite.
+#
+# ⚠️ SEARCHED IN A WINDOW AROUND THE ROSTER, NOT OVER THE WHOLE FILE, AND THE
+# FIRST VERSION OF THIS CHECK DID THE LATTER. `0x0518` already appeared once in
+# config.yaml and once in DOCS.md before this card, for unrelated reasons - so a
+# whole-file `"0x0518" in src` was GREEN on those two files no matter what
+# happened next to inverter B's rating. That is a check whose data cannot reach
+# the failure it names, in the same file that exists to complain about them.
+# The window is the text either side of the roster match, so deleting the caveat
+# beside the number goes red even where the same word survives elsewhere.
+_sites = {"config.yaml": _txt, "DOCS.md": _docs_txt,
+          "supervisor_shape_probe.py": _probe_txt}
+_MARKERS = ("datasheet", "0x0518", "4324")
+_prov = {}
+for _name, _src in _sites.items():
+    _m = _b_rating[_name]
+    _win = _src[max(0, _m.start() - 2500):_m.end() + 2500].lower() if _m else ""
+    _prov[_name] = {k: k in _win for k in _MARKERS}
+for _name, _got in sorted(_prov.items()):
+    check(f"{_name} still carries B's provenance WITHIN 2500 chars of the "
+          f"roster - the datasheet it came from, the 0x0518 it is graded "
+          f"against, and the 4324 W the DC reading would make it {_got}",
+          all(_got.values()))
+
+
+# --------------------------------------------------------------------------- #
+print("rules 5, 5b and 6 on a ROSTER SET - the smallest cap at EVERY position")
+# ⚠️ SAFETY-32 ROUND 5, AND THE REASON THIS SECTION EXISTS AT ALL. PR #48 was
+# rejected on FOUR MUTATIONS THAT SURVIVED A 19/19 GREEN SUITE, all of them in
+# the three lines above:
+#
+#   validate.py:779  min(caps)   -> min(caps[:1])                  +4 B  GREEN
+#   validate.py:779  min(caps)   -> min(caps[-1:])                 +5 B  GREEN
+#   validate.py:778  caps = [cap for _, cap in caps_ix[:1]]        +4 B  GREEN
+#   validate.py:893  min(caps_ix[-1:], key=lambda p: p[1])         +5 B  GREEN
+#
+# NONE of them is an equivalent mutant: each one deletes a safety refusal.
+# `max_w: 5000` on inverter-a beside `2000` on inverter-b with
+# `sign_disagree_w: 3000` is refused by the shipped validator with "the
+# SAFETY-02 sign-disagreement watchdog can never fire" and ACCEPTED by every one
+# of the four - the site starts, with a watchdog that reports `armed` on the
+# status page and cannot trip on pack B. That is rule 5's own failure mode
+# reached THROUGH rule 5.
+#
+# WHY THE OLD FIXTURE COULD NOT SEE IT, which is the whole lesson and is now
+# MUTATION.md habit 10: the fixture was ONE roster, `[5000, 2000]`. On that
+# roster `min` and `last` and `[-1:]` and `[:2]` all answer 2000. A fixture of N
+# members cannot separate two reductions that agree on N members, and adding a
+# member moves the hole instead of closing it.
+#
+# SO THE FIXTURE IS A SET, NOT A ROSTER: the smallest cap at EVERY POSITION of
+# rosters of width 2, 3, 4 and 5. `[:1]` needs width 2 to be caught, `[:2]`
+# needs 3, `[:3]` needs 4 - the sweep is what terminates the regress that a
+# single fixture cannot. And the FAMILY TABLE below is COMPUTED AND PRINTED, so
+# a member no fixture kills shows up as a NAMED SURVIVOR rather than as an
+# absence from a list nobody re-derived.
+#
+# ⚠️ THE DIFFERING CAPS ARE A FIXTURE PROPERTY AND MUST STAY ONE. In production
+# both packs are expected to floor at 10 % and SPIKE-04a puts inverter B at
+# 4600 W against A's 5000 W - a 400 W gap, narrower than slew_w. A fixture built
+# on the real pair would be degenerate on exactly the axis these checks measure.
+# ⚠️ AND INVERTER B DOES NOT PHYSICALLY EXIST (SPIKE-04, ~2026-09-12). Nothing
+# in this section is measured off a second unit; the rosters are simulated and
+# are labelled so.
+_BIG, _SMALL = 5000.0, 2000.0
+_RATE = 3000.0                     # strictly between them, which is the point
+
+
+def _roster_n(caps, **over):
+    """A roster of len(caps) units, unit-0..unit-N, each with its own cap."""
+    o = base(**over)
+    for k in ("setpoint_entity", "soc_entity", "batt_entity", "max_w"):
+        o.pop(k, None)
+    o["inverters"] = [
+        dict(name=f"unit-{i}", setpoint_entity=f"number.sp{i}",
+             soc_entity=f"sensor.soc{i}", batt_entity=f"sensor.batt{i}",
+             max_w=c, bms_soc_floor=10)
+        for i, c in enumerate(caps)]
+    o.update(over)
+    return o
+
+
+# The three rules that reduce over `unit_caps_indexed()`, each as
+# (option name, the token its refusal is recognised by).
+_CAP_RULES = (
+    ("sign_disagree_w", "SAFETY-02 sign-disagreement"),
+    ("unit_sign_disagree_w", "SAFETY-30 per-inverter sign-disagreement"),
+    ("maintenance_charge_w", "maintenance charge in a cheap window"),
+)
+_QUIET = {"sign_disagree_w": 300.0, "unit_sign_disagree_w": 300.0,
+          "maintenance_charge_w": 1000.0, "maintenance_discharge_w": 1000.0}
+
+# THE SET: width x position of the one small cap.
+_SET = []
+for _n in (2, 3, 4, 5):
+    for _pos in range(_n):
+        _caps = [_BIG] * _n
+        _caps[_pos] = _SMALL
+        _SET.append((_n, _pos, tuple(_caps)))
+
+# habit 1: the PRECONDITION as its own check. If a later edit makes the caps
+# equal, this goes red rather than the claims below going quietly vacuous.
+check("PRECONDITION: every fixture in the set has a UNIQUE smallest cap, that "
+      "cap is at the stated position, and the rate under test sits STRICTLY "
+      "between it and the others - two equal caps could not tell `min` from "
+      "`first` from `last` and the whole set would be measuring nothing",
+      len(_SET) == 14
+      and all(c[p] == _SMALL and c.count(_SMALL) == 1 and _SMALL < _RATE < _BIG
+              for _n2, p, c in _SET)
+      and {p for _n2, p, _c in _SET} == {0, 1, 2, 3, 4})
+
+
+def _verdict(opts, token):
+    """(refused?, the unit the message NAMES, the cap it QUOTES)."""
+    ps = [p for p in validate_startup_config(opts, -5000, 5000) if token in p]
+    if not ps:
+        return (False, None, None)
+    m = re.search(r"max_w \(([^)]+)\) is (\d+) W", ps[0])
+    return (True, m.group(1) if m else None, float(m.group(2)) if m else None)
+
+
+# --- the shipped answer, on every member of the set -------------------------
+_rows = []
+for _opt, _token in _CAP_RULES:
+    for _n, _pos, _caps in _SET:
+        _o = _roster_n(list(_caps), **dict(_QUIET, **{_opt: _RATE}))
+        _rows.append((_opt, _n, _pos, _caps, _verdict(_o, _token)))
+print(f"    {len(_CAP_RULES)} rules x {len(_SET)} rosters = {len(_rows)} runs "
+      f"of the REAL validator (rate {_RATE:.0f} W, caps {_SMALL:.0f}/"
+      f"{_BIG:.0f} W, simulated rosters - inverter B does not exist):")
+for _opt in sorted({r[0] for r in _rows}):
+    _got = [(r[1], r[2], r[4]) for r in _rows if r[0] == _opt]
+    print(f"      {_opt:<22} " + " ".join(
+        f"n{n}p{p}:{'REFUSE ' + str(u) if ok else 'starts'}"
+        for n, p, (ok, u, _c) in _got))
+
+check("⚠️ EVERY ONE OF THE THREE CAP RULES REFUSES ON EVERY MEMBER OF THE SET, "
+      "and NAMES THE UNIT THE NUMBER CAME OFF - at width 2, 3, 4 and 5, with "
+      "the small cap at every position in turn. A reduction that answered "
+      "`first`, `last`, `[:1]`, `[-1:]`, `[:2]` or `[:-1]` instead of `min` "
+      "misses at least one member of this set, which is what four hand-run "
+      "mutations against a 19/19 green suite proved the single `[5000, 2000]` "
+      "fixture could not do",
+      all(ok and unit == f"unit-{p}" and cap == _SMALL
+          for _o2, _n2, p, _c2, (ok, unit, cap) in _rows))
+
+check("...and it is a COMPARISON, not a blanket refusal of rosters: the same "
+      "three rates against a roster whose caps can ALL take them start "
+      "cleanly, at every width. Without this the line above is satisfied by a "
+      "validator that refuses everything (habit 2 in the negative direction)",
+      all(_verdict(_roster_n([_BIG] * n, **dict(_QUIET, **{opt: _RATE})),
+                   tok) == (False, None, None)
+          for opt, tok in _CAP_RULES for n in (1, 2, 3, 4, 5)))
+
+# --- the POSITIONAL-SLICE FAMILY TABLE, computed and printed ----------------
+# ⚠️ COMPUTED, NOT LISTED. Each candidate is applied to the SAME caps the
+# validator saw, and its (unit, cap) answer is compared against what the shipped
+# validator actually said on that roster. A candidate that agrees everywhere is
+# a reduction this fixture set CANNOT distinguish from the shipped one, and it
+# is printed as a SURVIVOR rather than left out of a table nobody re-derived.
+def _pick(caps, fn):
+    ix = list(enumerate(caps))
+    try:
+        i, c = fn(ix)
+    except (ValueError, IndexError):
+        return None
+    return (f"unit-{i}", c)
+
+
+_FAMILY = {
+    "min (SHIPPED)":  lambda ix: min(ix, key=lambda p: p[1]),
+    "max":            lambda ix: max(ix, key=lambda p: p[1]),
+    "first":          lambda ix: ix[0],
+    "last":           lambda ix: ix[-1],
+    "min(caps[:1])":  lambda ix: min(ix[:1], key=lambda p: p[1]),
+    "min(caps[-1:])": lambda ix: min(ix[-1:], key=lambda p: p[1]),
+    "min(caps[:2])":  lambda ix: min(ix[:2], key=lambda p: p[1]),
+    "min(caps[:3])":  lambda ix: min(ix[:3], key=lambda p: p[1]),
+    "min(caps[1:])":  lambda ix: min(ix[1:], key=lambda p: p[1]),
+    "min(caps[:-1])": lambda ix: min(ix[:-1], key=lambda p: p[1]),
+    "min(caps[::2])": lambda ix: min(ix[::2], key=lambda p: p[1]),
+    "mean":           lambda ix: (0, sum(c for _i, c in ix) / len(ix)),
+}
+_survivors = []
+print("    the family table - each candidate against what the SHIPPED "
+      "validator answered on the same roster:")
+for _name, _fn in _FAMILY.items():
+    _misses = []
+    for _opt, _n, _pos, _caps, (_ok, _unit, _cap) in _rows:
+        _pred = _pick(list(_caps), _fn)
+        _pred_refuses = _pred is not None and _pred[1] > 0 and _RATE >= _pred[1]
+        if _opt == "maintenance_charge_w":
+            _pred_refuses = (_pred is not None and _pred[1] > 0
+                             and _RATE > _pred[1])
+        _said = ((True, _pred[0], _pred[1]) if _pred_refuses
+                 else (False, None, None))
+        if _said != (_ok, _unit, _cap):
+            _misses.append(f"{_opt[:4]}/n{_n}p{_pos}")
+    if not _misses and _name != "min (SHIPPED)":
+        _survivors.append(_name)
+    print(f"      {_name:<16} {'AGREES EVERYWHERE (survivor)' if not _misses else 'differs on ' + str(len(_misses)) + ' run(s), first: ' + _misses[0]}")
+check("⚠️ AND THE FAMILY TABLE HAS NO SURVIVOR BUT THE SHIPPED REDUCTION. "
+      "Eleven candidates - max, first, last, the mean, and every positional "
+      "slice this card has actually been defeated by - are each computed "
+      "against what the real validator answered on the same roster, and every "
+      "one of them differs somewhere in the set. This is the check that would "
+      "have taken PR #48 red four rounds ago: a member no fixture kills is "
+      "PRINTED AS A NAMED SURVIVOR here instead of being absent from a list "
+      f"nobody re-derived. survivors: {_survivors}",
+      _survivors == [])
+
+# --- the ROSTER OF ONE, where every one of them is the same thing -----------
+_at_one = {n: _pick([_SMALL], f) for n, f in _FAMILY.items()}
+print(f"    at a ROSTER OF ONE the twelve candidates answer: "
+      f"{sorted({str(v) for v in _at_one.values()})}")
+check("...and at a ROSTER OF ONE every candidate that still has a member to "
+      "reduce answers THE SAME THING - which is exactly why no "
+      "single-inverter fixture in this repository could ever have caught any "
+      "of this, and why the shipped single-inverter refusals are what they "
+      "always were. The only two that do NOT coincide are `caps[1:]` and "
+      "`caps[:-1]`, which EMPTY the list and would raise: at N=1 they are "
+      "crashes rather than silent wrong answers, so they are not survivors "
+      "there either",
+      {v for v in _at_one.values() if v is not None} == {("unit-0", _SMALL)}
+      and {n for n, v in _at_one.items() if v is None}
+      == {"min(caps[1:])", "min(caps[:-1])"}
+      and _verdict(_roster_n([_SMALL], **dict(_QUIET, sign_disagree_w=_RATE)),
+                   "SAFETY-02 sign-disagreement")[0])
+
+# --- rule 5's SIBLING BRANCH, which was reading the FLAT max_w --------------
+# ⚠️ FOUND BY READING THE THREE BRANCHES SIDE BY SIDE, NOT BY THE STRUCTURAL
+# PIN - and said that way on purpose, because it is the shape of what the pin
+# cannot see. `unit_sign_disagree_w` is SAFETY-30's, not this card's. It was
+# graded against `_number(opts, "max_w", 2000.0)`, the FLAT option, three lines
+# under a branch that had already stopped doing that. Both directions were
+# measured before the fix and both are asserted here.
+_leftover = _roster_n([_SMALL, _SMALL],
+                      **dict(_QUIET, unit_sign_disagree_w=_RATE))
+_leftover["max_w"] = _BIG          # what a single-inverter install leaves behind
+_lv = _verdict(_leftover, "SAFETY-30 per-inverter sign-disagreement")
+print(f"    leftover flat max_w {_BIG:.0f} beside a roster of two "
+      f"{_SMALL:.0f} W units, unit_sign_disagree_w {_RATE:.0f} -> {_lv}")
+check("⚠️ A LEFTOVER FLAT `max_w` NO LONGER DISARMS SAFETY-30's PER-UNIT "
+      "WATCHDOG SILENTLY. Two 2000 W units beside a `max_w: 5000` left over "
+      "from a single-inverter install and `unit_sign_disagree_w: 3000` used to "
+      "produce ZERO problems - the site started, the status page said `armed`, "
+      "and the watchdog could not trip on EITHER unit. It is refused now, "
+      "against the weakest unit's own cap, and the message names that unit",
+      _lv == (True, "unit-0", _SMALL))
+check("...and the over-refusal in the OTHER direction is gone too: a roster of "
+      "two 5000 W units with NO flat `max_w` was refused at 3000 W against a "
+      "2000 W DEFAULT the operator never wrote, for a threshold both units can "
+      "reach. It starts",
+      _verdict(_roster_n([_BIG, _BIG],
+                         **dict(_QUIET, unit_sign_disagree_w=_RATE)),
+               "SAFETY-30 per-inverter sign-disagreement")
+      == (False, None, None))
+check("...and the flat single-inverter config it always refused is refused "
+      "IDENTICALLY - `unit_caps()` at a roster of one is `[max_w]`, so this is "
+      "the same comparison, the same boundary and the same sentence",
+      why(validate_startup_config(base(max_w=2000, unit_sign_disagree_w=2000),
+                                  -5000, 5000), "unit_sign_disagree_w")
+      and validate_startup_config(base(max_w=2000, unit_sign_disagree_w=1999),
+                                  -5000, 5000) == [])
+
+
 # --------------------------------------------------------------------------- #
 print()
 if fails:

goodwe_controller/test_watchdog.py

@@ -798,9 +798,18 @@ print("   circulation the allocator NEVER COMMANDED")
 
 from app.inverter import Inverter  # noqa: E402
 
-# ⚠️ INVERTER B DOES NOT PHYSICALLY EXIST - it is ~10 days out and SPIKE-04
-# measures it. Its rating here is a HYPOTHESIS, named as one, exactly as
-# test_peakguard.py's helper names its own.
+# ⚠️ INVERTER B DOES NOT PHYSICALLY EXIST - it is ~8 days out (2026-09-04) and
+# the bench half of SPIKE-04 measures it.
+# ⚠️ SPIKE-04a (2026-09-04) ESTABLISHED B'S REAL RATING FROM ITS DATASHEET:
+# a GoodWe GW5048D-ES, serial `55048ESU22AW0992`, 4600 W on the battery path
+# (goodwe/NOTES.md §1.1b). THIS FIXTURE DELIBERATELY DOES NOT USE IT. 3000 W is
+# kept because the only property these checks consume is that B's number is
+# UNMISTAKABLY not A's, and the real pair is 5000/4600 - a 400 W gap, narrower
+# than `slew_w` and inside the range where an off-by-one-unit bug and ordinary
+# control arithmetic produce indistinguishable numbers. Collapsing the fixture
+# onto the real values would cost these checks their separating power to buy
+# realism they do not use. So: ILLUSTRATIVE, NOT B'S RATING, and not a
+# placeholder for it either - the placeholder era ended on 2026-09-04.
 B_RATING_HYPOTHESIS = 3000.0
 
 
@@ -1384,13 +1393,29 @@ def _sign_site(hass, store=None, **over):
     return c
 
 
-async def _drive(c, n=14, dt=0.2, watch=None):
+async def _drive(c, n=14, dt=0.2, watch=None, pre=None):
+    """Drive `n` real cycles. `watch` samples AFTER each cycle, `pre` BEFORE it.
+
+    ⚠️ `pre` EXISTS BECAUSE `watch` ALONE CANNOT SEE WHAT A DETECTOR WAS HANDED,
+    AND SAFETY-39 IS HOW THAT WAS FOUND. `cycle()` evaluates the sign watchdogs
+    against THE STANDING COMMAND - the write from the PREVIOUS cycle - and then
+    issues a new one. So `watch`'s `last_write` is the command AFTER the
+    detector ran, and pairing it with `c.grid` builds a pair the detector never
+    saw. While `slew_w` was 1000 the loop was at its rail within two cycles and
+    consecutive commands were IDENTICAL, so the off-by-one was invisible; at a
+    rail-following slew the loop ramps and the two numbers differ by one step.
+    That is a fault in this harness, not in the code it grades - and a check
+    that compares an operator-facing sentence against the wrong cycle is
+    precisely the "the data could not reach the failure the text names" defect
+    MUTATION.md keeps finding. `pre` reads the operands the detector will use.
+    """
     seen = []
     for _ in range(n):
         await c.read_inputs()
+        before = {} if pre is None else pre(c)
         await c.cycle()
         if watch is not None:
-            seen.append(watch(c))
+            seen.append({**before, **watch(c)})
         await asyncio.sleep(dt)
     return seen
 
@@ -1499,6 +1524,50 @@ check("⚠️ AC 1. THE REVERSED UNIT TRIPS AND ITS SIBLING DOES NOT. The eviden
 check("...and the reason names the instrument, so the operator is sent to the "
       "right one", AGAINST_OWN_POWER in _b30.sign_wd.reason)
 print(f"       {_b30.sign_wd.reason!r}")
+# ⚠️ THE LAST CYCLE BEFORE B LATCHED, NAMED RATHER THAN INDEXED - part 5's
+# lesson and 9a's. After the trip B's share is 0 W and its measured power
+# follows it down, so a fixed index reads the REMEDY instead of the evidence.
+# Both operands are read off THIS OBSERVED CYCLE - `last_write` and `batt` off
+# the objects - and not off the fixture's constants, so the check cannot be
+# satisfied by two numbers the fixture happens to hold anyway (habit 2).
+_preb30 = [x for x in _s30 if not x["b"]]
+_midb30 = _preb30[-1]
+print(f"       last cycle before B latched: B stood "
+      f"{_midb30['stood'][1]:+.0f} W, B measured {_midb30['meas'][1]:+.0f} W")
+check("⚠️ ...AND THE ORDERED PAIR, on the ONE SIGN-DISAGREEMENT SENTENCE A "
+      "SHIPPED INSTALL CAN EVER PRINT. Part 9a pins the SITE banner's operand "
+      "order at main.py:1620; that call site is armed only at N>=2 and part 9c "
+      "asserts it is ABSENT at a roster of one, so on the shipped install the "
+      "PER-UNIT banner is the only one there is - and its call site is a "
+      "different line. Swapping the first two arguments at main.py:1560 - "
+      "`evaluate(stood, against, ...)` -> `evaluate(against, stood, ...)` - is "
+      "a ZERO-BYTE edit that changes NO trip decision, because `disagrees()` "
+      "is symmetric in those two arguments (`commanded_w * against_w < 0` with "
+      "an abs() gate on both). Nothing behavioural can see it and the full "
+      "21-file suite stayed green. What it changes is the SENTENCE: 'commanded "
+      "-1000 W against its own measured power +1000 W', the exact opposite of "
+      "which instrument read what, on the line somebody woken by this alarm "
+      "reads first - and it is persisted to `sign_reason` and re-read after a "
+      "restart. Graded on the CONTIGUOUS LITERAL with each value in its own "
+      "slot, per MUTATION.md habit 14: an `in` test on a number grades "
+      "PRESENCE, never ARRANGEMENT",
+      f"commanded {_midb30['stood'][1]:+.0f} W against its own measured power "
+      f"{_midb30['meas'][1]:+.0f} W" in _b30.sign_wd.reason)
+check("PRECONDITION for the line above, and without it that check is "
+      "decoration: the two operands are DIFFERENT NUMBERS and OPPOSITE IN "
+      "SIGN, so transposing them really does produce a different string. A "
+      "cycle where B's share and B's measured power were equal, or where "
+      "either was 0 W, would make the swapped sentence identical to the "
+      "correct one and the assertion could not reach the failure it names",
+      _midb30["stood"][1] != _midb30["meas"][1]
+      and _midb30["stood"][1] * _midb30["meas"][1] < 0
+      and f"{_midb30['stood'][1]:+.0f}" != f"{_midb30['meas'][1]:+.0f}")
+check("...and the SAME ordered pair is what an operator finds AFTER A RESTART, "
+      "because `sign_reason` is the persisted copy of this string. The swap "
+      "survives the container restart the same way the latch does",
+      f"commanded {_midb30['stood'][1]:+.0f} W against its own measured power "
+      f"{_midb30['meas'][1]:+.0f} W"
+      in str(_c30.store.data.get(unit_key("inverter-b", "sign_reason"), "")))
 # ⚠️ READ OFF THE ALLOCATION RECORD, NOT OFF `Controller.reason`. At a roster
 # of two `reason` is the SITE resolution's line - "loop -> 2000 W" - because
 # B's failsafe is a UNIT claim resolved on B's own actuator and never competes
@@ -1755,11 +1824,27 @@ async def _n1_sign():
         return _orig_eval(*a, **kw)
 
     c.site_sign_wd.evaluate = _spy
-    await _drive(c, n=12, dt=0.2)
-    return c, _n1_calls
+    # ⚠️ THE WATCH READS THE CONTROLLER'S OWN STATE, NOT `_spy`'s ARGUMENTS.
+    # `_n1_calls` records what was HANDED to a detector, so grading the banner
+    # against it would compare the swap against itself - the DEV-02 defect.
+    # `last_write` and `c.grid` are read off the objects the plant moved.
+    # ⚠️ `stood` COMES FROM `pre`, i.e. BEFORE `cycle()` RUNS (SAFETY-39). It is
+    # the STANDING command the sign watchdog is evaluated against; taking it
+    # after the cycle would pair this cycle's meter with next cycle's command
+    # and grade the banner against a pair that never existed. See `_drive`.
+    # `n` is 24 rather than 12 because at the shipped rail-following `slew_w`
+    # the loop needs nine cycles to reach a 2000 W rail instead of two.
+    seen = await _drive(c, n=24, dt=0.2, pre=lambda c: dict(
+        stood=(c.inverters[0].last_write
+               if c.inverters[0].last_write is not None
+               else c.inverters[0].target)),
+        watch=lambda c: dict(
+            grid=c.grid,
+            tripped=c.inverters[0].sign_wd.tripped))
+    return c, _n1_calls, seen
 
 
-_c1s, _n1_site_calls = asyncio.run(_n1_sign())
+_c1s, _n1_site_calls, _seen1s = asyncio.run(_n1_sign())
 _inv1 = _c1s.inverters[0]
 print(f"       roster={_c1s.units}  armed against {_inv1.sign_wd.against!r} "
       f"at {_inv1.sign_wd.cfg.min_w:.0f} W / {_inv1.sign_wd.cfg.hold_s:.0f} s")
@@ -1777,6 +1862,55 @@ check("...the reason sentence still says 'a meter reading', word for word - it "
       "is what an operator reads, what the action log carries and what is "
       "persisted, so it is graded on the literal",
       "against a meter reading" in _inv1.sign_wd.reason)
+# THE CYCLE THE LATCH HAPPENED ON, named rather than indexed: afterwards the
+# failsafe stands 0 W and the plant's meter relaxes, so a fixed index reads the
+# remedy. Both operands come off the controller, not off the fixture's options.
+#
+# ⚠️ IT IS THE FIRST *TRIPPED* SAMPLE, AND IT USED TO BE THE LAST UN-TRIPPED ONE
+# (SAFETY-39). The detector is evaluated INSIDE `cycle()` against the STANDING
+# command - the write from the previous cycle - and against the meter read at
+# the top of THIS one, and it latches on the cycle whose pair crosses the hold.
+# So the operands the sentence quotes belong to the LATCHING cycle, not to the
+# one before it. `stood` is now sampled by `_drive`'s `pre` hook, before
+# `cycle()` overwrites it with the failsafe's 0 W, which is what makes that
+# cycle readable at all - and it is why the old form had to reach back a cycle.
+# The two forms agreed while `slew_w` was 1000 and the loop sat at its rail with
+# consecutive commands IDENTICAL; at a rail-following slew the loop ramps and
+# they differ by exactly one step, which is how this was found.
+_first1s = [x for x in _seen1s if x["tripped"]]
+_mid1s = _first1s[0]
+print(f"       the cycle the latch happened on: stood {_mid1s['stood']:+.0f} W, "
+      f"meter {_mid1s['grid']:+.0f} W")
+print(f"       {_inv1.sign_wd.reason!r}")
+check("⚠️ ...AND THE ORDERED PAIR ON THE SHIPPING CALL SITE. This is the SAME "
+      "zero-byte defect part 9a closed at main.py:1620, one call site over at "
+      "main.py:1560 - and this is the one a one-inverter install actually "
+      "reaches, since the site detector is never armed here (asserted below). "
+      "`evaluate(stood, against, ...)` -> `evaluate(against, stood, ...)` "
+      "changes no trip decision - `disagrees()` is symmetric in those two "
+      "arguments - and inverts the banner to 'commanded +4000 W against a "
+      "meter reading -2000 W': the loop is standing at -2000 W of charge INTO "
+      "a +4000 W import and the latching banner says the opposite. The "
+      "substring check above passes under the swap, because both numbers are "
+      "still in the sentence; only the ORDERED PAIR can tell the slots apart "
+      "(MUTATION.md habit 14)",
+      f"commanded {_mid1s['stood']:+.0f} W against a meter reading "
+      f"{_mid1s['grid']:+.0f} W" in _inv1.sign_wd.reason)
+check("PRECONDITION: the two operands are DIFFERENT NUMBERS and OPPOSITE IN "
+      "SIGN on that cycle, so a transposition genuinely produces a different "
+      "string. Equal or zero operands would make the swapped banner identical "
+      "and the check above vacuous",
+      _mid1s["stood"] != _mid1s["grid"]
+      and _mid1s["stood"] * _mid1s["grid"] < 0
+      and f"{_mid1s['stood']:+.0f}" != f"{_mid1s['grid']:+.0f}")
+check("...and the persisted copy carries the same ordered pair, under BOTH the "
+      "namespaced key and the flat rollback mirror - which is what an operator "
+      "reads after the restart the latch is designed to survive",
+      f"commanded {_mid1s['stood']:+.0f} W against a meter reading "
+      f"{_mid1s['grid']:+.0f} W" in str(_c1s.store.data.get(REASON_KEY, ""))
+      and f"commanded {_mid1s['stood']:+.0f} W against a meter reading "
+      f"{_mid1s['grid']:+.0f} W"
+      in str(_c1s.store.data.get("sign_reason", "")))
 check("...the latch is under the same namespaced key with the same flat "
       "rollback mirror, and SAFETY-30's site pair is untouched at its default. "
       "A one-inverter install's state file is byte-identical to what it was",
@@ -1809,6 +1943,746 @@ check("...and no `sign_site` claim can be filed at a roster of one, so the "
       "arbitration is byte-identical to what shipped",
       "sign_site" not in _c1s.reason)
 
+
+print()
+print("8. SAFETY-32 ROUND 4's ENUMERATION: the two `any(...)` reductions over")
+print("   the roster whose only evidence is a latched NON-FIRST unit")
+# ⚠️ THIS SECTION IS NOT SAFETY-32's SUBJECT, AND IT IS HERE BECAUSE OF IT.
+# SAFETY-32 was rejected three times for the same shape one step over: a
+# reduction over roster length whose fixture could not separate it from a slice
+# of the roster. Round 4 therefore ENUMERATED every such reduction in
+# `Controller` - min, max, sum, any, all, sorted, [0], [-1] over
+# `self.inverters` / `self.packs` - and mutated each to `[:1]` to find out which
+# were GRADED. Two survived a green 19-file suite, both `any(i.sign_wd.tripped
+# for i in self.inverters)`, both SAFETY-30's, and this block is what closes
+# them. No shipped behaviour changes; the reductions were already right.
+#
+#   main.py `cycle()`, the stale-input hold  -  +4 bytes, 19/19 GREEN
+#   main.py `publish()`, the status vocabulary -  +4 bytes, 19/19 GREEN
+#
+# ⚠️ WHY THE SUITE COULD NOT SEE THEM, and it is the same sentence every time:
+# the only fixture that reached either was a roster of ONE, where
+# `self.inverters[:1]` IS `self.inverters`. Part 3 above builds a two-inverter
+# roster in which ONLY inverter B is latched - the exact data both reductions
+# needed - and neither of them was read on it. A fixture of N units cannot
+# separate reductions that agree on N units, one card over.
+#
+# ⚠️ AND BOTH ORDERS ARE RUN, for 12g's reason: a single "only B is latched"
+# fixture kills `[:1]` and leaves `[-1:]` - grade the roster by its LAST unit -
+# answering identically. The pair is what leaves no single-position slice.
+
+
+async def _latched_then_input_gap(reversed_idx):
+    """Latch ONE unit's sign watchdog, then take a SIBLING's reading away.
+
+    ⚠️ A REAL LATCH FROM A REAL EPISODE, not `sign_wd.tripped = True`: the same
+    `_SignHass` plant and the same `_drive()` part 3 uses, so the detector
+    reaches its verdict through the shipped path. Then one pack's SoC goes
+    missing for LESS than `stale_input_s`, which is the state the hold exists
+    for - a single missed poll must not become a fault.
+
+    THE FAULT THIS GRADES: a LATCHED unit must take the whole roster past that
+    hold, because the unit's `failsafe` SET is the thing parking it. Return
+    early and the unit's last share stays standing for the heartbeat to
+    re-emit - main.py's own comment: "the trip would stop acting the moment a
+    poll was missed". A reduction that looked at one roster POSITION would do
+    exactly that whenever the latched unit was not the position it looked at.
+    """
+    hass = _SignHass(load_w=2000.0, reversed_units={reversed_idx})
+    c = _sign_site(hass)
+    await _drive(c)
+    sibling = c.inverters[1 - reversed_idx]
+    sibling.soc = None
+    c.inputs_bad_since = datetime.now(timezone.utc)
+    await c.cycle()
+    return c
+
+
+_gap_b = asyncio.run(_latched_then_input_gap(1))
+_gap_a = asyncio.run(_latched_then_input_gap(0))
+for _tag, _c, _i in (("B latched", _gap_b, 1), ("A latched", _gap_a, 0)):
+    _pl = [p for p in (_c.allocation.plans if _c.allocation else ())
+           if p.unit == _c.inverters[_i].name]
+    print(f"       {_tag}, sibling's SoC missing 0 s: inputs_ok="
+          f"{_c.inputs_ok}, reason={_c.reason!r}, latched unit target="
+          f"{_c.inverters[_i].target}, why={_pl[0].why if _pl else '(no plan)'}")
+check("PRECONDITION (habit 1): on BOTH runs the site really is in the state "
+      "the hold is for - one pack's reading is missing, `inputs_ok` is False, "
+      "the gap is younger than `stale_input_s`, and the SITE latch is NOT "
+      "tripped, so the only thing that can carry the roster past the hold is "
+      "the per-unit `any()`. And exactly ONE unit is latched on each run, at "
+      "the OTHER position",
+      _gap_b.inputs_ok is False and _gap_a.inputs_ok is False
+      and _gap_b.site_sign_wd.tripped is False
+      and _gap_a.site_sign_wd.tripped is False
+      and [i.sign_wd.tripped for i in _gap_b.inverters] == [False, True]
+      and [i.sign_wd.tripped for i in _gap_a.inverters] == [True, False])
+check("⚠️ A LATCHED UNIT TAKES THE ROSTER PAST THE STALE-INPUT HOLD FROM EITHER "
+      "POSITION. Neither cycle parks on `inputs missing`; both go on to file "
+      "claims, and the latched unit is commanded 0 W by its OWN `failsafe` "
+      "claim, named in the allocation record. Grade this with "
+      "`self.inverters[:1]` and the B-latched run returns early - the +4-byte "
+      "mutation that was GREEN across all 19 files - and with "
+      "`self.inverters[-1:]` the A-latched run does. The remedy stops acting "
+      "the moment a poll is missed, which is main.py's own sentence for it",
+      not (_gap_b.reason or "").startswith("inputs missing")
+      and not (_gap_a.reason or "").startswith("inputs missing")
+      and _gap_b.inverters[1].target == 0.0
+      and _gap_a.inverters[0].target == 0.0
+      and all(any(p.unit == c.inverters[i].name and "failsafe" in p.why
+                  for p in (c.allocation.plans if c.allocation else ()))
+              for c, i in ((_gap_b, 1), (_gap_a, 0))))
+# ...and the counterfactual, which is what makes the two lines above a
+# DIFFERENCE rather than a description: with NOTHING latched, the very same
+# input gap DOES park the site on the hold. Without this the checks above would
+# be satisfied by a `cycle()` that never had a hold at all.
+async def _gap_no_latch():
+    c = _sign_site(_SignHass(load_w=2000.0))
+    await _drive(c, n=2)
+    c.inverters[0].soc = None
+    c.inputs_bad_since = datetime.now(timezone.utc)
+    await c.cycle()
+    return c
+
+
+_gap_none = asyncio.run(_gap_no_latch())
+print(f"       nothing latched, same gap: reason={_gap_none.reason!r}")
+check("...and the counterfactual (habit 7): with NO unit latched the SAME gap "
+      "DOES hold the site - `inputs missing 0s` - so the two runs above show "
+      "the latch carrying the roster past a hold that is really there, rather "
+      "than a hold that never fires",
+      (_gap_none.reason or "").startswith("inputs missing")
+      and not any(i.sign_wd.tripped for i in _gap_none.inverters))
+
+# --- and the SECOND survivor: the status vocabulary publish() hands the broker
+# ⚠️ THE EXISTING CHECK IS AT A ROSTER OF ONE, which is why this one exists.
+# "MQTT's controller-status sensor reports 'failsafe'" above drives a
+# single-inverter Controller, where `self.inverters[:1]` is the whole roster.
+# A site at 0 W reporting `running` is the failure main.py's comment names, and
+# at two inverters it is reachable whenever the latched unit is not the one a
+# narrowed reduction happens to read.
+_pub = {}
+
+
+def _published(ctl):
+    _pub.clear()
+    ctl.mqtt = type("P", (), {"enabled": True,
+                              "publish": lambda _s, v: _pub.update(v),
+                              "close": lambda _s: None})()
+    ctl.publish()
+    return dict(_pub)
+
+
+_pb, _pa = _published(_gap_b), _published(_gap_a)
+_pn = _published(_gap_none)
+print(f"       published status: B latched -> {_pb.get('status')!r}, "
+      f"A latched -> {_pa.get('status')!r}, none latched -> "
+      f"{_pn.get('status')!r}")
+check("⚠️ AND `publish()` SAYS `failsafe` WHICHEVER UNIT IS LATCHED. The status "
+      "sensor is the vocabulary every dashboard already reads, and a site with "
+      "one inverter parked by its own failsafe claim reporting `running` is "
+      "the exact failure main.py's comment names. `self.inverters[:1]` "
+      "publishes `running` on the B-latched site - +4 bytes, GREEN across all "
+      "19 files - and `self.inverters[-1:]` does it on the A-latched one",
+      _pb.get("status") == "failsafe" and _pa.get("status") == "failsafe")
+check("...and the counterfactual: the same two-inverter site with NOTHING "
+      "latched publishes `running`, so the two above are a difference the "
+      "reduction produced and not a constant",
+      _pn.get("status") == "running" and _gap_none.auto is True)
+
+# --- and the THIRD one the same enumeration found: the OPERATOR'S BANNER -----
+# ⚠️ `status_payload()`'s failsafe branch is a fourth `any(... for i in
+# self.inverters)`, and `self.inverters[:1]` there was +4 bytes and GREEN across
+# all 19 files too - for the third time, because the only fixture that reached
+# it was a roster of ONE. The banner is the ONE sentence at the top of the page;
+# a site holding an inverter at 0 W under a "Stopped" or "NOT READY" headline
+# sends the operator to the wrong question.
+_bn_b = _gap_b.status_payload()
+_bn_a = _gap_a.status_payload()
+_bn_n = _gap_none.status_payload()
+print(f"       banner: B latched -> {_bn_b['banner']!r}")
+print(f"               A latched -> {_bn_a['banner']!r}")
+print(f"               none      -> {_bn_n['banner']!r}")
+check("⚠️ AND THE BANNER LEADS WITH THE FAILSAFE WHICHEVER UNIT IS LATCHED, at "
+      "level `bad`, with the N>=2 sentence that names the unit's OWN measured "
+      "power rather than the meter. `self.inverters[:1]` drops the headline on "
+      "the B-latched site and `self.inverters[-1:]` on the A-latched one, and "
+      "the page then leads with whatever the next branch says",
+      _bn_b["level"] == _bn_a["level"] == "bad"
+      and _bn_b["banner"] == _bn_a["banner"]
+      and _bn_b["banner"].startswith("FAILSAFE")
+      and "its own measured power" in _bn_b["banner"])
+check("...and the counterfactual again: the same site with nothing latched "
+      "carries neither that level nor that sentence, so the banner really is "
+      "being produced by the reduction under test",
+      not _bn_n["banner"].startswith("FAILSAFE")
+      and _bn_n["banner"] != _bn_b["banner"])
+
+
+print()
+print("9. SAFETY-38: `site_standing` - the ONE quantity BOTH site guards are")
+print("   asked about - pinned by shares that CANNOT answer for it")
+# ⚠️ WHAT THIS SECTION PINS, AND WHY NOTHING ABOVE IT COULD.
+# `main.py`'s `site_standing = float(sum(standing.values()))` is the first
+# argument of SAFETY-30's site sign detector AND the `commanded_w` handed to
+# SAFETY-18's `looks_frozen()`. It was pinned by NOTHING. THREE mutations of it
+# were demonstrated live against a full green suite, and ALL THREE ARE COVERED
+# HERE:
+#
+#     sum(...) / max(1, len(standing))    the MEAN
+#     max(standing.values(), key=abs)     the LARGEST SHARE
+#     list(standing.values())[0]          the FIRST SHARE
+#
+# ⚠️ ROUND 1 OF THIS CARD SAID THE THIRD ONE WAS ALREADY CLOSED BY SAFETY-32's
+# PACKAGE-WIDE STRUCTURAL PIN AND TOLD FUTURE AUTHORS "DO NOT RE-COVER THAT ONE
+# HERE". THAT WAS FALSE, AND HOW IT BECAME FALSE IS THE USEFUL PART. It was
+# measured ONCE; that single run happened to hit test_peakguard.py's ~20%
+# CI-06 flake, the red was recorded as a mutation KILL, and the claim was then
+# written into four places. RE-MEASURED IN ROUND 2, on release/1.0 @ 86eaef2
+# carrying ONLY the `[0]` edit (+4 bytes, re-read from disk): the full suite is
+# 21/21 GREEN, and test_peakguard.py run FIVE times in isolation on that same
+# mutated tree is PASS PASS PASS PASS PASS. The mutation SURVIVES. (The
+# reviewer's own independent re-measurement of the same tree caught the flake
+# once - PASS PASS PASS FAIL PASS - which is the same verdict: a survivor, plus
+# a demonstration of the flake that produced the original error.) A SINGLE RED
+# FROM test_peakguard.py PROVES NOTHING - re-run it at least five times and NAME
+# the failing check before believing it. That rule is CI-06's, and this card is
+# the third measurement it has corrupted.
+#
+# THE MECHANISM, confirmed by reading 12j's own enumeration rather than by
+# argument. SAFETY-32's part 12j taints names BOUND to roster-carrying values
+# and lists ACCUMULATED in a loop over one. `standing` is neither: it is a dict
+# created empty at main.py:1554 and filled by SUBSCRIPT assignment
+# (`standing[inv.name] = stood`) inside the roster loop, and a subscript store
+# is not a binding 12j follows. So `standing` never enters its taint set at all,
+# and `sum(standing.values())` is not a roster site. Run 12j on a tree carrying
+# the `[0]` mutation and it enumerates main.py:1553, 1555 and 1690 - the three
+# `self.inverters` sites around this code - and NOT 1599. A structural pin
+# cannot see this line. Only the behavioural fixture below can.
+#
+# Identical shape, different meaning - which is precisely the blind spot
+# SAFETY-32 disclosed in its own words ("SEMANTICS. `min` -> `max` -> the mean
+# are edits invisible to any shape pin, permanently"). No shape pin will ever
+# close them. Only a behavioural fixture can, and this is it.
+#
+# ⚠️ WHY PART 5 ABOVE CANNOT SEE THEM, AND IT IS THIS REPOSITORY'S RECURRING
+# DEFECT INSIDE THE SITE HALF OF THE VERY CARD THAT NAMES IT. `_sign_site` is
+# the only N>=2 site fixture in the suite and it runs at
+# `site_sign_disagree_w: 320` with shares of about -2500 W EACH - every one of
+# them individually far OVER the gate. On values like those the sum, the mean
+# and the largest share all clear it, so all three reductions agree, and a
+# check whose two candidate answers happen to be EQUAL cannot observe a change
+# that swaps them. MUTATION.md habit 4. At a roster of ONE it is worse: there
+# `sum == mean == max == the one share` identically, so every mutation is
+# EQUIVALENT there - see 9c, where that identity is asserted rather than
+# assumed.
+#
+# ⚠️ SO THE NUMBERS BELOW ARE CHOSEN TO DISCRIMINATE, AND HERE IS THE
+# ARITHMETIC THEY ARE CHOSEN FOR. Two simulated units rated 220 W and 280 W
+# stand at their own rails, so `standing` is {-220, -280} in roster order:
+#
+#     sum                 -500 W   |500| > 300   OVER the gate   -> TRIPS
+#     mean                -250 W   |250| < 300   under it        -> silent
+#     max(..., key=abs)   -280 W   |280| < 300   under it        -> silent
+#     list(...)[0]        -220 W   |220| < 300   under it        -> silent
+#
+# FOUR DISTINCT MAGNITUDES - 500, 250, 280, 220 - of which exactly ONE clears
+# the SHIPPED 300 W gate. The asymmetry is load-bearing twice over: equal
+# shares would collapse mean, max and first onto one number and the fixture
+# could not tell them apart, and putting the SMALLER unit first is what keeps
+# `[0]` distinct from `max(key=abs)`.
+#
+# ⚠️ THE RATINGS ARE SIMULATED AND ARE NOT ANY REAL INVERTER'S. 220 W and 280 W
+# are chosen for the arithmetic in that table and for nothing else. In
+# particular they are NOT inverter B, which does not physically exist; B's
+# rating is 4600 W FROM ITS DATASHEET (goodwe/NOTES.md 1.1b) and no number in
+# this section is a measurement of anything.
+#
+# ⚠️ THE GATE IS THE SHIPPED ONE AND THE HOLD IS NOT. `site_sign_disagree_w` is
+# left at its default so this fixture is graded against the magnitude an
+# install actually runs; `site_sign_disagree_s` is shortened from 325 s to 2 s
+# because the hold is a wall clock and the campaign behind 325 s is measured on
+# the rig, not here. The gate is the coordinate this section is about.
+from app import peakguard as _pg38                                 # noqa: E402
+from app.freeze import rail_w as _rail_w38                         # noqa: E402
+from app.p1 import P1Sample as _P1Sample38                         # noqa: E402
+import time as _time38                                             # noqa: E402
+
+_S38_A_W, _S38_B_W = 220.0, 280.0     # SIMULATED. See the note above.
+_S38_LOAD_W = 2000.0
+_S38_FROZEN_METER_W = 2500.0
+
+
+def _s38_roster(*ratings):
+    """A CFG-04 `inverters:` roster, which is the shape an N>=2 install runs.
+
+    ⚠️ NOT `_sign_site`'s "build one from the flat keys and append a second".
+    `Controller.__init__` builds `Tuning` FROM the roster - `max_w=site_max_w` -
+    so a unit appended afterwards leaves the site loop bounded at ONE unit's
+    rating. That is harmless where part 3 uses it and fatal here: the whole
+    fixture is a site command standing at the ROSTER's rail.
+    """
+    return [{"name": name, "setpoint_entity": f"number.sp_{tag}",
+             "soc_entity": f"sensor.soc_{tag}", "batt_entity": f"sensor.batt_{tag}",
+             "max_w": w, "bms_soc_floor": 10}
+            for name, tag, w in zip(("inverter-a", "inverter-b", "inverter-c"),
+                                    ("a", "b", "c"), ratings)]
+
+
+class _S38Plant:
+    """Units that obey INSTANTLY and a meter that is `load - sum(measured)`.
+
+    The same modelling choice part 3 makes and for the same reason: an instant
+    plant removes the one mechanism that could make an obedient unit look
+    disobedient, so what remains to be graded is the ATTRIBUTION.
+    """
+
+    def __init__(self, load_w=_S38_LOAD_W):
+        self.load_w = float(load_w)
+        self.writes = []
+        self.calls = []
+        self.ctrl = None
+
+    async def call(self, domain, service, data):
+        self.calls.append((domain, service, data))
+
+    async def limits(self, entity):
+        return None
+
+    def measured(self):
+        if self.ctrl is None:
+            return []
+        return [float((i.last_write if i.last_write is not None else i.target) or 0.0)
+                for i in self.ctrl.inverters]
+
+    async def number(self, entity, invert=False):
+        m = self.measured()
+        if entity == "sensor.grid":
+            return self.load_w - sum(m)
+        for i, tag in enumerate(("a", "b", "c")):
+            if entity == f"sensor.soc_{tag}":
+                return 50.0
+            if entity == f"sensor.batt_{tag}":
+                return m[i] if i < len(m) else None
+        return None
+
+    async def set_number(self, entity, value):
+        self.writes.append((entity, float(value)))
+        return True
+
+
+def _s38_ctrl(hass, ratings, store=None, **over):
+    opts = {"meter_entity": "sensor.grid", "meter_source": "off",
+            "inverters": _s38_roster(*ratings),
+            "gain": -0.6,
+            # The per-unit pair, distinct from the site pair in BOTH
+            # coordinates, for part 3's reason: an equality below must be able
+            # to fail on the magnitude alone or on the hold alone.
+            "unit_sign_disagree_w": 250, "unit_sign_disagree_s": 1,
+            # ⚠️ `site_sign_disagree_w` DELIBERATELY ABSENT - the shipped 300 W
+            # default is the gate this whole section is graded against.
+            "site_sign_disagree_s": 2,
+            # SAFETY-31 is given a long window so the SITE is not stopped by
+            # circulation while this section grades the sign attribution. It is
+            # isolation, not a claim that SAFETY-31 is silent here.
+            "circulation_hold_s": 3600, "auto_start": True}
+    opts.update(over)
+    c = Controller(opts, hass, store if store is not None else _MemStore(),
+                   _P(), stop=asyncio.Event())
+    for inv in c.inverters:
+        inv.dev_min, inv.dev_max = -inv.max_w, inv.max_w
+    c.auto = True
+    hass.ctrl = c
+    return c
+
+
+def _s38_stood(c):
+    return [inv.last_write if inv.last_write is not None else inv.target
+            for inv in c.inverters]
+
+
+print()
+print("9a. the SITE sign detector: per-unit shares EACH BELOW the gate whose")
+print("    SUM clears it - the case the site detector exists for")
+
+
+async def _s38_site():
+    hass = _S38Plant()
+    c = _s38_ctrl(hass, (_S38_A_W, _S38_B_W))
+    seen = []
+    for _ in range(20):
+        await c.read_inputs()
+        await c.cycle()
+        seen.append(dict(grid=c.grid, stood=_s38_stood(c),
+                         meas=[i.batt for i in c.inverters],
+                         site=c.site_sign_wd.tripped,
+                         units=[i.sign_wd.tripped for i in c.inverters],
+                         following=c.following))
+        await asyncio.sleep(0.2)
+    return c, seen
+
+
+_c38, _s38seen = asyncio.run(_s38_site())
+# The last sample BEFORE the trip, named rather than indexed - part 5's lesson.
+# After the trip every command is 0 W, so a fixed index reads the REMEDY.
+_pre38 = [x for x in _s38seen if not x["site"]]
+_mid38 = _pre38[-1]
+_GATE38 = _c38.site_sign_wd.cfg.min_w
+_share38 = list(_mid38["stood"])
+_red38 = {"sum": sum(_share38),
+          "mean": sum(_share38) / max(1, len(_share38)),
+          "max(key=abs)": max(_share38, key=abs),
+          "[0]": _share38[0]}
+print(f"       last cycle before the trip: stood "
+      f"{[round(x) for x in _share38]}  measured "
+      f"{[round(x) for x in _mid38['meas']]}  meter {_mid38['grid']:+.0f} W")
+print(f"       site gate {_GATE38:.0f} W (SHIPPED default), hold "
+      f"{_c38.site_sign_wd.cfg.hold_s:.0f} s")
+for _k, _v in _red38.items():
+    print(f"         {_k:>13} = {_v:+7.1f} W   "
+          f"{'OVER' if abs(_v) > _GATE38 else 'under'} the gate")
+check("PRECONDITION: the gate really is the SHIPPED 300 W, so this fixture is "
+      "graded against the magnitude an install runs and not against a number "
+      "chosen to make it pass",
+      _GATE38 == float(SIGN_OPTION_DEFAULTS["site_sign_disagree_w"]) == 300.0)
+check("⚠️ PRECONDITION, AND IT IS THE WHOLE OF SAFETY-38. EVERY per-unit share "
+      "is BELOW the site gate and their SUM is OVER it. `_sign_site` above "
+      "cannot make this statement - its shares are each individually over the "
+      "gate, so sum, mean and largest-share all agree there and its values "
+      "cannot observe a change that swaps them",
+      len(_share38) >= 2
+      and all(abs(s) < _GATE38 for s in _share38)
+      and abs(sum(_share38)) > _GATE38)
+check("...and the FOUR candidate reductions give FOUR DISTINCT answers on it, "
+      "of which exactly ONE clears the gate. That is what makes this fixture "
+      "able to tell `sum` from the mean, from the largest share and from the "
+      "first share - and it is the property the existing site fixture lacks",
+      len({round(v, 6) for v in _red38.values()}) == 4
+      and [k for k, v in _red38.items() if abs(v) > _GATE38] == ["sum"])
+check("PRECONDITION: EVERY inverter is obeying - each unit's measured power "
+      "agrees in sign with its own share - and the site is charging into an "
+      "importing house. Without this the trip below could be a per-unit fault "
+      "in disguise rather than the site fault this grades",
+      all(s * m > 0 for s, m in zip(_mid38["stood"], _mid38["meas"]))
+      and sum(_mid38["stood"]) * _mid38["grid"] < 0
+      and _mid38["following"] is True)
+check("⚠️ THE SITE WATCHDOG TRIPS ON THE SUM, and no per-unit watchdog does. "
+      "Under ALL THREE semantic mutations - `sum -> mean`, "
+      "`sum -> max(key=abs)` AND `sum -> list(...)[0]` - NOTHING trips, ever: "
+      "the reviewer's tree was still commanding -500 W of charge into a "
+      "+2500 W import at t = 595 s with following=True. This is the check all "
+      "three go red on. `[0]` is here BECAUSE IT IS NOT COVERED ELSEWHERE - "
+      "see the section header for the mis-measurement that said it was",
+      _c38.site_sign_wd.tripped
+      and not any(i.sign_wd.tripped for i in _c38.inverters))
+print(f"       {_c38.site_sign_wd.reason!r}")
+check("⚠️ ...and the sentence an operator reads carries THE SUM IN THE "
+      "COMMANDED SLOT AND THE METER IN THE METER SLOT - the ORDERED PAIR, not "
+      "two numbers loose in a sentence. ROUND 1 ASSERTED `f'{sum(...):.0f} W' "
+      "in reason`, i.e. that '-500 W' appears SOMEWHERE, AND THAT WAS A HOLE "
+      "ONE LINE WIDE. Swapping the detector's first two arguments - "
+      "`evaluate(site_standing, self.grid, ...)` -> "
+      "`evaluate(self.grid, site_standing, ...)`, a ZERO-BYTE edit at "
+      "main.py:1620 - leaves BOTH numbers in the string and moves each into "
+      "the other's slot, so the substring test still passed and the whole "
+      "suite stayed green. The swapped banner reads 'commanded +2500 W "
+      "against a meter reading -500 W': the site is standing at -500 W of "
+      "charge INTO a +2500 W import and the latching, site-stopping banner "
+      "tells the operator the exact opposite, on the one line somebody woken "
+      "by this alarm reads first. watchdog.py:658-665 calls naming the wrong "
+      "instrument there 'a false statement about which instrument produced "
+      "the evidence'. A check whose data cannot reach the failure it names is "
+      "MUTATION.md's own defect; this is the line that closes it",
+      f"commanded {sum(_share38):+.0f} W against a meter reading "
+      f"{_mid38['grid']:+.0f} W" in _c38.site_sign_wd.reason)
+check("...and it stops the WHOLE site, through the `sign_site` claim by name "
+      "rather than by some other guard happening to stop it",
+      _c38.target == 0.0 and "sign_site" in _c38.reason
+      and all(i.target == 0.0 for i in _c38.inverters)
+      and _c38.store.data.get("site_sign_tripped") is True)
+# ⚠️ THE COUNTERFACTUAL, and it is what says the check above is produced by the
+# SUM crossing the gate rather than by two inverters being present. Same plant,
+# same roster shape, same everything - except the units are rated so that the
+# sum lands UNDER the gate. Nothing may trip.
+_S38_SMALL = (120.0, 130.0)          # sum 250 W: under the 300 W gate
+
+
+async def _s38_under():
+    hass = _S38Plant()
+    c = _s38_ctrl(hass, _S38_SMALL)
+    for _ in range(20):
+        await c.read_inputs()
+        await c.cycle()
+        await asyncio.sleep(0.2)
+    return c
+
+
+_c38u = asyncio.run(_s38_under())
+print(f"       counterfactual: stood {[round(x) for x in _s38_stood(_c38u)]}  "
+      f"sum {sum(_s38_stood(_c38u)):+.0f} W  meter {_c38u.grid:+.0f} W")
+check("...and the counterfactual: the SAME inverted-gain site whose shares sum "
+      "to 250 W - under the gate - does NOT trip, over the same 20 cycles. So "
+      "the trip above is the sum crossing 300 W and not the mere presence of a "
+      "second inverter",
+      abs(sum(_s38_stood(_c38u))) < _GATE38
+      and not _c38u.site_sign_wd.tripped
+      and not any(i.sign_wd.tripped for i in _c38u.inverters))
+# ⚠️ AND A SECOND COUNTERFACTUAL, WHICH EXISTS BECAUSE OF A MUTATION THE CHECKS
+# ABOVE COULD NOT SEE AND THIS SEARCH WENT LOOKING FOR.
+# `site_standing = float(self.target)` - the arbiter's SITE TARGET instead of
+# the sum of what actually stands on the wire - is -11 bytes, and it survived
+# every check above AND the whole 20-file suite, because in every fixture so
+# far the two are the same number. THEY ARE NOT THE SAME NUMBER when a setpoint
+# device's own reported range is narrower than its `max_w`: the `device`
+# P_SAFETY claim is filed PER ACTUATOR (main.py, `actuator_of("device", inv)`),
+# so it bounds each unit's SHARE and never the site target, and
+# `clamp_to_rating()` clips again on the way out. Here the site asks for -500 W
+# and -250 W stands.
+#
+# WHICH ONE THE GUARDS MEAN IS ALREADY WRITTEN DOWN, IN BOTH OF THEM: SAFETY-02
+# grades "the command standing on the wire", and `looks_frozen()`'s docstring
+# says `commanded_w` is "the EMITTED setpoint - what the arbiter resolved and
+# `write_setpoint()` put on the wire - not the loop's raw wish". SAFETY-20 is
+# the whole card about the difference. This check is those sentences made to
+# bite: on the site target the detector fires on a site that is standing at
+# -250 W against a +2250 W meter - under its own 300 W gate - which is a
+# LATCHING, site-stopping false trip on an install whose inverters simply
+# report a narrower range than the operator typed.
+_S38_DEV = (120.0, 130.0)          # narrower than the 220/280 W ratings
+
+
+async def _s38_devclamped():
+    hass = _S38Plant()
+    c = _s38_ctrl(hass, (_S38_A_W, _S38_B_W))
+    for inv, d in zip(c.inverters, _S38_DEV):
+        inv.dev_min, inv.dev_max = -d, d
+    for _ in range(20):
+        await c.read_inputs()
+        await c.cycle()
+        await asyncio.sleep(0.2)
+    return c
+
+
+_c38d = asyncio.run(_s38_devclamped())
+_stood38d = _s38_stood(_c38d)
+print(f"       device-clamped: site target {_c38d.target:+.0f} W but only "
+      f"{[round(x) for x in _stood38d]} = {sum(_stood38d):+.0f} W stands, "
+      f"meter {_c38d.grid:+.0f} W")
+check("PRECONDITION: the site TARGET and the EMITTED total are DIFFERENT "
+      "numbers here, on opposite sides of the gate - -500 W asked, -250 W "
+      "standing. Without that separation this check and the one above compare "
+      "two values that happen to be equal, which is the defect this card is "
+      "the sixth instance of",
+      abs(_c38d.target) > _GATE38 and abs(sum(_stood38d)) < _GATE38)
+check("⚠️ ...and NOTHING TRIPS, because the quantity graded is what STANDS ON "
+      "THE WIRE and not what the arbiter asked for. `float(self.target)` is "
+      "-11 bytes, survives the other 20 files, and turns this ordinary "
+      "narrow-rating install into a latching site-wide false trip",
+      not _c38d.site_sign_wd.tripped
+      and not any(i.sign_wd.tripped for i in _c38d.inverters)
+      and _c38d.target != 0.0)
+
+
+print()
+print("9b. THE SECOND CONSUMER: the same value is SAFETY-18's `commanded_w`")
+print("    inside `looks_frozen()`, and both mutations blind it too")
+# ⚠️ THIS IS THE AC THE CARD REFUSES TO LET BE SCOPED OUT SILENTLY.
+# `site_standing` is handed to `looks_frozen()` at main.py's `peakguard.decide(
+# ..., frozen=...)` call, where it is the EMITTED command graded against the
+# site rail. Both surviving mutations shrink it there too, and nothing went red.
+#
+# THE RAIL ARITHMETIC, and it is the same discrimination as 9a at a different
+# threshold: the site rail is `RAIL_FRAC * site_max_w` = 0.95 * 500 = 475 W.
+#
+#     sum                 500 W   >= 475   RAILED  -> BLIND_FROZEN, floor 0 W
+#     mean                250 W   <  475   silent
+#     max(..., key=abs)   280 W   <  475   silent
+#     list(...)[0]        220 W   <  475   silent
+#
+# ⚠️ THE SIGN IS FLIPPED FROM 9a ON PURPOSE. Here the gain is the SHIPPED
+# POSITIVE one and the frozen meter reads IMPORT, so the site discharges +500 W
+# against a +2500 W import - the two agree in sign, SAFETY-30 has nothing to
+# say, and this section grades SAFETY-18 alone. Reusing 9a's inverted gain
+# would have the site sign latch park everything at 0 W and the freeze
+# conjunction could then never be true: a check measuring the other guard's
+# remedy.
+#
+# WHAT THE MUTATIONS COST HERE, measured rather than asserted: on the shipped
+# tree the guard goes blind and files `floor_w = 0.0` - "the battery may not
+# import while the billed quarter cannot be measured". Under both mutations it
+# is NOT BLIND AT ALL and files `floor_w = None`, so the site may go on
+# charging through a quarter whose billed average is unobservable. That is the
+# capacity-tariff hazard SAFETY-18 exists for, silently disarmed.
+
+
+class _S38Src:
+    """The transport's own `unchanged_s`, which only homewizard_local has."""
+
+    def __init__(self, unchanged_s):
+        self.unchanged_s = float(unchanged_s)
+
+
+def _s38_feed(c, w, ts=None, mono=None):
+    now = ts if ts is not None else datetime.now(timezone.utc)
+    c.p1.submit(_P1Sample38(
+        ingest_ts=now,
+        ingest_mono=mono if mono is not None else _time38.monotonic(),
+        telegram_ts=now, source="homewizard_local",
+        import_w=max(w, 0.0), export_w=max(-w, 0.0), net_w=w,
+        per_phase_w=(w,), per_phase_import_w=(max(w, 0.0),)))
+
+
+def _s38_seed_quarter(c, w):
+    """Backfill the OPEN quarter with the same stuck value, at 10 s spacing.
+
+    ⚠️ THIS IS NOT DECORATION. Without it the open block is mostly uncovered and
+    `blindness()` answers BLIND_COVERAGE - which is still blind, still floor
+    0 W, and would therefore MASK the mutations: the mutant would reach the
+    same action by a different route and a check on the action alone could not
+    see the difference it names. Seeded, the mutant is not blind at ALL, which
+    is the honest measurement of what the mutation costs. A meter that has been
+    stuck at the same reading all quarter is also what SAFETY-18 is about.
+    """
+    wall = _time38.time()
+    q0 = (int(wall) // 900) * 900
+    mono0 = _time38.monotonic() - (wall - q0)
+    t = float(q0)
+    while t < wall:
+        _s38_feed(c, w, datetime.fromtimestamp(t, timezone.utc), mono0 + (t - q0))
+        t += 10.0
+
+
+def _s38_frozen_ctrl(hass, ratings, unchanged_s=600.0, gain=0.05):
+    # ⚠️ `gain` 0.05 IS THE SCHEMA FLOOR AND IT IS HERE TO BUY A RAMP. At the
+    # shipped 0.6 the loop is at the rail on cycle 0 and the fixture has no
+    # BELOW-the-rail cycles to use as its counterfactual. At 0.05 the site
+    # climbs 125 W a cycle and crosses 475 W part way through the run, so the
+    # SAME run carries both answers.
+    c = _s38_ctrl(hass, ratings, meter_source="homewizard_local",
+                  p1_host="meter.local", gain=gain)
+    c.p1_source = _S38Src(unchanged_s)
+    return c
+
+
+# ⚠️ `n` IS 20 AND WAS 8 (SAFETY-39). The comment on `_s38_frozen_ctrl` says
+# gain 0.05 is there "to buy a ramp" so that the SAME run carries both a
+# below-the-rail and an at-the-rail answer. At the shipped rail-following
+# `slew_w` the ramp is now the SLEW - 55 W a cycle against this 500 W site,
+# where gain 0.05 alone gave 125 - so eight cycles no longer reach the rail and
+# the run carried only the counterfactual. The fixture needs the cycles, not a
+# different tuning: the point is a run that crosses the rail part way through.
+async def _s38_frozen(ratings, meter_w=_S38_FROZEN_METER_W, n=20):
+    hass = _S38Plant()
+    c = _s38_frozen_ctrl(hass, ratings)
+    _s38_seed_quarter(c, meter_w)
+    seen = []
+    for _ in range(n):
+        _s38_feed(c, meter_w)
+        await c.read_inputs()
+        await c.cycle()
+        pg = c.peak_guard
+        seen.append(dict(stood=_s38_stood(c),
+                         blind=None if pg is None else pg.blind,
+                         floor=None if pg is None else pg.floor_w))
+        await asyncio.sleep(0.05)
+    return c, seen
+
+
+_c38f, _s38f = asyncio.run(_s38_frozen((_S38_A_W, _S38_B_W)))
+_RAIL38 = _rail_w38(_c38f.site_max_w,
+                    dev_min=_c38f.site_dev_bound("dev_min"),
+                    dev_max=_c38f.site_dev_bound("dev_max"))
+_last38 = _s38f[-1]
+_below38 = [x for x in _s38f if abs(sum(x["stood"])) < _RAIL38]
+print(f"       site rail {_RAIL38:.0f} W of site_max_w {_c38f.site_max_w:.0f} W; "
+      f"meter stuck at {_S38_FROZEN_METER_W:+.0f} W for "
+      f"{_c38f.p1_source.unchanged_s:.0f} s (freeze hold "
+      f"{_c38f.freeze_wd.cfg.hold_s:.0f} s)")
+for _x in _s38f:
+    print("         stood %-16s sum %+7.1f W   floor=%s   blind=%r"
+          % ([round(v) for v in _x["stood"]], sum(_x["stood"]),
+             _x["floor"], _x["blind"]))
+check("PRECONDITION: at the rail EVERY per-unit share is BELOW the site rail "
+      "and their SUM is at or over it - the same discrimination as 9a, at "
+      "SAFETY-18's threshold instead of SAFETY-30's. `[0]`, the mean and the "
+      "largest share are 220, 250 and 280 W against a 475 W rail",
+      len(_last38["stood"]) >= 2
+      and all(abs(s) < _RAIL38 for s in _last38["stood"])
+      and abs(sum(_last38["stood"])) >= _RAIL38
+      and len({round(v, 6) for v in
+               (sum(_last38["stood"]),
+                sum(_last38["stood"]) / len(_last38["stood"]),
+                max(_last38["stood"], key=abs),
+                _last38["stood"][0])}) == 4)
+check("⚠️ THE PEAK GUARD GOES BLIND ON SAFETY-18's CONJUNCTION and forbids "
+      "charging - floor 0 W - because the SITE's total command is at the rail "
+      "while the meter has stopped moving. Under `sum -> mean` and "
+      "`sum -> max(key=abs)` it is not blind at all and files no floor, so the "
+      "battery may keep importing through an unmeasurable billed quarter. This "
+      "is the second consumer, and it is covered rather than scoped out",
+      _last38["blind"] == _pg38.BLIND_FROZEN and _last38["floor"] == 0.0)
+check("...and the counterfactual, from the SAME run: on the earlier cycles the "
+      "site command had not yet reached the rail, and the guard did NOT report "
+      "SAFETY-18 - with the meter equally frozen the whole time. So the "
+      "verdict is produced by the COMMAND MAGNITUDE `site_standing` carries, "
+      "not by `unchanged_s` alone",
+      len(_below38) >= 2
+      and all(x["blind"] != _pg38.BLIND_FROZEN for x in _below38))
+
+
+print()
+print("9c. AT ONE INVERTER NOTHING CHANGES, and 'nothing' is asserted")
+# ⚠️ THE REASON THIS SUBSECTION EXISTS. At a roster of one `standing` has a
+# single entry, so `sum`, the mean, `max(key=abs)` and `[0]` are THE SAME
+# NUMBER: all three mutations are genuinely EQUIVALENT there and no fixture at
+# N=1 can ever separate them. That is a fact about the arithmetic, and leaving
+# it implicit is how "the shipped install is covered" gets believed. It is
+# asserted here, on a real one-inverter controller's own standing command, so
+# the claim rests on the roster rather than on the reader.
+_S38_ONE = (500.0,)
+
+
+async def _s38_one():
+    hass = _S38Plant()
+    c = _s38_frozen_ctrl(hass, _S38_ONE)
+    _s38_seed_quarter(c, _S38_FROZEN_METER_W)
+    for _ in range(20):          # SAFETY-39: the slew is the ramp now - see _s38_frozen
+        _s38_feed(c, _S38_FROZEN_METER_W)
+        await c.read_inputs()
+        await c.cycle()
+        await asyncio.sleep(0.05)
+    return c
+
+
+_c38one = asyncio.run(_s38_one())
+_one38 = _s38_stood(_c38one)
+_onered38 = (sum(_one38), sum(_one38) / max(1, len(_one38)),
+             max(_one38, key=abs), _one38[0])
+print(f"       roster of {len(_c38one.inverters)}: stood "
+      f"{[round(v) for v in _one38]}  -> sum/mean/max/first = "
+      f"{tuple(round(v, 1) for v in _onered38)}")
+check("at a roster of ONE the four reductions are ONE NUMBER - so all three "
+      "mutations of `site_standing` are EQUIVALENT on a shipped install and no "
+      "N=1 fixture could ever tell them apart. That is why this card needed a "
+      "roster of two, stated as an assertion rather than left to the reader",
+      len(_c38one.inverters) == 1
+      and len({round(v, 6) for v in _onered38}) == 1)
+check("...and the one-inverter site still reaches SAFETY-18's verdict on that "
+      "same number, unchanged: the command is at the rail, the meter has "
+      "stopped moving, the guard is blind and forbids charging",
+      _c38one.peak_guard is not None
+      and _c38one.peak_guard.blind == _pg38.BLIND_FROZEN
+      and _c38one.peak_guard.floor_w == 0.0
+      and abs(sum(_one38)) >= _rail_w38(
+          _c38one.site_max_w,
+          dev_min=_c38one.site_dev_bound("dev_min"),
+          dev_max=_c38one.site_dev_bound("dev_max")))
+check("...and the SITE sign detector is still absent at a roster of one - part "
+      "7 counts the calls; this only records that a fixture built the other "
+      "way round, from an `inverters:` roster, reaches the same state",
+      not _c38one.site_sign_wd.tripped
+      and _c38one.site_sign_wd.disagree_since is None)
+
 print()
 if fails:
     print(f"{len(fails)} FAILED: {', '.join(fails)}")

goodwe_controller/tools/slew_sim.py

@@ -0,0 +1,339 @@
+#!/usr/bin/env python3
+"""SAFETY-39's evidence, on admin/goodwe's OWN plant model.
+
+    python3 tools/slew_sim.py --repro     # ⭐ the 2026-09-05 excursion, replayed
+    python3 tools/slew_sim.py --slew      # the derivation: slew against the rail
+    python3 tools/slew_sim.py --gain      # what the slew does NOT own
+    python3 tools/slew_sim.py --roster    # N=1 -> N=2, and the rail that moved
+    python3 tools/slew_sim.py --all
+
+WHY THIS IS A SCRIPT AND NOT A `test_*.py`
+==========================================
+Byte for byte tools/alloc_sim.py's reason, and it has not changed: this needs
+admin/goodwe checked out beside this repository for `plantsim.Plant`, and the
+add-on's CI job has no credentials for that repository - it is private and the
+job's token is minted for this one. A `test_*.py` here is globbed and RUN by
+.gitea/workflows/checks.yml, so a file that needs the sibling repo would either
+fail the gate or - worse - pass SILENTLY having checked nothing.
+
+So the rig evidence lives here and is quoted in the pull request and in
+DECISIONS/SAFETY-39-slew-against-the-rail.md, and test_control.py's SAFETY-39
+section grades the same properties in CI against a plant it models itself and
+says it models. The two plants are INDEPENDENT - a first-order lag written in
+test_control.py versus `plantsim.Plant`'s ramp-plus-lag with an efficiency and
+a SoC integrator - and they agree on every sign and rank below, which is worth
+more than either alone.
+
+WHAT IS REAL IN HERE
+====================
+  * the control law - `compute()` and `Tuning`, imported out of THIS checkout,
+    never transcribed.
+  * the wire - every command goes out through `frame_check.setpoint_atomic()`,
+    the firmware's own encoder, and back in through `plantsim.parse`/`decode`,
+    because `Inverter.command()` is what drives the modelled unit.
+  * the plant - `plantsim.Plant`, the model the rig uses.
+
+MODELLED, and therefore not evidence about the thing modelled:
+  * the meter. `grid = load - pv - sum(battery)` with no poll delay and no
+    noise, sampled once per tick. The real P1 is a poll with its own age.
+  * the tick. 2.0 s, which is what the live install was MEASURED running on
+    2026-09-05; it is a parameter here (`--tick`) and not a constant, because
+    the whole of this card is that the derivation depends on the regime.
+
+⚠️ WHAT THIS CANNOT SHOW, SAID BEFORE THE RESULTS RATHER THAN AFTER THEM
+=======================================================================
+THE -5154 W BATTERY EXCURSION IS NOT REPRODUCIBLE HERE, AND NOT BECAUSE THE
+TUNING IS WRONG. `plantsim.Plant.limit()` clamps the plant at `p_max`, so the
+modelled battery cannot exceed its rating by one watt at any tuning, on any
+step, ever. Neither can test_control.py's model. An acceptance criterion of
+"battery power no longer exceeds max_w in simulation" would therefore be
+UNFALSIFIABLE - it passes on the broken configuration too - so no criterion in
+this card is written on it, and the ticket's own AC to that effect is the one
+that had to be rewritten rather than met.
+
+What IS reproducible, and is what everything below measures:
+  * the setpoint stepping a full `slew_w` per tick, over and over (the live
+    symptom that escalated 2 -> 1 -> 13 -> 43 large steps per 30 min);
+  * the loop OVER-ABSORBING - taking more than the site needed - and driving
+    the meter from EXPORT into IMPORT, i.e. manufacturing the error it chases.
+
+⚠️ INVERTER B DOES NOT EXIST. `plantsim.INVERTER_B` is inverter A's numbers
+COPIED, `measured=False`. Every N=2 row below is therefore a result about TWO
+COPIES OF A on a 10000 W rail, NOT about the ~9600 W site that B's datasheet
+and serial imply (goodwe/NOTES.md §1.1b; B is a GW5048D-ES rated 4600 W, and
+that figure may itself be DC). Each such row prints the caveat with it.
+"""
+import argparse
+import math
+import os
+import pathlib
+import sys
+
+HERE = pathlib.Path(__file__).resolve().parent
+ADDON = HERE.parent.parent            # the goodwe-addon checkout root
+
+
+def find_sim():
+    """admin/goodwe's `sim/` directory, or None - and the caller says which.
+
+    $GOODWE_SIM first, the same override test_freeze.py and alloc_sim.py take,
+    then the sibling checkouts that actually occur. A missing sibling is not a
+    finding about the control law and must never be reported as one.
+    """
+    cands = []
+    if os.environ.get("GOODWE_SIM"):
+        cands.append(pathlib.Path(os.environ["GOODWE_SIM"]))
+    for up in (ADDON.parent, ADDON.parent.parent):
+        cands += [up / "goodwe" / "sim", up / "goodwe-session" / "goodwe" / "sim"]
+    for c in cands:
+        if (c / "plantsim.py").exists():
+            return c
+    return None
+
+
+def load(sim):
+    sys.path[:0] = [str(sim), str(sim.parent / "master")]
+    os.environ.setdefault("GOODWE_ADDON_REPO", str(ADDON))
+    sys.path[:0] = [str(ADDON / "goodwe_controller")]
+    import plantsim                                          # noqa: E402
+    from app import control                                  # noqa: E402
+    return plantsim, control
+
+
+# ---------------------------------------------------------------------------
+# one experiment
+
+
+def step_run(plantsim, control, *, gain, slew_w, rail_w, n=1, tick_s=2.0,
+             export_w=3385.0, load_w=350.0, phase=5, cycles=300, dt=0.05,
+             lag_s=None):
+    """One export step onto a converged loop, through the real wire.
+
+    `rail_w` is the SITE rail - what `main.py` hands `compute()` as `max_w`
+    (`Controller.site_max_w`, the roster sum). Each of the `n` modelled units
+    is rated `rail_w / n` and is commanded its even share, which is the
+    arrangement ARCH-01's split-invariance says any valid split is equivalent
+    to at the meter.
+    """
+    over = {} if lag_s is None else dict(lag_s=lag_s)
+    spec = dict(plantsim.INVERTER_A, rating_w=rail_w / n, **over)
+    invs = [plantsim.Inverter.from_spec(name, spec) for name in "AB"[:n]]
+    site = plantsim.Site(invs, load=load_w, pv=0.0)
+    tuning = control.Tuning(gain=gain, max_w=rail_w, slew_w=slew_w,
+                            target_grid_w=-10.0)
+    prev, i_w, sat = 0.0, None, 0
+    worst_import, peak, biggest, last = -1e9, 0.0, 0.0, None
+    for c in range(cycles):
+        if c == phase:
+            site.pv = export_w + load_w
+            site.grid = site.load - site.pv - site.battery
+        # ⚠️ ONE UNIT'S POWER, NOT THE SITE'S SUM, at n > 1. The shipped add-on
+        # binds a single `inverter_power` sensor, so a two-inverter install has
+        # a loop that sees unit A only. sitesim.run_site() makes the same choice
+        # and says at length why feeding the sum would be a KINDER rig than the
+        # deployment.
+        actual = invs[0].plant.actual
+        d = control.compute(prev, site.grid, actual, tuning, sat, i_w)
+        if c >= phase and last is not None:
+            biggest = max(biggest, abs(d.target_w - last))
+        last = d.target_w
+        prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+        for inv in invs:
+            inv.command(d.target_w / n)
+        site.settle(tick_s, dt=dt)
+        if c >= phase:
+            worst_import = max(worst_import, site.grid)
+            peak = max(peak, abs(site.battery))
+    return dict(imp=worst_import, over=peak - export_w, step=biggest)
+
+
+def family(plantsim, control, *, exports=None, phases=(5, 6, 7), **kw):
+    """The worst case over a family of step sizes and phases.
+
+    ⚠️ A FAMILY, NOT ONE STEP, AND THAT IS ITSELF A FINDING. A single run of
+    this loop is not evidence: the 15 W deadband, the 10 W quantisation and the
+    phase of the step against the tick move the answer by hundreds of watts,
+    NON-MONOTONICALLY, so two adjacent slews rank either way depending on which
+    step you happen to run. The first version of this derivation was a single
+    step and reported gain 0.3 as WORSE than gain 0.6, which the family shows is
+    backwards. Everything printed below is a worst case over the family, which
+    is how admin/goodwe grades the same kind of quantity (config.yaml's "1890
+    closed-loop runs", "924 runs").
+    """
+    exports = exports or range(1000, 4300, 200)
+    worst = dict(imp=-1e9, over=-1e9, step=0.0, big=0, runs=0)
+    for export_w in exports:
+        for phase in phases:
+            r = step_run(plantsim, control, export_w=float(export_w),
+                         phase=phase, **kw)
+            worst["runs"] += 1
+            worst["imp"] = max(worst["imp"], r["imp"])
+            worst["over"] = max(worst["over"], r["over"])
+            worst["step"] = max(worst["step"], r["step"])
+            worst["big"] += r["step"] >= 900.0
+    return worst
+
+
+def row(label, w):
+    print(f"  {label:<44} step {w['step']:6.0f} W   "
+          f"{w['big']:3}/{w['runs']} runs >= 900 W   "
+          f"over-absorbed {w['over']:6.0f} W   meter to {w['imp']:+7.0f} W")
+
+
+# ---------------------------------------------------------------------------
+
+
+def repro(ps, ct, tick_s):
+    print("⭐ THE 2026-09-05 EXCURSION, REPLAYED - gain 0.6, max_w 5000, "
+          f"slew_w 1000, {tick_s:.0f} s tick")
+    print("   Live, 11:43:55-11:45:55: grid -3385 W, setpoint 380 -> 5000 in five")
+    print("   ticks, battery -5154 W, grid +2831 W. One 3385 W export step here:\n")
+    print(f"   {'t':>5} {'grid in':>9} {'setpoint':>9} {'battery':>9} {'grid out':>9}  reason")
+    spec = dict(ps.INVERTER_A)
+    inv = ps.Inverter.from_spec("A", spec)
+    site = ps.Site([inv], load=350.0, pv=0.0)
+    t = ct.Tuning(gain=0.6, max_w=5000.0, slew_w=1000.0, target_grid_w=-10.0)
+    prev, i_w, sat = 0.0, None, 0
+    for c in range(34):
+        if c == 5:
+            site.pv = 3385.0 + 350.0
+            site.grid = site.load - site.pv - site.battery
+        g = site.grid
+        d = ct.compute(prev, g, inv.plant.actual, t, sat, i_w)
+        prev, i_w, sat = d.target_w, d.i_w, d.sat_count
+        inv.command(d.target_w)
+        site.settle(tick_s, dt=0.05)
+        print(f"   {c * tick_s:5.0f} {g:9.0f} {d.target_w:9.0f} "
+              f"{site.battery:9.0f} {site.grid:9.0f}  {d.reason}")
+    print("\n   ⚠️ THE BATTERY NEVER PASSES 5000 W HERE AND CANNOT: plantsim.Plant")
+    print("      clamps at its rating. The -5154 W figure is NOT reproducible in")
+    print("      this model at any tuning, so nothing in this card is graded on it.")
+    print("      What IS reproduced is the setpoint stepping 1000 W a tick to the")
+    print("      rail, and the meter crossing from export into import.")
+
+
+def slew_table(ps, ct, tick_s, rail):
+    frac = ct.SLEW_RAIL_FRAC
+    print(f"THE DERIVATION - gain 0.6, site rail {rail:.0f} W, {tick_s:.0f} s tick, "
+          f"51 export steps 1.0-4.2 kW\n")
+    print(f"  the constraint: the loop must not cross its whole output range "
+          f"faster than the")
+    print(f"  plant settles. {rail:.0f} W / ({ct.PLANT_SETTLE_S:.0f} s / "
+          f"{tick_s:.0f} s per tick) = {frac * rail:.0f} W per tick.\n")
+    for slew in (1000, 800, 700, 600, int(frac * rail), 500, 400, 300, 250):
+        w = family(ps, ct, gain=0.6, slew_w=float(slew), rail_w=rail,
+                   tick_s=tick_s)
+        tag = "   <- the derived value" if slew == int(frac * rail) else (
+              "   <- the 2026-09-05 live pair" if slew == 1000 else (
+              "   <- the live interim" if slew == 400 else ""))
+        row(f"slew_w {slew}{tag}", w)
+    print("\n  READ IT THIS WAY. The >= 900 W step - the live symptom, which")
+    print("  escalated 2 -> 1 -> 13 -> 43 per 30 min that morning - is gone from")
+    print("  every run below 900 W of slew, and that is what the slew owns.")
+    print("  The OVER-ABSORPTION does not move, and at the slowest slews it is")
+    print("  slightly WORSE. The rig cannot pick the derived value out of that")
+    print("  column, and it is not asked to: the CONSTRAINT picks it, and this")
+    print("  table is what says what the constraint does and does not buy.")
+
+
+def gain_table(ps, ct, tick_s, rail):
+    frac = ct.SLEW_RAIL_FRAC
+    print(f"WHAT THE SLEW DOES NOT OWN - slew_w at the derived "
+          f"{frac * rail:.0f} W, gain swept\n")
+    for gain in (0.6, 0.5, 0.4, 0.3, 0.2, 0.1):
+        w = family(ps, ct, gain=gain, slew_w=frac * rail, rail_w=rail,
+                   tick_s=tick_s)
+        row(f"gain {gain}" + ("   <- shipped" if gain == 0.6 else ""), w)
+    print("\n  `slew_w` bounds the OUTPUT. The integrator accumulates")
+    print("  `gain * error` per cycle and is bounded only by `integrator_max_w`,")
+    print("  so at gain 0.6 into a 3.4 kW error it moves ~2000 W per tick and")
+    print(f"  reaches the {rail:.0f} W rail in under three ticks WHATEVER the slew is.")
+    print("  The over-absorption is therefore a GAIN term. `gain: 0.6` is the")
+    print("  next constant to re-derive; SAFETY-39 measured it and changed")
+    print("  nothing, because two control-law constants moving in one release on")
+    print("  a running house makes the next measurement uninterpretable.")
+
+
+def roster_table(ps, ct, tick_s):
+    frac = ct.SLEW_RAIL_FRAC
+    print("N=1 -> N=2: THE RAIL IS WHAT MOVED\n")
+    print("  ⚠️ INVERTER B DOES NOT EXIST (SPIKE-04, ~2026-09-12) AND")
+    print("     plantsim.INVERTER_B IS INVERTER A COPIED, measured=False. The")
+    print("     N=2 rows are therefore about TWO COPIES OF A on a 10000 W rail.")
+    print("     The site B actually implies is ~9600 W (5000 + 4600), and 4600 is")
+    print("     B's DATASHEET and SERIAL, not a measurement, and may be DC -")
+    print("     goodwe/NOTES.md §1.1b. Read the rows as architecture, not as a")
+    print("     prediction about this house.\n")
+    for n, rail in ((1, 5000.0), (2, 10000.0)):
+        for slew in (1000.0, frac * rail):
+            w = family(ps, ct, gain=0.6, slew_w=slew, rail_w=rail, n=n,
+                       tick_s=tick_s)
+            lab = (f"n={n} rail {rail:.0f} slew {slew:.0f}"
+                   + ("  [B = A COPIED]" if n == 2 else ""))
+            row(lab, w)
+    print(f"\n  The derived value at the REAL 9600 W site is "
+          f"{frac * 9600:.0f} W per tick, and")
+    print("  validate.py reads it off `sum(unit_caps(opts))` - the same number")
+    print("  `Controller.site_max_w` builds - so adding inverter B moves the")
+    print("  bound with no operator action and no second derivation.")
+    print("\n  ⚠️ AND THE DIRECTION IS NOT THE ONE THE TICKET ASSUMED. A rail that")
+    print("  GROWS loosens this bound: slew_w 1000 crosses a 9600 W rail in")
+    print("  19.2 s and PASSES, while at 5000 W the same 1000 is the")
+    print("  configuration that was measured failing. That is what the")
+    print("  constraint says and it is correct - the bound is on how long the")
+    print("  crossing TAKES, and a bigger rail at the same step size takes")
+    print("  longer to cross.")
+    print("\n  ⚠️ AND THE >= 900 W STEP COUNT STAYS AT 48/51 AT THE DERIVED VALUE")
+    print("  ON THE N=2 ROW, WHICH IS NOT A FAILURE - IT IS THE THRESHOLD GOING")
+    print("  STALE, on the same day and in the same way as the constant. 900 W")
+    print("  was a meaningful step against a 5000 W rail; against 10000 W the")
+    print("  derived step IS 1111 W, and a check written on the absolute 900")
+    print("  would report the correct tuning as broken. Anything grading this")
+    print("  symptom at N>=2 has to grade it as a FRACTION of the rail too.")
+    print("\n  WHAT DOES NOT GET WORSE HERE, STATED BECAUSE IT WAS EXPECTED TO.")
+    print("  Over the SAME family of 1.0-4.2 kW export steps, doubling the rail")
+    print("  does not worsen the over-absorption (958 -> 810 W): the extra rail")
+    print("  is headroom these disturbances never ask for. That is a statement")
+    print("  about this family, not about the site - a bigger site sees bigger")
+    print("  steps, and the over-absorption is a `gain` term either way, which")
+    print("  the enforced ratio does not bound and this card did not change.")
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--repro", action="store_true")
+    ap.add_argument("--slew", action="store_true")
+    ap.add_argument("--gain", action="store_true")
+    ap.add_argument("--roster", action="store_true")
+    ap.add_argument("--all", action="store_true")
+    ap.add_argument("--tick", type=float, default=None,
+                    help="seconds per control cycle (default: control.LOOP_TICK_S)")
+    ap.add_argument("--rail", type=float, default=5000.0)
+    a = ap.parse_args()
+    if not any((a.repro, a.slew, a.gain, a.roster, a.all)):
+        a.all = True
+    sim = find_sim()
+    if sim is None:
+        sys.exit("slew_sim: admin/goodwe's sim/ is not beside this checkout, so "
+                 "plantsim.Plant is unavailable. Clone it as a sibling or set "
+                 "$GOODWE_SIM. This is a missing repository, NOT a result about "
+                 "the control law - do not report it as one.")
+    ps, ct = load(sim)
+    tick = a.tick if a.tick is not None else ct.LOOP_TICK_S
+    print(f"slew_sim: plant from {sim}")
+    print(f"          control law from {ADDON / 'goodwe_controller' / 'app'}")
+    print(f"          {ps.Inverter.from_spec('A', ps.INVERTER_A).describe()}")
+    print(f"          tick {tick:.1f} s, SLEW_RAIL_FRAC {ct.SLEW_RAIL_FRAC:.4f} "
+          f"= {ct.LOOP_TICK_S:.0f} s / {ct.PLANT_SETTLE_S:.0f} s\n")
+    if a.repro or a.all:
+        repro(ps, ct, tick); print()
+    if a.slew or a.all:
+        slew_table(ps, ct, tick, a.rail); print()
+    if a.gain or a.all:
+        gain_table(ps, ct, tick, a.rail); print()
+    if a.roster or a.all:
+        roster_table(ps, ct, tick)
+
+
+if __name__ == "__main__":
+    main()

goodwe_controller/tools/supervisor_shape_probe.py

@@ -40,8 +40,24 @@ DECISIONS/CFG-04-inverter-roster.md:
      reconstruction happens to lack FIRST, which is an artefact of the
      reconstruction and NOT evidence about `inverters`. B is that evidence.
   C. A two-inverter blob validates, per-entry types enforced.
-  D. An entry missing `name`, `setpoint_entity` or `max_w` is refused BY NAME,
-     and a JSON string where the list belongs is refused outright.
+  D. An entry missing `name`, `setpoint_entity`, `max_w` or `bms_soc_floor` is
+     refused BY NAME - one key varied from an ACCEPTED baseline, and the key's
+     own name asserted in the refusal - and a JSON string where the list belongs
+     is refused outright.
+
+⚠️ RE-RUN 2026-09-04 FOR SAFETY-32, which made `bms_soc_floor` a REQUIRED
+per-entry key. That change broke §C and, worse, left §D printing PASS on a
+refusal about the WRONG KEY - the exact decay MUTATION.md habit 8 describes. §C
+now carries the key and §D is an isolated counterfactual asserting the key name.
+
+⚠️ RE-RUN AGAIN 2026-09-05, on the same 2026.08.0 image, because SAFETY-32's
+rebase onto SPIKE-04a merged two independent edits into §C and §D - the required
+`bms_soc_floor` and inverter B's datasheet `max_w: 4600`. A transcript stitched
+together by hand from two runs is not a measurement, so this one was measured:
+`all cases passed`, exit 0. B's 4600 W is STILL its DATASHEET figure and not a
+reading off any unit, and B's `bms_soc_floor: 15` in §C is illustrative - it
+differs from A's 10 so that the per-entry number is exercised at all, while
+production is expected to have BOTH packs at 10 %.
 """
 import sys, json, copy
 sys.path.insert(0, "/usr/src/supervisor")
@@ -145,13 +161,47 @@ show("the same blob MERGED with these defaults - what App.options actually is",
      f"max_w={out.get('max_w')!r}" if ok else out)
 
 print("\n== C. AC2: a two-inverter blob an operator would POST ==")
+# ⚠️ B's 4600 W IS FROM ITS DATASHEET, NOT A PLACEHOLDER AND NOT A MEASUREMENT.
+# SPIKE-04a (2026-09-04) identified inverter B from the owner's model number and
+# serial - a GoodWe GW5048D-ES, serial `55048ESU22AW0992` - and the datasheet's
+# Max. Charging / Discharging Power is 4600 W. The 3000 W that stood here was a
+# hypothesis from before the unit was known and was simply wrong; the 5000 VA AC
+# nameplate is wrong for this purpose too, because nothing will be connected to
+# B's MPPTs so the battery path is the ceiling. See goodwe/NOTES.md §1.1b.
+#
+# ⚠️ AND IT IS STILL NOT MEASURED. The datasheet prints 4600 W under BATTERY
+# INPUT DATA, so it is probably DC, while `max_w` is graded against 0x0518 - the
+# inverter's own AC power. If it is DC the AC ceiling is nearer 4600 x 0.94 =
+# 4324 W. NOTES.md §1.1b records both readings without picking one, and
+# SAFETY-20's `min(max_w, dev_max)` is what bounds it correctly once dev_max is
+# read off the unit. So this blob is what an operator would POST TODAY, not a
+# claim about what inverter B will turn out to do.
+#
+# ⚠️ THE TWO RATINGS ARE STILL DIFFERENT (5000 / 4600) AND MUST STAY DIFFERENT.
+# This file's own §B is the record of what an instrument that cannot distinguish
+# its two cases is worth. Note that 5000/4600 is a much NARROWER separation than
+# the 5000/3000 it replaces - fine here, where nothing computes on the numbers,
+# and NOT fine in the test fixtures, which is why those keep a wide illustrative
+# pair instead of the real one.
+#
+# ⚠️ AND `bms_soc_floor` IS A REQUIRED PER-ENTRY KEY SINCE SAFETY-32, so this
+# blob is also what proves an operator can still POST a two-inverter config
+# after that. THE TWO FLOORS DIFFER ON PURPOSE (10 and 15): equal values would
+# not exercise a per-entry number at all, for the same reason the two ratings
+# must stay different.
+# ⚠️ NEITHER OF B'S NUMBERS IS A MEASUREMENT OF A PACK. Only inverter A's 10 %
+# is read off hardware (register 0x0560 on the reference GW5000S-BP). B's 4600 W
+# is its DATASHEET figure and B's 15 % is an illustrative value chosen to differ
+# - there is no second pack on this site, and in production BOTH packs are
+# expected to floor at 10 %, which is why the differing pair lives here and in
+# the fixtures rather than in config.yaml's example.
 TWO = dict(LIVE, setpoint_entity="", inverters=[
     {"name": "inverter-a", "setpoint_entity": "number.goodwe_a_setpoint_w",
      "soc_entity": "sensor.goodwe_a_soc", "batt_entity": "sensor.goodwe_a_battery_power",
-     "max_w": 5000},
+     "max_w": 5000, "bms_soc_floor": 10},
     {"name": "inverter-b", "setpoint_entity": "number.goodwe_b_setpoint_w",
      "soc_entity": "sensor.goodwe_b_soc", "batt_entity": "sensor.goodwe_b_battery_power",
-     "max_w": 3000}])
+     "max_w": 4600, "bms_soc_floor": 15}])
 ok, out = validate(MERGER.merge(copy.deepcopy(defaults), copy.deepcopy(TWO)))
 show("two inverters", ok, json.dumps(out.get("inverters")) if ok else out)
 # The validated blob, for anyone who wants to POST it. Optional: the probe's
@@ -162,14 +212,38 @@ except OSError:
     pass
 
 print("\n== D. what the schema itself refuses, per entry ==")
-for title, entry in (
-        ("no name", {"setpoint_entity": "number.b", "max_w": 3000}),
-        ("no setpoint_entity", {"name": "inverter-b", "max_w": 3000}),
-        ("no max_w", {"name": "inverter-b", "setpoint_entity": "number.b"}),
-        ("max_w over the range", {"name": "inverter-b", "setpoint_entity": "number.b", "max_w": 9999})):
-    ok, out = validate(dict(TWO, inverters=[entry]))
-    show(f"an entry with {title} is refused", not ok, out)
-ok, out = validate(dict(TWO, inverters="[]"))
+# ⚠️ ONE KEY VARIED FROM AN ACCEPTED BASELINE, AND THE REFUSAL IS ASSERTED BY
+# NAME - §B's two lessons, applied here because SAFETY-32 is what broke this
+# section. These entries used to omit several keys at once and assert a bare
+# `not ok`; the moment `bms_soc_floor` became required, the "no max_w" case went
+# on printing PASS while the refusal it printed said `Missing option
+# 'bms_soc_floor'`. A refusal of unknown provenance is not a measurement of
+# anything, so the baseline below is COMPLETE and each case deletes exactly one
+# key - or, for the range case, moves exactly one value out of range.
+D_FULL = {"name": "inverter-b", "setpoint_entity": "number.b", "max_w": 4600,
+          "bms_soc_floor": 10}
+# MERGED with the shipped defaults, exactly as §C is and as App.options is: the
+# raw LIVE blob is missing root keys unrelated to this section (`maintenance_
+# start_hour` on the run that caught it), and a baseline refused for one of THOSE
+# is the provenance problem §B2 is kept as a warning about.
+D_BASE = MERGER.merge(copy.deepcopy(defaults), copy.deepcopy(TWO))
+ok, out = validate(dict(D_BASE, inverters=[D_FULL]))
+show("the per-entry BASELINE is ACCEPTED, so every refusal below has nowhere "
+     "else to come from", ok, json.dumps(out.get("inverters")) if ok else out)
+for title, entry, expect in (
+        ("no name", {k: v for k, v in D_FULL.items() if k != "name"}, "name"),
+        ("no setpoint_entity",
+         {k: v for k, v in D_FULL.items() if k != "setpoint_entity"}, "setpoint_entity"),
+        ("no max_w", {k: v for k, v in D_FULL.items() if k != "max_w"}, "max_w"),
+        ("no bms_soc_floor (SAFETY-32)",
+         {k: v for k, v in D_FULL.items() if k != "bms_soc_floor"}, "bms_soc_floor"),
+        ("max_w over the range", dict(D_FULL, max_w=9999), "at most 5000"),
+        ("bms_soc_floor over the range (SAFETY-32)",
+         dict(D_FULL, bms_soc_floor=99), "at most 50")):
+    ok, out = validate(dict(D_BASE, inverters=[entry]))
+    show(f"an entry with {title} is refused, and the refusal NAMES it",
+         (not ok) and expect in str(out), out)
+ok, out = validate(dict(D_BASE, inverters="[]"))
 show("a JSON STRING where the list belongs is refused", not ok, out)
 
 
@@ -198,6 +272,180 @@ except Exception as e:  # noqa: BLE001
     show("Supervisor's UI renderer survives the shape", False, f"{type(e).__name__}: {e}")
 
 
+print("\n== F. UX-01: the TRANSLATED Configuration tab, rendered ==")
+# ⚠️ WHAT THIS SECTION MEASURES, AND WHY IT IS NOT AN ASSERTION ABOUT A FILE.
+# UX-01 adds translations/en.yaml and translations/nl.yaml. Whether they reach
+# an operator depends on two pieces of somebody else's software, not on us:
+#
+#   1. SUPERVISOR decides whether a file is loaded at all.
+#      `supervisor/store/data.py:_read_app_translations()` globs this directory,
+#      keys each file by its STEM, and runs it through `SCHEMA_APP_TRANSLATIONS`.
+#      ⚠️ A FILE THAT FAILS THAT SCHEMA IS DROPPED WITH A LOG WARNING AND
+#      NOTHING ELSE: `except (ConfigurationFileError, vol.Invalid): _LOGGER.
+#      warning(...); continue`. The add-on then renders raw keys and the only
+#      trace is one line in the Supervisor log. So the loader is RUN here, out
+#      of the release image, rather than the schema being re-implemented.
+#   2. THE FRONTEND decides what it does with what Supervisor loaded. The
+#      resolution below is not invented: it is transcribed from the shipped
+#      bundle in THIS image, `api/panel/frontend_latest/5680.*.js`
+#      (frontend 20250925.1), which reads
+#
+#        _getTranslationEntry(lang,s,o){let e=this.addon.translations[lang]?.
+#            configuration; if(e){if(o?.path)for(const t of o.path)
+#            if(e=e[t]?.fields,!e)return; return e[s.name]}}
+#        computeLabel =(s,_,o)=>this._getTranslationEntry(this.hass.language,s,o)?.name
+#                             ||this._getTranslationEntry("en",s,o)?.name||s.name
+#        computeHelper=(s,o)  =>this._getTranslationEntry(this.hass.language,s,o)?.description
+#                             ||this._getTranslationEntry("en",s,o)?.description||""
+#        _filteredSchema=(opts,schema)=>schema.filter(e=>e.name in opts||e.required)
+#
+#      i.e. the fallback is PER KEY, en is the second chance, and the raw key
+#      name is the third.
+from supervisor.apps.validate import SCHEMA_APP_TRANSLATIONS   # noqa: E402
+from supervisor.store.data import _read_app_translations       # noqa: E402
+
+TRANSLATIONS = _read_app_translations(Path("/w"))
+show("Supervisor's OWN translation loader accepts both files - a file that "
+     "fails SCHEMA_APP_TRANSLATIONS is DROPPED with a log warning and the tab "
+     "silently goes back to raw keys, so 'it is on disk' is not the question",
+     set(TRANSLATIONS) == {"en", "nl"}, sorted(TRANSLATIONS))
+
+ui = UiOptions(None)(schema)
+print(f"  the Configuration tab renders {len(ui)} fields, in `schema:` order "
+      "(App.schema_ui is UiOptions(...)(data['schema']), so the ORDER IS THE "
+      "SCHEMA BLOCK'S and not the options block's)")
+
+
+def _entry(lang, name, path=()):
+    node = TRANSLATIONS.get(lang, {}).get("configuration")
+    if not node:
+        return None
+    for step in path:
+        node = (node.get(step) or {}).get("fields")
+        if not node:
+            return None
+    return node.get(name)
+
+
+def _label(lang, name, path=()):
+    for lg in (lang, "en"):
+        e = _entry(lg, name, path)
+        if e and e.get("name"):
+            return e["name"], lg
+    return name, "RAW KEY"
+
+
+def _helper(lang, name, path=()):
+    for lg in (lang, "en"):
+        e = _entry(lg, name, path)
+        if e and e.get("description"):
+            return e["description"], lg
+    return "", "NONE"
+
+
+# ⚠️ EVERY FIELD, PRINTED. This is the transcript the card asks for: what the
+# owner's Supervisor puts on the screen, not a claim that it would look nice.
+for lang in ("en", "nl"):
+    print(f"\n  --- as rendered at hass.language == {lang!r} "
+          f"(the owner's HA runs Europe/Brussels) ---")
+    for node in ui:
+        lbl, src = _label(lang, node["name"])
+        hlp, hsrc = _helper(lang, node["name"])
+        flag = "" if src == lang else f"   [name from {src}]"
+        print(f"    {node['name']:28s} -> {lbl}{flag}")
+        print(f"    {'':28s}    {hlp[:150]}{'...' if len(hlp) > 150 else ''}")
+        for sub in node.get("schema", ()):
+            slbl, ssrc = _label(lang, sub["name"], (node["name"],))
+            print(f"      · {sub['name']:24s} -> {slbl}"
+                  + ("" if ssrc == lang else f"   [{ssrc}]"))
+
+_raw = [n["name"] for n in ui if _label("en", n["name"])[1] == "RAW KEY"]
+show("NOT ONE top-level field falls through to its raw key name in `en` - "
+     f"which is what the tab rendered for all {len(ui)} of them before this "
+     f"card, because there was no translations/ directory at all. Raw: {_raw}",
+     not _raw)
+_nohelp = [n["name"] for n in ui if not _helper("en", n["name"])[0]]
+show("...and not one is left without a description, which is the half that "
+     f"says WHETHER TO TOUCH IT. Missing: {_nohelp}", not _nohelp)
+_nl_missing = [n["name"] for n in ui if _label("nl", n["name"])[1] != "nl"]
+show("...and every one of them is translated in `nl` too, so nothing on the "
+     f"owner's own screen falls back to English. Falling back: {_nl_missing}",
+     not _nl_missing)
+
+# ⚠️ THE HONEST HALF, AND IT IS A NEGATIVE RESULT. `inverters` is a
+# list-of-objects, so UiOptions gives it type "schema" WITH multiple: True, and
+# `_convertSchemaElement` sends exactly that case to a SELECTOR rather than to a
+# nested ha-form:
+#
+#   if("schema"===t.type&&!t.multiple) return {...type:"expandable"...}   <- not us
+#   if("schema"===t.type){const o={};for(const a of t.schema)
+#       o[a.name]={required:a.required,selector:...}; return {object:{multiple:t.multiple,fields:o}}}
+#
+# and ha-selector-object labels those fields with
+#
+#   computeLabel=e=>{const t=this.selector.object?.translation_key;
+#       if(this.localizeValue&&t){...}
+#       return this.selector.object?.fields?.[e.name]?.label||e.name}
+#
+# `_convertSchemaElementToSelector` sets neither `label` nor `translation_key`,
+# so ON THIS FRONTEND the per-entry keys inside the repeatable section render as
+# `setpoint_entity`, `max_w`, `bms_soc_floor` - RAW - however well they are
+# translated here. The `fields:` block is still shipped and still validated,
+# because it is the shape Supervisor's own schema defines for exactly this and
+# it is what a frontend that wires `label` through would consume; but this card
+# must not claim it reaches the operator today, and the count below is asserted
+# so that the day it changes, this transcript says so.
+_multi = [n for n in ui if n.get("multiple") and n.get("type") == "schema"]
+show("`inverters` is rendered as a REPEATABLE SECTION (type schema, multiple), "
+     "which is CFG-04's measurement re-confirmed", 
+     [n["name"] for n in _multi] == ["inverters"], json.dumps(_multi)[:200])
+show("⚠️ MEASURED AND NEGATIVE: this frontend gives that section's per-entry "
+     "keys to ha-selector-object, which labels them `fields[name].label || "
+     "name` - and the converter sets no `label` and no `translation_key`. So "
+     "the per-entry translations below are SHIPPED AND VALIDATED but do NOT "
+     "reach the screen on 20250925.1. The top-level `inverters` label and "
+     "description DO.",
+     bool(_multi) and all("label" not in s and "translation_key" not in s
+                          for n in _multi for s in n.get("schema", ())),
+     "per-entry keys as rendered today: "
+     + ", ".join(s["name"] for n in _multi for s in n.get("schema", ())))
+
+# ⚠️ AND THE HAND PARSER CI USES IS GRADED AGAINST THIS LOADER, KEY BY KEY.
+# test_translations.py runs in the add-on's CI image, which has no PyYAML, so it
+# parses these files with tools/translations_lint.py. A hand parser that
+# disagrees with the real loader is a check whose data cannot reach the failure
+# it names, so the two are compared here - where both are available - rather
+# than assumed to agree.
+sys.path.insert(0, "/probe")
+import translations_lint as _tl                                # noqa: E402
+_mismatch = []
+for lang in ("en", "nl"):
+    hand = _tl.parse_translation_file(f"/w/translations/{lang}.yaml")
+    real = {"configuration": TRANSLATIONS[lang].get("configuration", {})}
+    # SCHEMA_APP_TRANSLATIONS fills `description: None` for an absent one; the
+    # hand parser simply has no key. Normalise that ONE difference and nothing
+    # else, so a real disagreement cannot hide behind the normalisation.
+    def _norm(d):
+        return {k: {kk: vv for kk, vv in v.items() if vv is not None
+                    and kk != "fields"}
+                | ({"fields": _norm(v["fields"])} if v.get("fields") else {})
+                for k, v in d.items()}
+    if _norm(hand.get("configuration", {})) != _norm(real["configuration"]):
+        a, b = _norm(hand.get("configuration", {})), _norm(real["configuration"])
+        _mismatch += [f"{lang}:{k}" for k in sorted(set(a) | set(b))
+                      if a.get(k) != b.get(k)]
+show("the hand parser CI uses (tools/translations_lint.py) returns EXACTLY "
+     "what Supervisor's own loader returns, for both files, key by key and "
+     f"string by string. Disagreements: {_mismatch}", not _mismatch)
+_cfg_text = Path("/w/config.yaml").read_text(encoding="utf-8")
+_probs = []
+for lang in ("en", "nl"):
+    _probs += _tl.audit(
+        _cfg_text,
+        {"configuration": TRANSLATIONS[lang].get("configuration", {})}, lang)
+show(f"...and the coverage audit is clean against the real loader's view too. "
+     f"Problems: {_probs}", not _probs)
+
 # ⚠️ THE EXIT CODE IS PART OF THE INSTRUMENT. Without it the probe prints FAIL
 # and still succeeds, and a transcript is only evidence if a wrong answer is
 # distinguishable from a right one by something other than reading it.

goodwe_controller/tools/symmetric_message_scan.py

@@ -0,0 +1,878 @@
+#!/usr/bin/env python3
+"""SAFETY-38 round 3 - the SYMMETRIC-PREDICATE FAMILY, enumerated by machine.
+
+WHAT IT LOOKS FOR, in one sentence: a call whose argument ORDER is load-bearing
+for a MESSAGE and for nothing else - so swapping the arguments cannot change a
+single decision, is invisible to every behavioural check BY CONSTRUCTION, and
+still inverts what an operator reads on the line they are woken by.
+
+⚠️ WHY IT IS AN INSTRUMENT AND NOT A LIST. MUTATION.md habit 12: "a hand-written
+scope is the same defect as a hand-written fixture". SAFETY-38 met this family
+twice - `SignWatchdog.evaluate()` called at `main.py:1620` (round 2) and at
+`main.py:1560` (round 3), ONE CALL SITE OVER - and both times the enumeration
+was written by hand and both times it was short. So the scope is computed.
+
+------------------------------------------------------------------------------
+THE TEST IT APPLIES
+
+For every function in `app/` and every pair (a, b) of its parameters:
+
+    rename a -> b and b -> a throughout the body, ERASE every string literal
+    and f-string, CANONICALISE the commutative operators, and compare the two
+    ASTs. If they are EQUAL, nothing the function DECIDES can depend on which
+    of the two values arrived first.
+
+Then, if some f-string in that function mentions BOTH names, the order is
+load-bearing for the MESSAGE ALONE, and the pair is reported.
+
+⚠️ THE SYMMETRY IS USUALLY ONE CALL DEEP, WHICH IS WHY THIS IS A FIXPOINT AND
+NOT A SINGLE PASS. `SignWatchdog.evaluate()` does not compare its two arguments
+itself; it hands them to `watchdog.disagrees()`, whose body is
+`commanded_w * against_w < 0 and abs(commanded_w) > min_w and
+abs(against_w) > min_w`. An intraprocedural scan sees `disagrees(a, b, ...)`
+become `disagrees(b, a, ...)`, calls that a difference, and reports NOTHING -
+which is exactly what the first version of this file did, on a tree where the
+answer was already known. So symmetric pairs discovered in one round are used
+to canonicalise CALL ARGUMENTS in the next, and the scan iterates until the set
+stops growing.
+
+CANONICALISATION, and each entry is here because something in `app/` needs it:
+  * `a * b`, `a + b`               - operand order sorted (`disagrees`)
+  * `x and y`, `x or y`            - term order sorted (`disagrees`' conjunction)
+  * `a == b`, `a != b`             - operand order sorted
+  * `min(a, b)`, `max(a, b)`       - argument order sorted (`clamp_to_rating`)
+  * a tuple/list/set LITERAL being iterated - element order sorted
+    (`rail_ceiling_w`'s `for bound in (dev_min, dev_max)`)
+  * arguments at a KNOWN SYMMETRIC POSITION PAIR of a called function - sorted
+    (the fixpoint)
+
+Equal ASTs after the rename is a SUFFICIENT condition for behavioural
+invariance, not a necessary one. This scan therefore UNDER-REPORTS and says so
+- see "WHAT THIS CANNOT SEE". That is the conservative direction: everything it
+names is genuinely in the family, and the gap is stated with its shape.
+
+Run: `python3 tools/symmetric_message_scan.py [--quiet]` from goodwe_controller/.
+Exit status is 0 always; it is a census, not a gate.
+"""
+from __future__ import annotations
+
+import ast
+import itertools
+import pathlib
+import sys
+
+APP = pathlib.Path(__file__).resolve().parent.parent / "app"
+
+# {function name: {(i, j) positional index pairs that are interchangeable}}
+_SYM: dict[str, set[tuple[int, int]]] = {}
+# ⚠️ AND THE SAME THING FOR KEYWORD-ONLY PARAMETERS, WHICH THE FIRST FIXPOINT
+# DROPPED. `freeze.rail_ceiling_w(max_w, *, dev_min=None, dev_max=None)` folds
+# its two device bounds with `for bound in (dev_min, dev_max): ceiling = min(
+# ceiling, abs(bound))` - perfectly symmetric - and `rail_unreachable()` prints
+# `"a range of {dev_min}...{dev_max} W"`. A scan that only followed POSITIONAL
+# arguments called that pair asymmetric and hid a genuine member of the family
+# behind an implementation detail of its own traversal.
+_SYM_KW: dict[str, set[tuple[str, str]]] = {}
+
+
+class _Canon(ast.NodeTransformer):
+    """Rename one pair, erase every string, and sort what commutes."""
+
+    COMMUTATIVE_BINOP = (ast.Mult, ast.Add, ast.BitAnd, ast.BitOr, ast.BitXor)
+    COMMUTATIVE_CMP = (ast.Eq, ast.NotEq)
+    COMMUTATIVE_CALL = ("min", "max")
+
+    def __init__(self, a: str = "", b: str = ""):
+        self.a, self.b = a, b
+
+    # -- the rename ---------------------------------------------------------
+    def visit_Name(self, node):
+        self.generic_visit(node)
+        if self.a and node.id == self.a:
+            node.id = self.b
+        elif self.b and node.id == self.b:
+            node.id = self.a
+        return node
+
+    def visit_arg(self, node):
+        if self.a and node.arg == self.a:
+            node.arg = self.b
+        elif self.b and node.arg == self.b:
+            node.arg = self.a
+        return node
+
+    # -- the message is exactly what is ALLOWED to differ --------------------
+    def visit_JoinedStr(self, node):
+        return ast.Constant(value="<msg>")
+
+    def visit_Constant(self, node):
+        if isinstance(node.value, str):
+            return ast.Constant(value="<msg>")
+        return node
+
+    # -- canonicalisation ---------------------------------------------------
+    def visit_BinOp(self, node):
+        self.generic_visit(node)
+        if isinstance(node.op, self.COMMUTATIVE_BINOP):
+            l, r = ast.dump(node.left), ast.dump(node.right)
+            if l > r:
+                node.left, node.right = node.right, node.left
+        return node
+
+    def visit_BoolOp(self, node):
+        self.generic_visit(node)
+        node.values = sorted(node.values, key=ast.dump)
+        return node
+
+    def visit_Compare(self, node):
+        self.generic_visit(node)
+        if (len(node.ops) == 1
+                and isinstance(node.ops[0], self.COMMUTATIVE_CMP)):
+            l, r = ast.dump(node.left), ast.dump(node.comparators[0])
+            if l > r:
+                node.left, node.comparators[0] = node.comparators[0], node.left
+        return node
+
+    def visit_For(self, node):
+        self.generic_visit(node)
+        if isinstance(node.iter, (ast.Tuple, ast.List, ast.Set)):
+            node.iter.elts = sorted(node.iter.elts, key=ast.dump)
+        return node
+
+    def visit_Call(self, node):
+        self.generic_visit(node)
+        name = (node.func.id if isinstance(node.func, ast.Name)
+                else node.func.attr if isinstance(node.func, ast.Attribute)
+                else "")
+        if name in self.COMMUTATIVE_CALL and len(node.args) == 2 \
+                and not node.keywords:
+            if ast.dump(node.args[0]) > ast.dump(node.args[1]):
+                node.args = [node.args[1], node.args[0]]
+            return node
+        # the fixpoint: sort the arguments at a known symmetric position pair
+        for (i, j) in sorted(_SYM.get(name, ())):
+            if j < len(node.args):
+                if ast.dump(node.args[i]) > ast.dump(node.args[j]):
+                    node.args[i], node.args[j] = node.args[j], node.args[i]
+        # ...and at a known symmetric KEYWORD pair
+        for (ka, kb) in sorted(_SYM_KW.get(name, ())):
+            ia = next((k for k, w in enumerate(node.keywords)
+                       if w.arg == ka), None)
+            ib = next((k for k, w in enumerate(node.keywords)
+                       if w.arg == kb), None)
+            if ia is not None and ib is not None:
+                va, vb = node.keywords[ia].value, node.keywords[ib].value
+                if ast.dump(va) > ast.dump(vb):
+                    node.keywords[ia].value, node.keywords[ib].value = vb, va
+        return node
+
+
+def _canon(src: str, a: str = "", b: str = "") -> str:
+    return ast.dump(_Canon(a, b).visit(ast.parse(src)))
+
+
+# ⚠️ THE SINK IS HALF THE CLAIM, AND THE FIRST VERSION OF THIS SCAN OMITTED IT.
+# Erasing every f-string makes a function whose ONLY job is to FORMAT one look
+# perfectly symmetric - `store.unit_key(unit, key)` and
+# `mqtt.unit_state_key(slug, key)` both came back as "the swap changes nothing"
+# when in fact the string IS the return value: swapping there renames a STORE
+# KEY and an MQTT TOPIC, which is a behaviour change every ordinary check can
+# see, and MAINT-05 is the card about exactly that. The family this file is
+# looking for is narrower - the string goes to an OPERATOR and to nobody else -
+# so each sentence is classified by where it GOES.
+_LOG_SINKS = {"debug", "info", "warning", "warn", "error", "exception",
+              "critical", "log", "log_event", "notify", "persistent_notify"}
+_MSG_ATTRS = {"reason", "message", "msg", "banner", "detail", "note",
+              "explanation", "why", "text"}
+
+
+def _sink_of(fn, target, follow=True):
+    """RETURN | MESSAGE | OTHER - where this f-string node ends up.
+
+    `follow` is the ONE step of data flow below, and it is off on the recursive
+    call so that two locals that interpolate each other cannot loop forever.
+    """
+    for stmt in ast.walk(fn):
+        for child in ast.iter_child_nodes(stmt):
+            pass
+    # a parent map is cheaper than repeated walks
+    parent = {}
+    for node in ast.walk(fn):
+        for child in ast.iter_child_nodes(node):
+            parent[id(child)] = node
+    cur = target
+    while id(cur) in parent:
+        up = parent[id(cur)]
+        if isinstance(up, ast.Return):
+            return "RETURN"
+        if isinstance(up, ast.Raise):
+            return "MESSAGE"
+        if isinstance(up, (ast.Assign, ast.AnnAssign, ast.AugAssign)):
+            tgts = (up.targets if isinstance(up, ast.Assign) else [up.target])
+            for t in tgts:
+                if isinstance(t, ast.Attribute) and t.attr in _MSG_ATTRS:
+                    return "MESSAGE"
+                if isinstance(t, ast.Name) and t.id in _MSG_ATTRS:
+                    return "MESSAGE"
+            # ⚠️ ONE STEP OF DATA FLOW, AND IT IS NOT OPTIONAL. `main.py`'s
+            # status page builds the device-range clause into a LOCAL - `_cap =
+            # "; ".join(f"... accepts only {inv.dev_min}...{inv.dev_max} W" ...)`
+            # - and only then concatenates it into the row's `text`. Stopping at
+            # the assignment scores that OTHER and drops a member this card
+            # MEASURED as a live survivor (0 bytes, 21/21 green). So: if the
+            # name assigned here is interpolated into some other sentence in the
+            # same function that IS a message, this one is a message too.
+            if follow:
+                for t in tgts:
+                    if isinstance(t, ast.Name) and _feeds_a_message(fn, t.id,
+                                                                    up):
+                        return "MESSAGE"
+            return "OTHER"
+        # ⚠️ ROUND 4. A SENTENCE HANDED TO A CONSTRUCTOR AS `reason=` IS A
+        # MESSAGE, and scoring only ASSIGNMENTS missed every one of them. This
+        # codebase builds most of its operator sentences that way -
+        # `ArbitrageDecision(action=..., reason=f"...")`,
+        # `out.append({"text": f"..."})` - so the sentence never touches a name
+        # this walker was watching. arbitrage.py's two DISCHARGE/CHARGE reasons
+        # were scored OTHER for exactly this and are genuine members.
+        if isinstance(up, ast.keyword) and up.arg in _MSG_ATTRS:
+            return "MESSAGE"
+        if isinstance(up, ast.Dict):
+            for k, v in zip(up.keys, up.values):
+                if (v is cur and isinstance(k, ast.Constant)
+                        and k.value in _MSG_ATTRS):
+                    return "MESSAGE"
+        if isinstance(up, ast.Call):
+            name = (up.func.attr if isinstance(up.func, ast.Attribute)
+                    else up.func.id if isinstance(up.func, ast.Name) else "")
+            if name in _LOG_SINKS:
+                return "MESSAGE"
+            if name == "append":
+                return "MESSAGE"
+        cur = up
+    return "OTHER"
+
+
+def _feeds_a_message(fn, name, origin):
+    """Is `name` interpolated into some OTHER sentence that IS a message?"""
+    for node in ast.walk(fn):
+        if not isinstance(node, ast.JoinedStr) or node is origin:
+            continue
+        used = any(isinstance(x, ast.Name) and x.id == name
+                   for v in node.values if isinstance(v, ast.FormattedValue)
+                   for x in ast.walk(v.value))
+        if used and _sink_of(fn, node, follow=False) == "MESSAGE":
+            return True
+    return False
+
+
+def _fstring_pairs(fn, params):
+    """{(a, b): [(lineno, sink), ...]} for every f-string mentioning both."""
+    out: dict[tuple[str, str], list[tuple[int, str]]] = {}
+    for node in ast.walk(fn):
+        if not isinstance(node, ast.JoinedStr):
+            continue
+        used = set()
+        for v in node.values:
+            if isinstance(v, ast.FormattedValue):
+                for x in ast.walk(v.value):
+                    if isinstance(x, ast.Name) and x.id in params:
+                        used.add(x.id)
+        if len(used) < 2:
+            continue
+        sink = _sink_of(fn, node)
+        for a, b in itertools.combinations(sorted(used), 2):
+            out.setdefault((a, b), []).append((node.lineno, sink))
+    return out
+
+
+def _functions():
+    for path in sorted(APP.glob("*.py")):
+        tree = ast.parse(path.read_text())
+        for fn in ast.walk(tree):
+            if isinstance(fn, (ast.FunctionDef, ast.AsyncFunctionDef)):
+                yield path, fn
+
+
+def _positional(fn):
+    return [a.arg for a in fn.args.posonlyargs + fn.args.args
+            if a.arg != "self"]
+
+
+def _all_params(fn):
+    return _positional(fn) + [a.arg for a in fn.args.kwonlyargs]
+
+
+def _body_src(fn) -> str:
+    """The function's BODY alone.
+
+    ⚠️ NOT `ast.unparse(fn)`. The signature lists the parameters IN ORDER, so
+    renaming a pair inside it reorders `arguments.args` and every function in
+    the repository compares unequal to itself - which is what the first version
+    of this scan did, silently, and it reported an empty family on a tree whose
+    answer was already known. The claim being tested is about what the body
+    DECIDES, and the body is what is compared.
+    """
+    return ast.unparse(ast.Module(body=list(fn.body), type_ignores=[]))
+
+
+def _symmetric(fn, a, b) -> bool:
+    src = _body_src(fn)
+    return _canon(src) == _canon(src, a, b)
+
+
+def build_fixpoint(max_rounds=6):
+    """Fill `_SYM` until it stops growing. Returns the number of rounds."""
+    for round_no in range(1, max_rounds + 1):
+        grew = False
+        for _path, fn in _functions():
+            pos = _positional(fn)
+            kws = [a.arg for a in fn.args.kwonlyargs]
+            if len(pos) + len(kws) < 2:
+                continue
+            found = set()
+            for i, j in itertools.combinations(range(len(pos)), 2):
+                if _symmetric(fn, pos[i], pos[j]):
+                    found.add((i, j))
+            found_kw = set()
+            for ka, kb in itertools.combinations(sorted(kws), 2):
+                if _symmetric(fn, ka, kb):
+                    found_kw.add((ka, kb))
+            if found - _SYM.get(fn.name, set()):
+                _SYM.setdefault(fn.name, set()).update(found)
+                grew = True
+            if found_kw - _SYM_KW.get(fn.name, set()):
+                _SYM_KW.setdefault(fn.name, set()).update(found_kw)
+                grew = True
+        if not grew:
+            return round_no
+    return max_rounds
+
+
+def scan():
+    rows = []
+    for path, fn in _functions():
+        params = _all_params(fn)
+        if len(params) < 2:
+            continue
+        kwonly = {a.arg for a in fn.args.kwonlyargs}
+        for (a, b), hits in sorted(_fstring_pairs(fn, params).items()):
+            rows.append(dict(
+                module=path.name, func=fn.name, line=fn.lineno, a=a, b=b,
+                msg_lines=sorted(set(hits)),
+                sinks={s for _l, s in hits},
+                symmetric=_symmetric(fn, a, b),
+                positional=not (a in kwonly or b in kwonly)))
+    return rows
+
+
+# =============================================================================
+# CENSUS B - THE SENTENCE THE CALLER BUILDS
+# =============================================================================
+# ⚠️ CENSUS A ABOVE ONLY SEES A CALLEE FORMATTING ITS OWN PARAMETERS, AND THAT
+# WAS GAP 2 OF ITS OWN "WHAT THIS CANNOT SEE" LIST. The other half of the family
+# never passes through a function boundary at all: an operator sentence built
+# where it is printed, interpolating two values that are INTERCHANGEABLE BY
+# SHAPE. `main.py`'s status page says
+#
+#     f"{inv.setpoint_entity or inv.name} accepts only {inv.dev_min}...{inv.dev_max} W"
+#
+# and transposing those two costs ZERO BYTES, changes nothing any check can
+# observe, and tells the operator a range backwards. No predicate is involved,
+# so census A's symmetry test has nothing to test.
+#
+# THE TEST: inside one MESSAGE-sink f-string, take every pair of interpolated
+# expressions, blank every attribute NAME and every string CONSTANT, and compare.
+# If the blanked forms are EQUAL while the originals DIFFER, the two expressions
+# are the same shape with one leaf changed - `inv.dev_min` / `inv.dev_max`,
+# `site_dev_bound("dev_min")` / `site_dev_bound("dev_max")` - which is exactly
+# the pair a transposition swaps. Same direction as census A: it under-reports
+# (two values of the same KIND spelled differently are missed) rather than
+# inventing members.
+
+
+
+class _Blank(ast.NodeTransformer):
+    def visit_Attribute(self, node):
+        self.generic_visit(node)
+        node.attr = "<leaf>"
+        return node
+
+    def visit_Constant(self, node):
+        if isinstance(node.value, str):
+            return ast.Constant(value="<leaf>")
+        return node
+
+
+def _blanked(expr):
+    return ast.dump(_Blank().visit(ast.parse(ast.unparse(expr))))
+
+
+def _called_name(func):
+    return (func.attr if isinstance(func, ast.Attribute)
+            else func.id if isinstance(func, ast.Name) else "")
+
+
+def _innermost(tree):
+    """{id(node): INNERMOST enclosing function}, or None at module level.
+
+    ⚠️ NOT `for fn in ast.walk(tree): for node in ast.walk(fn)`, which is what
+    the first version of census B did. That visits every sentence once per
+    ENCLOSING def, so a sentence inside a nested function was classified twice -
+    once against the inner scope and once against the outer - and the two
+    classifications are not obliged to agree. The rows were de-duplicated
+    afterwards, which hid the double visit rather than removing it.
+    """
+    m = {}
+
+    def rec(node, fn):
+        for child in ast.iter_child_nodes(node):
+            f = (child if isinstance(child, (ast.FunctionDef,
+                                             ast.AsyncFunctionDef)) else fn)
+            m[id(child)] = f
+            rec(child, f)
+
+    rec(tree, None)
+    return m
+
+
+def _spec(fv):
+    """The FORMAT SPEC of one interpolation, as text; '' when there is none.
+
+    ⚠️ IT IS PRINTED BESIDE EVERY PAIR BECAUSE IT IS THE ONE CHEAP TYPE SIGNAL
+    THIS SCAN HAS, and gap 4 of the second list below is exactly about the pairs
+    that do not share
+    one. `{self.requested_w:+.0f}` beside `{self.applied_w:+.0f}` is two floats
+    rendered identically - a transposition there is silent and reads as a fact.
+    `{self.limit_w:.0f}` beside `{self.bound}` is a float beside a string: a
+    transposition there prints `rating max_w W`, which is visibly broken rather
+    than quietly wrong. Same row in this census, very different hazard, and the
+    reader cannot tell them apart without this column.
+    """
+    if fv.format_spec is None:
+        return ""
+    return "".join(str(v.value) if isinstance(v, ast.Constant) else "{...}"
+                   for v in fv.format_spec.values)
+
+
+def _same_shape_pairs(node):
+    """Pairs of interpolations in ONE f-string that are exactly one leaf apart."""
+    fvs = [v for v in node.values if isinstance(v, ast.FormattedValue)]
+    for x, y in itertools.combinations(fvs, 2):
+        ua, ub = ast.unparse(x.value), ast.unparse(y.value)
+        if ua == ub:
+            continue
+        if _blanked(x.value) != _blanked(y.value):
+            continue
+        yield ua, ub, _spec(x), _spec(y)
+
+
+def _sentences():
+    """(path, innermost fn, JoinedStr, sink) for every f-string in app/."""
+    for path in sorted(APP.glob("*.py")):
+        tree = ast.parse(path.read_text())
+        inner = _innermost(tree)
+        for node in ast.walk(tree):
+            if not isinstance(node, ast.JoinedStr):
+                continue
+            fn = inner.get(id(node))
+            if fn is None:
+                continue
+            yield path, fn, node, _sink_of(fn, node)
+
+
+def scan_caller():
+    rows = []
+    for path, fn, node, sink in _sentences():
+        # ⚠️ MESSAGE SINKS ONLY, AND THE FIRST VERSION OF THIS CENSUS SAID
+        # "anything but a RETURN". That let in `p1.py`'s
+        # `self.url = f"http://{self.host}:{self.port}…"` - an f-string that is
+        # DATA, used to make a request, where a transposition is an ordinary
+        # behavioural change every check can see. A formatted string is only in
+        # this family when its only consumer is a person. RETURN is not OTHER
+        # though, and treating it as if it were is what census C below fixes.
+        if sink != "MESSAGE":
+            continue
+        for ua, ub, sa, sb in _same_shape_pairs(node):
+            rows.append((path.name, node.lineno, fn.name, ua, ub, sa, sb))
+    return sorted(set(rows), key=lambda r: (r[0], r[1], r[3]))
+
+
+# =============================================================================
+# CENSUS C - THE SENTENCE THE OBJECT RETURNS ABOUT ITSELF
+# =============================================================================
+# ⚠️ SAFETY-38 ROUND 4. CENSUS A AND CENSUS B BETWEEN THEM COVERED ONE
+# SYNTACTIC SINK AND CALLED IT THE FAMILY. Every member either census reported
+# was a sentence APPENDED, ASSIGNED to a `reason`-shaped attribute, or passed as
+# a LOG ARGUMENT. Not one was a sentence that is RETURNED. Census A had a RETURN
+# bucket, but only for a callee formatting its own PARAMETERS - so a method
+# formatting its own ATTRIBUTES and handing the string back was invisible to
+# both, and `describe()` / `explain()` / the reason-builders are precisely where
+# this codebase keeps its operator sentences. Two live members were sitting in
+# that hole:
+#
+#   clamp.py    ClampResult.describe()   requested_w <-> applied_w
+#   peakguard.py PeakDecision.explain()  projected_w <-> ceiling_w
+#
+# Worse than the gap: it was in NONE of the five blind spots this file prints
+# about itself. A tool that asserts a completeness it does not have is the
+# recurring defect in a new hat, and the list at the bottom now names its sinks.
+#
+# THE TEST is census B's - one f-string, two interpolations one leaf apart - run
+# over the RETURN sink, plus one thing census B never needed: A RETURNED STRING
+# IS NOT YET A MESSAGE. `store.unit_key()` and `mqtt.unit_state_key()` return
+# f-strings too, and swapping there renames a store key and an MQTT topic, which
+# every ordinary check can see (MAINT-05 is the card about that). So the sink of
+# a returned sentence is RESOLVED THROUGH ITS CALL SITES: the string is in this
+# family only when some caller in `app/` feeds it to an operator.
+
+
+def _return_consumers(func_name, depth=0, seen=frozenset()):
+    """[(site, sink, verdict)] - where the STRING RETURNED BY `func_name` goes.
+
+    One hop is not enough: `Resolution.explain()` is returned again by wrappers
+    that are themselves logged, so a call site whose own sink is RETURN is
+    resolved by recursing on the ENCLOSING function's name, bounded by `depth`
+    and by `seen` so mutual recursion cannot loop.
+
+    ⚠️ THE MATCH IS ON THE BARE METHOD NAME, exactly as `call_sites()` above,
+    and `explain` is the name of at least four unrelated methods in this tree
+    (`PeakDecision`, `UnitPlan`, `Resolution`, the maintenance migration
+    report). So this OVER-collects sites, which pushes a verdict towards
+    MESSAGE. That is the deliberate direction for a census whose measured
+    failure has twice been under-reporting - but it means the verdict is a
+    PROMPT TO READ THE SITES PRINTED BESIDE IT, not a proof.
+    """
+    if func_name in seen or depth > 2:
+        return []
+    seen = seen | {func_name}
+    out = []
+    for path in sorted(APP.glob("*.py")):
+        tree = ast.parse(path.read_text())
+        inner = _innermost(tree)
+        for node in ast.walk(tree):
+            if not isinstance(node, ast.Call):
+                continue
+            if _called_name(node.func) != func_name:
+                continue
+            fn = inner.get(id(node))
+            if fn is None:
+                continue
+            sink = _sink_of(fn, node)
+            label = f"{path.name}:{node.lineno} `{ast.unparse(node.func)}`"
+            if sink == "RETURN":
+                sub = _return_consumers(fn.name, depth + 1, seen)
+                if any(v == "MESSAGE" for _l, _s, v in sub):
+                    verdict = "MESSAGE"
+                elif not sub:
+                    verdict = "UNRESOLVED"
+                else:
+                    verdict = "OTHER"
+                sink = f"RETURN by {fn.name}() -> {verdict}"
+            else:
+                verdict = sink
+            out.append((label, sink, verdict))
+    return sorted(set(out))
+
+
+def scan_returned():
+    """Census C rows: a returned sentence, two interpolations one leaf apart."""
+    rows = []
+    for path, fn, node, sink in _sentences():
+        if sink != "RETURN":
+            continue
+        pairs = list(_same_shape_pairs(node))
+        if not pairs:
+            continue
+        sites = _return_consumers(fn.name)
+        if any(v == "MESSAGE" for _l, _s, v in sites):
+            verdict = "MESSAGE"
+        elif not sites:
+            verdict = "UNRESOLVED - no call site inside app/"
+        else:
+            verdict = "OTHER"
+        for ua, ub, sa, sb in pairs:
+            rows.append(dict(module=path.name, line=node.lineno, func=fn.name,
+                             a=ua, b=ub, spec_a=sa, spec_b=sb,
+                             verdict=verdict, sites=sites))
+    return sorted(rows, key=lambda r: (r["module"], r["line"], r["a"]))
+
+
+# ⚠️ THE UNIT OF COVERAGE IS THE CALL SITE, NOT THE FUNCTION - which is the
+# whole lesson of SAFETY-38 round 3. `SignWatchdog.evaluate()` had its operand
+# order pinned and the defect still shipped, because the pin was on the call two
+# lines below the one a one-inverter roster actually reaches. So a family member
+# is reported WITH EVERY PLACE IT IS CALLED.
+def call_sites(name):
+    out = []
+    for path in sorted(APP.glob("*.py")):
+        tree = ast.parse(path.read_text())
+        for node in ast.walk(tree):
+            if not isinstance(node, ast.Call):
+                continue
+            if _called_name(node.func) != name:
+                continue
+            # ⚠️ THE RECEIVER IS PRINTED, because matching on the bare
+            # attribute name conflates methods: `evaluate` is the name of
+            # SAFETY-02's, SAFETY-18's and SAFETY-31's watchdogs alike, and
+            # a list of four lines with no receiver tells a reader nothing
+            # about which detector they are looking at. `inv.sign_wd` and
+            # `self.freeze_wd` are the disambiguation, and they are the
+            # caller's own words.
+            out.append(f"{path.name}:{node.lineno} `{ast.unparse(node.func)}`")
+    return out
+
+
+def lazy_log_sites():
+    """Log calls with a %-format template and >=2 substitution ARGUMENTS.
+
+    ⚠️ THE SIZE OF THE LARGEST HOLE, MEASURED RATHER THAN ASSERTED. The
+    NOT-SCANNED list below used to end "and app/ uses that form", which is a
+    claim about the tree with no number on it - the exact shape this card has
+    spent four rounds arguing against. `_LOG.error("%s ... %s", a, b)` puts both
+    operands in ARGUMENTS, so no f-string census here can ever reach them, and
+    transposing the two costs the same zero bytes. This counts them.
+    """
+    out = []
+    for path in sorted(APP.glob("*.py")):
+        tree = ast.parse(path.read_text())
+        for node in ast.walk(tree):
+            if not isinstance(node, ast.Call):
+                continue
+            if _called_name(node.func) not in _LOG_SINKS or len(node.args) < 3:
+                continue
+            head = node.args[0]
+            tmpl = ""
+            if isinstance(head, ast.Constant) and isinstance(head.value, str):
+                tmpl = head.value
+            elif isinstance(head, ast.BinOp) or isinstance(head, ast.JoinedStr):
+                tmpl = ast.unparse(head)
+            if tmpl.count("%") >= 2:
+                out.append((path.name, node.lineno,
+                            f"{path.name}:{node.lineno} "
+                            f"`{ast.unparse(node.func)}` with "
+                            f"{len(node.args) - 1} args"))
+    return [r[2] for r in sorted(out)]
+
+
+def _pair_line(sa, sb):
+    same = sa == sb
+    return (f"      format spec: '{sa}' / '{sb}'  -> "
+            + ("SAME - two values rendered alike, so a transposition is "
+               "SILENT and reads as a fact"
+               if same else
+               "DIFFERENT - likely mixed types, so a transposition is more "
+               "likely to look broken than to lie (gap 4 below)"))
+
+
+def main():
+    quiet = "--quiet" in sys.argv
+    rounds = build_fixpoint()
+    rows = scan()
+    fam = [r for r in rows if r["symmetric"] and "MESSAGE" in r["sinks"]
+           and "RETURN" not in r["sinks"]]
+    valued = [r for r in rows if r["symmetric"] and "RETURN" in r["sinks"]]
+    print("SYMMETRIC-PREDICATE FAMILY - argument order load-bearing for a "
+          "MESSAGE only")
+    print("=" * 78)
+    print(f"fixpoint reached after {rounds} round(s); "
+          f"{sum(len(v) for v in _SYM.values())} interchangeable positional "
+          f"and {sum(len(v) for v in _SYM_KW.values())} keyword pair(s) "
+          f"across {len(set(_SYM) | set(_SYM_KW))} function(s) in app/")
+    print(f"functions formatting >=2 of their own parameters into one "
+          f"sentence: {len(rows)} pair(s)")
+    print(f"of those, pairs whose SWAP LEAVES EVERY DECISION IDENTICAL: "
+          f"{len(fam) + len(valued)}")
+    print(f"  ...of which the sentence is RETURNED (so the swap is a VALUE "
+          f"change an ordinary check can see): {len(valued)}")
+    print(f"  ...and the sentence goes ONLY TO AN OPERATOR - THE FAMILY: "
+          f"{len(fam)}")
+    print()
+    print("THE FAMILY - a swap here is invisible to every behavioural check "
+          "BY CONSTRUCTION:")
+    for r in sorted(fam, key=lambda r: (r["module"], r["line"])):
+        kind = ("POSITIONAL - a transposition at a call site costs ZERO BYTES"
+                if r["positional"] else
+                "KEYWORD-ONLY at the definition - a transposition has to be "
+                "written out by name, which is not free and not silent")
+        print(f"  {r['module']}:{r['line']}  {r['func']}()   pair "
+              f"({r['a']}, {r['b']})")
+        print(f"      sentence at line(s): "
+              f"{', '.join(f'{l} -> {s}' for l, s in r['msg_lines'])}")
+        print(f"      {kind}")
+        sites = call_sites(r["func"])
+        print(f"      CALL SITES ({len(sites)}) - each one is a separate pin, "
+              f"and the receiver says which detector it is:")
+        for site in sites or ["(none inside app/)"]:
+            print(f"        {site}")
+    print()
+    print("SYMMETRIC, BUT THE SENTENCE IS THE RETURN VALUE - READ THIS BUCKET "
+          "BY HAND.")
+    print("A returned string is sometimes a KEY (a swap renames a store key or "
+          "an MQTT topic,")
+    print("which is behaviour every ordinary check can see - MAINT-05 is the "
+          "card about it)")
+    print("and sometimes a SENTENCE (a swap is message-only after all, and it "
+          "IS this family):")
+    for r in sorted(valued, key=lambda r: (r["module"], r["line"])):
+        print(f"  {r['module']}:{r['line']}  {r['func']}()   pair "
+              f"({r['a']}, {r['b']})")
+    print()
+    print("=" * 78)
+    print("CENSUS B - SENTENCES THE CALLER BUILDS, interpolating two values of "
+          "the SAME SHAPE")
+    print("A transposition inside one of these is ZERO BYTES and no predicate "
+          "is involved at")
+    print("all, so nothing behavioural can ever see it. Same rule: assert the "
+          "ORDERED PAIR.")
+    cb = scan_caller()
+    print(f"candidates: {len(cb)}")
+    for mod, line, fn, ua, ub, sa, sb in cb:
+        print(f"  {mod}:{line}  in {fn}()")
+        print(f"      {ua}   <->   {ub}")
+        print(_pair_line(sa, sb))
+    print()
+    print("=" * 78)
+    print("CENSUS C - SENTENCES AN OBJECT RETURNS ABOUT ITSELF  (SAFETY-38 "
+          "round 4)")
+    print("A method formatting its OWN ATTRIBUTES and RETURNING the string was "
+          "in neither")
+    print("census above: census A only reads a callee's PARAMETERS, census B "
+          "only scored a")
+    print("MESSAGE sink. The verdict below is resolved through the CALL SITES "
+          "of the")
+    print("returning method - a returned string is only in this family once "
+          "some caller")
+    print("hands it to an operator (contrast store.unit_key(), whose return "
+          "value is a KEY).")
+    cc = scan_returned()
+    fam_c = [r for r in cc if r["verdict"] == "MESSAGE"]
+    hot = [r for r in fam_c if r["spec_a"] == r["spec_b"]]
+    print(f"returned sentences with a same-shape pair: {len(cc)} pair(s); "
+          f"{len(fam_c)} reach an operator;")
+    print(f"of those, {len(hot)} ALSO share a format spec - two values "
+          f"rendered alike, which is")
+    print("the hazard gap 4 below names: a transposition there is silent and "
+          "reads as a fact.")
+    print()
+    print("*** = reaches an operator AND shares a format spec - THE ACTIONABLE "
+          "SUBSET")
+    print(" !  = reaches an operator, specs differ (a swap is likelier to look "
+          "broken)")
+    print("    = does not reach an operator, or could not be resolved")
+    # grouped by the sentence, so the CONSUMERS list is printed once per
+    # method rather than once per pair - the ungrouped form was 20 identical
+    # lines under each of six pairs and nobody reads that.
+    for key in sorted({(r["module"], r["line"], r["func"]) for r in cc}):
+        mod, line, fname = key
+        group = [r for r in cc if (r["module"], r["line"], r["func"]) == key]
+        v = group[0]["verdict"]
+        print(f"  {mod}:{line}  {fname}()   verdict: {v}")
+        for r in group:
+            mark = ("***" if r["verdict"] == "MESSAGE"
+                    and r["spec_a"] == r["spec_b"]
+                    else " ! " if r["verdict"] == "MESSAGE" else "   ")
+            print(f"    {mark} {r['a']}   <->   {r['b']}")
+            print(f"        {_pair_line(r['spec_a'], r['spec_b']).strip()}")
+        if not quiet:
+            sites = group[0]["sites"]
+            print(f"      CONSUMERS ({len(sites)}) - bare-name match, so read "
+                  f"the receiver:")
+            for label, sink, _v in sites or [("(none inside app/)", "", "")]:
+                print(f"        {label}  -> {sink}")
+    print()
+    print("=" * 78)
+    print("WHAT THIS SCANS, AND WHAT IT DOES NOT - stated because round 4's "
+          "blocker was")
+    print("a completeness this file ASSERTED and did not have. The sink "
+          "classifier is a")
+    print("syntactic walk up the parent chain plus ONE step of local data "
+          "flow, and it")
+    print("recognises exactly these sinks and no others:")
+    print(f"  SCANNED as a MESSAGE : a call to {sorted(_LOG_SINKS)}")
+    print("                         ...or to `append`; a `raise`; an "
+          "assignment to an")
+    print(f"                         attribute or local named {sorted(_MSG_ATTRS)}")
+    print("                         ...or to a local that is then interpolated "
+          "into one of")
+    print("                         those (the one data-flow step).")
+    print("  SCANNED as a RETURN  : census C - resolved through the returning "
+          "method's")
+    print("                         call sites, one hop plus two of recursion.")
+    print("  NOT SCANNED AT ALL, and each of these can hold a member:")
+    lazy = lazy_log_sites()
+    print("    * `%s`-style lazy logging - `_LOG.error('%s ... %s', a, b)`. The "
+          "arguments")
+    print("      are not an f-string, so no census here looks at them, and a "
+          "transposition")
+    print("      of two `%s` arguments is the same zero-byte edit. THIS IS THE "
+          "LARGEST")
+    print(f"      REMAINING HOLE, and it is MEASURED, not asserted: "
+          f"{len(lazy)} such call(s)")
+    print(f"      in app/, across "
+          f"{len({s.split(':')[0] for s in lazy})} module(s). None of them is "
+          f"scanned by anything")
+    print("      above. Listed here so the size of the hole is a number:")
+    for site in lazy or ["(none)"]:
+        print(f"        {site}")
+    print("    * `.format()`, `%`-formatting, and sentences built by `+` or "
+          "`.join()` out of")
+    print("      non-f-string pieces.")
+    print("    * A sentence that leaves the function inside a DICT, LIST or "
+          "dataclass and is")
+    print("      rendered somewhere else - the one data-flow step is local and "
+          "follows only")
+    print("      a bare Name.")
+    print("    * `yield`ed sentences, and sentences stored on an object by any "
+          "attribute")
+    print(f"      name outside {sorted(_MSG_ATTRS)}.")
+    print("    * Anything outside `app/`: `sim/`, `tools/`, `web.py`'s "
+          "templates, the")
+    print("      translations JSON, the firmware, the witness.")
+    print()
+    print("WHAT IT CAN SEE BUT GETS WRONG - the shape of each gap, named "
+          "rather than")
+    print("rounded off:")
+    print("  1. SEMANTIC symmetry no canonicaliser above spells. The list of "
+          "commutative")
+    print("     forms is finite and hand-written; a function symmetric only "
+          "through a form")
+    print("     not on it is REJECTED and never appears. This under-reports.")
+    print("  2. In CENSUS B and C, two interpolated values of the same KIND "
+          "that are not the")
+    print("     same SHAPE - `a.lo` beside `hi`, or one of them behind a local "
+          "variable.")
+    print("     Only one-leaf-apart expressions are paired.")
+    print("  3. WHETHER each call site is pinned. The sites are listed above; "
+          "whether a")
+    print("     check asserts the ORDERED PAIR at each one is a fact about "
+          "`test_*.py` and is")
+    print("     recorded in DECISIONS/SAFETY-38-site-standing-pin.md section "
+          "7. Call sites")
+    print("     outside `app/` are not listed either, and every site list here "
+          "matches on the")
+    print("     bare METHOD NAME - three watchdogs are all called `evaluate` "
+          "and at least")
+    print("     four unrelated classes have an `explain()` - so the receiver is "
+          "printed")
+    print("     beside each one and a reader has to pick.")
+    print("  4. ⚠️ IT CAN ALSO OVER-REPORT, IN ONE EXACT WAY. The sentence is "
+          "ERASED before")
+    print("     census A's comparison, so a swap that would make the FORMATTING "
+          "ITSELF fail")
+    print("     - a `DAY_NAMES[start]` where `start` is 1320 - is scored as "
+          "'changes no")
+    print("     decision'. `_raise_gap`'s (start, weekday) pairs are that. The "
+          "hazard is a")
+    print("     SAME-TYPED pair, which is why every census B and C row now "
+          "prints whether")
+    print("     the two format specs match.")
+    print("  5. CENSUS C's verdict is a bare-name resolution (gap 3) and "
+          "therefore reads")
+    print("     MESSAGE too readily. Every verdict is printed with the sites "
+          "that produced")
+    print("     it; a MESSAGE verdict is a prompt to read them, not a proof.")
+
+
+if __name__ == "__main__":
+    main()

goodwe_controller/tools/translations_lint.py

@@ -0,0 +1,238 @@
+"""UX-01: read config.yaml's option surface and the translations, and compare.
+
+⚠️ WHY THIS IS A MODULE AND NOT A FUNCTION INSIDE THE CHECK. Two very different
+programs have to agree about what is in `translations/*.yaml`:
+
+  * `test_translations.py`, which runs in the add-on's own CI image - Alpine,
+    python3 + py3-aiohttp + py3-paho-mqtt and NOTHING ELSE. There is no PyYAML
+    there and a check that skips on ImportError is not a check, so the parser
+    below is written by hand;
+  * `tools/supervisor_shape_probe.py`, which runs inside the real Home Assistant
+    Supervisor image and loads the same files with the loader Home Assistant
+    ACTUALLY uses (`supervisor.utils.yaml.read_json_or_yaml_file`, validated by
+    `SCHEMA_APP_TRANSLATIONS`).
+
+A hand parser that quietly disagrees with the real loader is precisely the
+defect this repository keeps finding - a check whose data cannot reach the
+failure it names. So the probe imports THIS module and asserts, key by key and
+string by string, that `parse_translation_file()` and the real loader return the
+same thing. That equality is the licence for CI to use the hand parser at all.
+
+The parser is DELIBERATELY STRICT. It accepts exactly the shape UX-01 generates
+- two-space indentation, one `key:` mapping opener or one `key: "double quoted
+scalar"` per line, `#` comments, blank lines - and RAISES on anything else. A
+permissive parser would answer "no problems" for a file it had silently skipped
+half of, which is the same failure wearing a passing grade.
+"""
+
+import io
+import re
+
+__all__ = ["parse_translation_file", "parse_translation_text", "config_surface",
+           "audit"]
+
+
+class TranslationSyntaxError(ValueError):
+    """The file is not in the subset this parser accepts. Never silently skip."""
+
+
+_LINE = re.compile(r"^(?P<indent> *)(?P<name>[A-Za-z0-9_.:/-]+):(?P<rest>.*)$")
+
+
+def _unescape(raw, lineno):
+    """The body of a YAML double-quoted scalar -> its value."""
+    out, i = [], 0
+    while i < len(raw):
+        ch = raw[i]
+        if ch == "\\":
+            if i + 1 >= len(raw):
+                raise TranslationSyntaxError(f"line {lineno}: trailing backslash")
+            nxt = raw[i + 1]
+            if nxt not in ('"', "\\"):
+                # Deliberately narrow: UX-01's generator emits only these two.
+                # Anything else is a shape this parser has not been measured on.
+                raise TranslationSyntaxError(
+                    f"line {lineno}: unsupported escape \\{nxt}")
+            out.append(nxt)
+            i += 2
+            continue
+        if ch == '"':
+            raise TranslationSyntaxError(f"line {lineno}: unescaped quote")
+        out.append(ch)
+        i += 1
+    return "".join(out)
+
+
+def parse_translation_text(text, where="<text>"):
+    """A nested dict from the strict two-space YAML subset UX-01 writes.
+
+    Raises TranslationSyntaxError on ANY line it does not fully understand.
+    """
+    root = {}
+    stack = [(-2, root)]                      # (indent, mapping)
+    for lineno, line in enumerate(text.splitlines(), 1):
+        if not line.strip() or line.lstrip().startswith("#"):
+            continue
+        if line.rstrip() != line:
+            raise TranslationSyntaxError(f"{where} line {lineno}: trailing whitespace")
+        m = _LINE.match(line)
+        if not m:
+            raise TranslationSyntaxError(f"{where} line {lineno}: not `key:` -> {line!r}")
+        indent, name, rest = len(m.group("indent")), m.group("name"), m.group("rest")
+        if indent % 2:
+            raise TranslationSyntaxError(
+                f"{where} line {lineno}: indent {indent} is not a multiple of 2")
+        while stack and indent <= stack[-1][0]:
+            stack.pop()
+        if not stack:
+            raise TranslationSyntaxError(f"{where} line {lineno}: dedented past the root")
+        parent_indent, parent = stack[-1]
+        if indent != parent_indent + 2:
+            raise TranslationSyntaxError(
+                f"{where} line {lineno}: indent {indent} does not open under "
+                f"indent {parent_indent}")
+        if name in parent:
+            raise TranslationSyntaxError(f"{where} line {lineno}: duplicate key {name!r}")
+        if rest == "":
+            child = {}
+            parent[name] = child
+            stack.append((indent, child))
+            continue
+        if not rest.startswith(" "):
+            raise TranslationSyntaxError(f"{where} line {lineno}: no space after the colon")
+        value = rest[1:]
+        if len(value) < 2 or value[0] != '"' or value[-1] != '"':
+            raise TranslationSyntaxError(
+                f"{where} line {lineno}: scalars must be double quoted -> {value!r}")
+        parent[name] = _unescape(value[1:-1], lineno)
+    return root
+
+
+def parse_translation_file(path):
+    return parse_translation_text(io.open(path, encoding="utf-8").read(), str(path))
+
+
+# --- config.yaml's option surface --------------------------------------------
+# ⚠️ THE SCHEMA HALF, NOT THE OPTIONS HALF, AND THAT IS A MEASUREMENT RATHER
+# THAN A PREFERENCE. Supervisor's `App.schema_ui` is `UiOptions(...)(data[
+# ATTR_SCHEMA])`, so the ORDER the Configuration tab renders in is the order of
+# the `schema:` block and nothing else. tools/supervisor_shape_probe.py section
+# F prints that order out of the real image.
+#
+# ⚠️ ANCHORED ON THE INDENTATION, never on a stripped line. A top-level schema
+# key is at EXACTLY two spaces and everything nested is at four or more; the
+# `max_w` inside `inverters:` and the flat `max_w` are the same text otherwise,
+# and config.yaml declares the nested one FIRST on purpose so that a first-match
+# stripped reader is caught. See test_inverter.py part 12.
+_TOP = re.compile(r"^  ([a-z_0-9]+):(.*)$")
+_NESTED = re.compile(r"^ {4,}(?:- )?([a-z_0-9]+): *(\S.*?) *$")
+
+
+def config_surface(config_text):
+    """(top-level schema keys in render order, {key: [nested per-entry keys]}).
+
+    Nested keys are the ones a list-of-objects option declares per entry - today
+    only `inverters:`. A list of scalars (`- str`) declares none, and comes back
+    absent from the second dict rather than as an empty list.
+    """
+    marker = config_text.index("\nschema:")
+    half = config_text[marker:]
+    order, nested, current = [], {}, None
+    for line in half.splitlines():
+        m = _TOP.match(line)
+        if m:
+            order.append(m.group(1))
+            current = m.group(1) if not m.group(2).strip() else None
+            continue
+        stripped = line.strip()
+        if not stripped or stripped.startswith("#"):
+            continue
+        if current is None:
+            continue
+        n = _NESTED.match(line)
+        if n:
+            nested.setdefault(current, []).append(n.group(1))
+        else:
+            current = None
+    if len(order) != len(set(order)):
+        dupes = sorted({k for k in order if order.count(k) > 1})
+        raise ValueError(f"config.yaml declares {dupes} twice at the top level of schema:")
+    return order, nested
+
+
+# --- the audit ---------------------------------------------------------------
+def audit(config_text, translation, lang, require_descriptions=True):
+    """Every disagreement between config.yaml and one translation file.
+
+    Returns a list of strings. EMPTY MEANS AGREEMENT; each string names the key
+    and says which direction the disagreement runs, because "the translations do
+    not match" is not something anybody can act on.
+    """
+    order, nested = config_surface(config_text)
+    problems = []
+    top = translation.get("configuration")
+    if not isinstance(top, dict):
+        return [f"{lang}: no `configuration:` block at all"]
+    # ⚠️ THE WHOLE FILE IS ALL-OR-NOTHING, AND THAT IS WHY THESE TWO LINES ARE
+    # HERE RATHER THAN ONLY THE `configuration:` COVERAGE BELOW.
+    # `_read_app_translations()` runs the file through SCHEMA_APP_TRANSLATIONS
+    # and, on `vol.Invalid`, LOGS A WARNING AND DROPS THE WHOLE FILE - every
+    # label in it, not just the offending key. So a shape Supervisor refuses is
+    # not a small defect that costs one description; it silently returns the tab
+    # to raw keys. The two ways to write one that this parser can still read are
+    # a top-level block that is not `configuration` or `network`, and a
+    # `network:` block whose values are not strings ({str: str} is the schema).
+    for extra in sorted(set(translation) - {"configuration", "network"}):
+        problems.append(f"{lang}: `{extra}:` is not a block Supervisor reads "
+                        "(only `configuration` and `network` are) - "
+                        "SCHEMA_APP_TRANSLATIONS refuses the file and the "
+                        "Supervisor DROPS ALL OF IT with a log warning")
+    for port, text in sorted((translation.get("network") or {}).items()):
+        if not isinstance(text, str):
+            problems.append(f"{lang}: `network.{port}` is not a string - "
+                            "`network:` is {str: str} and a mapping there makes "
+                            "Supervisor drop the WHOLE file, every label in it")
+
+    for key in order:
+        entry = top.get(key)
+        if entry is None:
+            problems.append(f"{lang}: option `{key}` has no translation - Home "
+                            "Assistant would render the raw key")
+            continue
+        if not isinstance(entry, dict):
+            problems.append(f"{lang}: `{key}` is not a mapping")
+            continue
+        if not str(entry.get("name", "")).strip():
+            problems.append(f"{lang}: option `{key}` has no `name`")
+        if require_descriptions and not str(entry.get("description", "")).strip():
+            problems.append(f"{lang}: option `{key}` has no `description` - the "
+                            "operator gets a label and no way to know whether to "
+                            "touch it")
+        want = nested.get(key, [])
+        got = entry.get("fields")
+        if want and not isinstance(got, dict):
+            problems.append(f"{lang}: `{key}` is a repeatable section with "
+                            f"per-entry keys {sorted(want)} and no `fields:` block")
+            continue
+        if got is not None and not want:
+            problems.append(f"{lang}: `{key}` carries a `fields:` block but "
+                            "config.yaml declares no per-entry keys for it")
+            continue
+        for sub in want:
+            se = (got or {}).get(sub)
+            if se is None:
+                problems.append(f"{lang}: `{key}` per-entry key `{sub}` has no "
+                                "translation")
+                continue
+            if not str(se.get("name", "")).strip():
+                problems.append(f"{lang}: `{key}.{sub}` has no `name`")
+            if require_descriptions and not str(se.get("description", "")).strip():
+                problems.append(f"{lang}: `{key}.{sub}` has no `description`")
+        for orphan in sorted(set(got or {}) - set(want)):
+            problems.append(f"{lang}: `{key}.{orphan}` is translated but "
+                            "config.yaml declares no such per-entry key")
+
+    for orphan in sorted(set(top) - set(order)):
+        problems.append(f"{lang}: `{orphan}` is translated but config.yaml "
+                        "declares no such option - a rename or a typo")
+    return problems

goodwe_controller/translations/en.yaml

@@ -0,0 +1,275 @@
+# Home Assistant add-on translations - ENGLISH (UX-01)
+#
+# ⚠️ WHAT THIS FILE IS FOR, AND WHAT HOME ASSISTANT ACTUALLY DOES WITH IT.
+# Without a `translations/` directory the Configuration tab renders the raw
+# option KEYS - `unit_sign_disagree_w`, `saturation_cycles`, `integrator_max_w`.
+# The frontend keeps a field when `e.name in options || e.required`, and all 70
+# keys are in `options:` (59 of them are `required` as well), so ALL SEVENTY are
+# rendered, always, in `schema:` order, with no description. This file is what
+# turns that into sentences.
+#
+# HOW IT IS READ, measured on the Supervisor image this site runs
+# (ghcr.io/home-assistant/amd64-hassio-supervisor:2026.08.0):
+#
+#   * `supervisor/store/data.py:_read_app_translations()` reads every
+#     `.yaml`/`.yml`/`.json` in this directory, keyed by FILE STEM (so this file
+#     is the `en` translation), and validates each through
+#     `SCHEMA_APP_TRANSLATIONS`: `configuration: {str: {name (required),
+#     description, fields}}` plus `network: {str: str}`. ⚠️ A FILE THAT FAILS
+#     THAT SCHEMA IS DROPPED WITH A LOG WARNING AND NOTHING ELSE - the add-on
+#     goes on rendering raw keys and nobody is told twice. tools/
+#     supervisor_shape_probe.py section F is what says it loaded.
+#   * The frontend resolves each label as
+#     `translations[<user's language>]?...name || translations["en"]?...name ||
+#     schema.name`, and the helper text the same way with `description`. ⚠️ THE
+#     FALLBACK IS PER KEY, so a key missing from nl.yaml degrades to this file,
+#     while a key present but wrong does not degrade at all.
+#
+# ⚠️ ORDER IS NOT SET HERE. `App.schema_ui` is `UiOptions(...)(data["schema"])`,
+# so the Configuration tab renders in the order of config.yaml's `schema:`
+# block. The order below only mirrors it so the two files read alike.
+#
+# ⚠️ ADD-ON OPTIONS ARE A FLAT LIST. There is no section-header primitive, no
+# per-option "advanced" flag, no units on the input and no sliders, so grouping
+# is approximated by ORDER plus the `Group · ` prefix in each label. Do not
+# promise the operator visual sections; there are none.
+#
+# ⚠️ EVERY DERIVED CONSTANT SAYS WHERE IT CAME FROM. The Configuration tab
+# presents a number read off 1890 closed-loop test runs and the operator's own
+# inverter rating as the same kind of field. The descriptions are the only place
+# that difference can be stated, so a derived value names its campaign and says
+# "do not change without re-deriving", and a value that is genuinely the
+# operator's says so too.
+configuration:
+  setpoint_entity:
+    name: "Hardware · Inverter setpoint entity"
+    description: "The ESPHome number entity this add-on writes the power setpoint to, normally number.*_goodwe_setpoint_w. This is the only thing the add-on commands. Leave it empty if you fill in the inverter list below: a site with a roster must not also name one loose actuator, and the add-on refuses to start when both are set."
+  soc_entity:
+    name: "Hardware · Battery charge level entity (%)"
+    description: "The sensor that reports the pack's state of charge in percent. Use the ESP32's own reading, not a figure computed somewhere else. The maintenance cycle and every charge-level floor read this."
+  batt_entity:
+    name: "Hardware · Battery power entity (W)"
+    description: "The sensor that reports this inverter's own battery power, positive while discharging. On this installation that is holding register 0x0518, read by the ESP32. The sign watchdog and the circulating-power alarm both grade the inverter against this reading."
+  batt_invert:
+    name: "Hardware · Battery power sign is reversed"
+    description: "Only switch this on if your battery power sensor reports discharging as a negative number. The add-on expects positive to mean discharging."
+  inverters:
+    name: "Hardware · Inverter list (leave empty if you have one inverter)"
+    description: "Leave this empty unless the site really has more than one inverter. EMPTY DOES NOT MEAN 'not configured yet': it means the four entity settings above, together with the inverter rating and the battery cut-out under Limits, describe the one inverter you have. That is what every existing installation reads, and nobody has to touch anything. Filling this in REPLACES those settings instead of extending them, and nothing is inherited: each entry has to name its own actuator, its own rating and its own battery cut-out, so that no inverter is ever judged against another unit's numbers. The flat setpoint entity above must then be left empty."
+    fields:
+      name:
+        name: "Name"
+        description: "A short identifier for this inverter, for example inverter-a. It gives this unit its own namespace for its safety latch, heartbeat and write bookkeeping in the add-on's state file, so two units may not share one."
+      setpoint_entity:
+        name: "Setpoint entity"
+        description: "This inverter's own ESPHome number.*_goodwe_setpoint_w. Two entries may not name the same one - two writers on one actuator is refused at startup."
+      max_w:
+        name: "Inverter rating (W)"
+        description: "The supervised ceiling on what may be written to THIS inverter; the site's ceiling is the sum over the list. Required of every entry: an entry without one would have to borrow a rating, and judging one inverter against another unit's numbers is exactly the fault this per-entry list exists to remove."
+      bms_soc_floor:
+        name: "Battery cut-out level (%)"
+        description: "The percent at which THIS pack's own battery management system cuts out. Read it off the pack that is actually installed (register 0x0560) before that pack is ever commanded; do not copy another unit's figure. Required of every entry, deliberately: an optional one would be a defaulted one, and one default for two batteries of different models protects the shallower pack with the deeper pack's number."
+      soc_entity:
+        name: "Battery charge level entity (%) (optional)"
+        description: "This pack's own state of charge. Leave it empty if this unit reports none - that is what it means, and it never falls back to another unit's sensor."
+      batt_entity:
+        name: "Battery power entity (W) (optional)"
+        description: "This unit's own battery power, positive while discharging. Leave it empty if this unit reports none; nothing is inherited from another entry."
+      batt_invert:
+        name: "Battery power sign is reversed (optional)"
+        description: "Only for this entry: switch it on if this unit's battery power sensor reports discharging as a negative number."
+  estop_fitted:
+    name: "Hardware · RS485 emergency stop is fitted"
+    description: "Whether the RS485 emergency stop is physically installed. It only drives the warning banner on the status page; it changes no control behaviour."
+  meter_source:
+    name: "Meter · Where the meter reading comes from"
+    description: "'off' keeps the single Home Assistant entity below, which is what an existing installation runs on until you choose otherwise. ha_dsmr subscribes to the DSMR integration; mqtt_p1 reads an MQTT topic; ha_signed reads one signed entity, which is what a HomeWizard P1 publishes; homewizard_local polls the meter's own local API and skips Home Assistant entirely. ⚠️ Only homewizard_local can tell 'the meter has not answered' apart from 'the value has not changed', so it is the only source on which the frozen-meter alarm means anything."
+  meter_entity:
+    name: "Meter · Grid power entity (W)"
+    description: "The net grid power sensor, used when the meter source is 'off'. POSITIVE MUST MEAN DRAWING FROM THE GRID. Get this the wrong way round and the loop drives the battery in the wrong direction; use the sign switch below rather than a template sensor."
+  meter_invert:
+    name: "Meter · Grid power sign is reversed"
+    description: "Switch this on if your grid sensor reports drawing from the grid as a negative number."
+  meter_phases:
+    name: "Meter · Number of phases (1 or 3)"
+    description: "Must match your connection. A telegram whose phase count disagrees is rejected as it arrives and logged, so a wrong value shows up straight away as 'no telegrams accepted' rather than as a quietly wrong number. The range accepts 2, but that is not a real Belgian connection."
+  p1_host:
+    name: "Meter · HomeWizard P1 address"
+    description: "For meter source homewizard_local only: the meter's own address on your network, as host or host:port, for example 192.168.2.250."
+  meter_poll_s:
+    name: "Meter · Seconds between meter polls"
+    description: "For meter source homewizard_local only. 5 s is the meter's own update rate, so there is nothing to gain below it. It must stay well under the staleness limit below - the reading is never fresher than this interval - and the add-on refuses to start if it is at or above that limit."
+  meter_max_age_s:
+    name: "Meter · A reading counts as stale after (s)"
+    description: "Beyond this the grid figure counts as missing. On its own it does not command 0 W: the 'inputs missing' timer under Advanced starts only after this one has expired, and the two stack. 30 s is six polls of headroom at the default poll interval."
+  meter_mqtt_topic:
+    name: "Meter · MQTT topic"
+    description: "For meter source mqtt_p1 only: the topic the P1 readings are published on."
+  p1_import_entity:
+    name: "Meter · Import register entity (W)"
+    description: "The UNSIGNED consumption register. Do not point this at a signed template sensor: the add-on works out net power itself as import minus export, so the sign convention lives in tested code rather than in unreviewed YAML."
+  p1_export_entity:
+    name: "Meter · Export register entity (W)"
+    description: "The UNSIGNED injection register, the counterpart of the import register above. Same rule: no signed template sensor."
+  p1_net_entity:
+    name: "Meter · Signed net power entity (W)"
+    description: "For meter source ha_signed only. ONE signed sensor: positive is drawn from the grid, negative is fed back into it. Do not split it into two template sensors - the add-on does that split itself, so that it is tested."
+  p1_phase_import_entities:
+    name: "Meter · Per-phase import entities (L1, L2, L3)"
+    description: "Optional, in L1..L3 order. Needed for the capacity-tariff quarter-hour peak on a three-phase connection. The number of entries must equal the number of phases above."
+  p1_phase_export_entities:
+    name: "Meter · Per-phase export entities (L1, L2, L3)"
+    description: "Optional, in L1..L3 order, alongside the per-phase import entities above. The number of entries must equal the number of phases."
+  p1_phase_net_entities:
+    name: "Meter · Per-phase signed net entities (L1, L2, L3)"
+    description: "For meter source ha_signed only. Optional, in L1..L3 order, each signed the same way as the net entity above. Same job as the per-phase import and export entities: the capacity-tariff quarter-hour peak on a three-phase connection. The number of entries must equal the number of phases."
+  max_w:
+    name: "Limits · Inverter rating (W)"
+    description: "THIS IS YOUR NUMBER, not a derived one: the hard ceiling on what may ever be commanded, in watts. Set it to what your inverter is actually rated for, start low and raise it once the site has been commissioned. It is not read at all when the inverter list is filled in - each entry then carries its own, and the site ceiling is their sum. Several safety thresholds must stay below it, and the add-on refuses to start if one does not."
+  bms_soc_floor:
+    name: "Limits · Battery cut-out level (%)"
+    description: "MEASURED, not chosen: the percent at which the pack's OWN battery management system stops discharging, whatever this add-on is set to. Register 0x0560 reads 10 on the reference GW5000S-BP. Read it off the pack you actually have rather than copying this figure. It is here so the add-on can refuse a capacity-guard floor at or below it: such a floor could never bind, the BMS would win first, and the status page would report an energy backstop that does not exist. Not read when the inverter list is filled in - each entry then states its own pack's cut-out."
+  peak_cap_w:
+    name: "Limits · Capacity-tariff target (W)"
+    description: "THIS IS YOUR NUMBER: the quarter-hour average demand the peak guard tries to stay under. Take it from your grid contract - in Belgium it is the capacity-tariff peak your distribution charge is billed on."
+  peak_forecast_entity:
+    name: "Limits · Quarter-hour demand forecast entity (W)"
+    description: "Optional. A forecast of the current billing quarter's average demand. Leave it empty and there is no capacity cap at all."
+  peak_soc_floor:
+    name: "Limits · Peak guard will not discharge below (%)"
+    description: "DERIVED, not picked (SAFETY-24): the reference pack holds 13.8 kWh usable and the worst modelled peak-shaving day asks for 878 Wh, which is 6.4 %, so 20 % sits ten points above the pack's own cut-out and still leaves the guard about 1.6 of its worst observed days of room. ⚠️ IT BOUNDS THE PEAK GUARD ONLY. It is not a reserve for the whole pack: ordinary self-consumption discharges straight past it and goes on down to the battery cut-out, and raising this number does not change that by a tenth of a percent. It must stay strictly above the battery cut-out or the add-on refuses to start. Do not change it without re-deriving it."
+  price_provider:
+    name: "Tariff · Dynamic price source"
+    description: "Where day-ahead or real-time prices come from. 'off' is what ships, and means this site runs on the static tariff below with no trading. ⚠️ Switching it on today fetches, checks and publishes prices and changes no energy decision - nothing consumes the price series yet. It may not be combined with the two legacy Home Assistant price entities further down: two price sources on one site, one of which silently wins, is refused at startup rather than left looking armed."
+  price_markup_eur_kwh:
+    name: "Tariff · Supplier markup (EUR/kWh)"
+    description: "Your supplier's margin. The add-on adds it ONLY when the chosen price source does not already include it - under engie_dynamic, totalenergies_dynamic, eneco_eddy and manual_csv it is ignored, and logged as ignored, never applied twice."
+  price_taxes_eur_kwh:
+    name: "Tariff · Levies and VAT (EUR/kWh)"
+    description: "Taxes and levies per kWh, added under the same rule as the supplier markup: only when the chosen price source does not already carry them."
+  export_price_eur_kwh:
+    name: "Tariff · Injection price (EUR/kWh)"
+    description: "What you are paid for feeding a kWh back into the grid, all in. One number rather than a series: no supplier here publishes a dynamic injection curve. In Belgium it is often close to zero, which on its own strongly favours using your own production over exporting it. It may be negative - at midday in summer you can be paying to export."
+  static_profile:
+    name: "Tariff · Fixed or day/night tariff (one line of JSON)"
+    description: "Your fixed or day/night contract, written as a single line of JSON. RECOMMENDED EVEN ON A DYNAMIC CONTRACT: this is what the add-on falls back to when the price feed dies, and with it empty a dead feed leaves the site with no tariff at all. The periods must cover every day type exactly once, with no gap and no overlap - a gap is refused at startup rather than filled in, because an invented price is one a strategy would trade on. A fully fixed tariff is one period covering 00:00-24:00 on all days. Prices are ALL IN; the markup and levies above are not added to them. Note that a window written 22:00-07:00 for mon-fri does NOT cover Saturday morning, so a weekend row is required rather than decorative."
+  price_csv_path:
+    name: "Tariff · Price CSV file"
+    description: "For price source manual_csv only: where in /share the add-on reads your own price file from."
+  price_feed_url:
+    name: "Tariff · Price feed URL override"
+    description: "Leave empty to use the chosen source's own feed. Only a host that source itself declares is accepted, so this cannot be pointed anywhere."
+  price_horizon_h:
+    name: "Tariff · How far ahead to fetch prices (hours)"
+    description: "How many hours of prices to ask the source for."
+  price_timeout_s:
+    name: "Tariff · Price request timeout (s)"
+    description: "How long a single request to the price source may take before it is given up on."
+  price_now_entity:
+    name: "Tariff · Current price entity (older price path)"
+    description: "The older way of getting a price, kept because retiring it would take the maintenance cycle's only price signal away from a live installation. The add-on reads this and the average below and derives exactly one thing from them - whether now is cheaper than average - which only the maintenance cycle's cheap-window charging uses. It may not be combined with a dynamic price source."
+  price_avg_entity:
+    name: "Tariff · Average price entity (older price path)"
+    description: "The average the current price is compared against. Only meaningful together with the current-price entity above, and like it, may not be combined with a dynamic price source."
+  arbitrage_enabled:
+    name: "Tariff · Trade on the price spread"
+    description: "Charge in the cheapest published hour and discharge in the dearest, but only when the spread covers what the round trip costs. OFF in the shipped configuration, deliberately: this is the first strategy in the add-on that moves energy against the meter on purpose, so it is armed on purpose or not at all. It needs both a price source and a P1 meter, and the add-on refuses the combinations that cannot work rather than letting them look armed."
+  cycle_cost_threshold_eur:
+    name: "Tariff · Cost of one full charge/discharge cycle (EUR/kWh)"
+    description: "What one full round trip costs per kWh: wear on the pack plus conversion losses. A price spread smaller than this loses money and battery life, so it is not traded. ⚠️ THIS ONE IS NOT DERIVED FROM A MEASUREMENT. 0.10 is a product decision and it is still an open question with the owner (OPT-08). At this value a fixed day/night site does not trade at all - the realistic Belgian day/night spread is about 0.08 EUR/kWh - and that is the correct verdict at this number, not a fault."
+  arbitrage_soc_floor:
+    name: "Tariff · Trading may not discharge below (%)"
+    description: "The reserve price trading may not spend. Deliberately not the same key as the maintenance floor: pointing a trading strategy at the monthly balancing cycle's numbers would couple two unrelated policies through one setting."
+  arbitrage_soc_ceiling:
+    name: "Tariff · Trading may not charge above (%)"
+    description: "The headroom price trading may not fill. The counterpart of the trading floor above, and kept separate from the maintenance target for the same reason."
+  maintenance_enabled:
+    name: "Maintenance · Run the monthly battery cycle"
+    description: "A deliberate deep discharge followed by a full recharge and a hold, so the battery management system can recalibrate its charge estimate and balance the cells. Off by default."
+  maintenance_interval_days:
+    name: "Maintenance · Minimum days between cycles"
+    description: "The shortest gap between two maintenance cycles."
+  maintenance_start_hour:
+    name: "Maintenance · Hour of day a due cycle starts"
+    description: "Local hour, 0 to 23, at which a cycle that has become due begins."
+  maintenance_discharge_w:
+    name: "Maintenance · Discharge rate (W)"
+    description: "How fast the cycle drains the pack; the surplus is exported. Above the inverter rating it is CLAMPED to the rating rather than refused - the cycle still completes, just more slowly, and the status page says so. It ships at 2000 to match the shipped rating; raise the rating first, then this."
+  maintenance_charge_w:
+    name: "Maintenance · Recharge rate (W)"
+    description: "⚠️ MUST STAY AT OR BELOW the inverter rating, and the add-on refuses to start otherwise. Above it, the cheap-window charge shaping asks for more than the supervised limit allows, the arbiter resolves that contradiction to 0 W, and maintenance would silently never charge in a cheap window on a default installation. It is also capped again by whatever headroom the peak guard leaves."
+  maintenance_soc_floor:
+    name: "Maintenance · Discharge down to (%)"
+    description: "The depth the monthly recalibration deliberately goes to, once a month, on purpose. ⚠️ THIS IS NOT THE PEAK GUARD'S FLOOR: that one is the depth a money-saving discharge may never reach on any day. The right values genuinely differ - 11 here against 20 there - which is why they are two separate settings and must not be merged."
+  maintenance_soc_target:
+    name: "Maintenance · Recharge up to (%)"
+    description: "The level the recharge phase aims for before the hold begins."
+  maintenance_hold_min:
+    name: "Maintenance · Hold at full for (minutes)"
+    description: "How long to sit at the target so the battery management system can finish balancing the cells."
+  sign_disagree_w:
+    name: "Safety · Sign watchdog threshold (W) — measured, do not change"
+    description: "MEASURED, NOT CHOSEN (SAFETY-02). Both the setpoint being emitted and the grid reading must exceed this before their opposite signs count as a disagreement at all. On the captured healthy day (2026-08-23) sign agreement over the gated samples is 93.4 %; on the captured fault day (2026-08-20) the clusters run 0.0-10.5 % with opposed runs up to 1752 s. There is no reason to move this without a new capture that says so. It must stay below the inverter rating or the watchdog can never fire, and the add-on refuses that configuration."
+  sign_disagree_s:
+    name: "Safety · Sign watchdog hold (s) — measured, do not change"
+    description: "MEASURED, NOT CHOSEN (SAFETY-02). How long the setpoint and the meter must stay opposed, continuously, before the add-on commands 0 W and latches until an operator starts control again. 180 s sits in the middle of a very wide measured gap: the longest legitimate opposed run on the healthy day is 30 s, while the fault day still trips 13 times at 300 s. Do not change it without a new capture."
+  unit_sign_disagree_w:
+    name: "Safety · Per-inverter sign threshold (W) — derived, do not change"
+    description: "TWO OR MORE INVERTERS ONLY; with one inverter this setting does nothing at all. DERIVED FROM 1890 CLOSED-LOOP TEST RUNS on the two-master rig (SAFETY-30), in which nothing was faulty, swept across the whole range this add-on accepts for loop gain and slew rate. 250 W is exactly half the saturation threshold, so the smallest divergence this can see is precisely the gap at which the control law itself already says the inverter is not following. Do not change it without re-deriving it. It must stay below the inverter rating or it can never fire."
+  unit_sign_disagree_s:
+    name: "Safety · Per-inverter sign hold (s) — derived, do not change"
+    description: "TWO OR MORE INVERTERS ONLY. DERIVED FROM 1890 CLOSED-LOOP TEST RUNS (SAFETY-30): 85 s is 8.5 times the worst legitimate opposition those runs produce (10.0 s), 2.8 times the firmware's own 30 s link veto, and under half the 180 s the site-wide check takes. Do not change it without re-deriving it."
+  site_sign_disagree_w:
+    name: "Safety · Site-wide sign threshold (W) — measured, do not change"
+    description: "TWO OR MORE INVERTERS ONLY. The same 300 W as the single-inverter threshold, CARRIED ACROSS DELIBERATELY (SAFETY-30): the argument behind it does not depend on how many inverters there are - near zero the sign is noise, the deadband is 15 W, and there is one meter whatever is behind it. Do not change it without a capture that says so."
+  site_sign_disagree_s:
+    name: "Safety · Site-wide sign hold (s) — derived, do not change"
+    description: "TWO OR MORE INVERTERS ONLY. DERIVED FROM 1890 CLOSED-LOOP TEST RUNS (SAFETY-30), and deliberately NOT carried across from the single-inverter 180 s. On those runs the worst legitimate opposition at 300 W is 110 s with one inverter and 215 s with two, because the command has to travel the whole site rail at a slew rate that is not the site's - so carrying 180 s across would have shipped a false trip reachable at the lowest gain and slew with an ordinary 2.2 kW load reversal. 325 s is 1.51 times that, still inside the 900 s billing quarter, and still inside every episode of the captured fault day. Do not change it without re-deriving it."
+  meter_freeze_s:
+    name: "Safety · Frozen-meter alarm after (s) — measured, do not change"
+    description: "MEASURED, NOT CHOSEN (SAFETY-18). How long the meter may keep answering with an UNCHANGED reading, while the command stands at the rail, before the add-on raises an alarm. Over 2399 s of this house at its settled operating point - 1194 polls, 735 of them repeating the previous reading - the longest run without a distinct reading is 15.4 s; 300 s is 19.5 times that and still inside the 900 s billing quarter. ALARM ONLY: it does not command 0 W and does not latch. ⚠️ Only the homewizard_local meter source can see this at all; on every other source the status page says NOT COVERED rather than armed. Do not change it without re-deriving it."
+  circulation_w:
+    name: "Safety · Circulating-power threshold (W) — measured, do not change"
+    description: "TWO OR MORE INVERTERS ONLY; with one inverter the quantity is identically zero. Two inverters pushing against each other net out to zero at the meter and are invisible to every other guard in this add-on. MEASURED ON 924 CLOSED-LOOP TEST RUNS in which nothing was faulty (SAFETY-31): the worst legitimate opposition collapses from 505 s at a 100 W threshold to 5 s at 400 W, and 400 W is the sharp knee this add-on will not let you go below - under it, ordinary operation holds the sensor over the threshold for minutes and nothing shorter than the billing quarter could tell that from a fault. 700 W is 1.75 times the knee, and the extra margin is there because the second inverter's ramp and lag are still copied from the first one rather than measured. Do not change it without re-deriving it."
+  circulation_hold_s:
+    name: "Safety · Circulating-power hold (s) — derived, do not change"
+    description: "TWO OR MORE INVERTERS ONLY. DERIVED (SAFETY-31): 75 s is fifteen control cycles - 15 times the worst legitimate episode the rig can produce, 2.5 times the firmware's own 30 s link veto, and twelve times inside the 900 s billing quarter. It is deliberately not a round 60 or 120, which would be a guess wearing a measurement's clothes. Do not change it without re-deriving it."
+  auto_start:
+    name: "Advanced · Start controlling automatically on boot"
+    description: "Off by default. Leave it off until the site has been commissioned: with it off, somebody has to press Start after every restart of the add-on, which is what you want while you are still checking signs and entities."
+  gain:
+    name: "Advanced · Loop gain"
+    description: "How much of the remaining error the loop corrects each cycle. MEASURED ON REAL HARDWARE and already at the limit - do not raise it. Lower is slower and safer."
+  slew_w:
+    name: "Advanced · Largest change per cycle (W)"
+    description: "How far the setpoint may move in one control cycle. ⚠️ 0 MEANS FOLLOW THE INVERTER RATING and is the recommended setting: the limit becomes about a ninth of the rating, so the loop takes the plant's own MEASURED settling time to cross its whole output range and the number cannot be left behind when the rating changes. DERIVED (SAFETY-39) from an ~18 s measured step response against a 2 s meter tick. A fixed number is accepted and is never silently reduced, but a number faster than the rating allows is refused at startup - at 1000 W against a 5000 W rating this loop drove the meter from 3.4 kW of export to 2.8 kW of import on 2026-09-05. Lower is always accepted."
+  deadband_w:
+    name: "Advanced · Deadband (W)"
+    description: "Errors smaller than this are ignored. ⚠️ The deadband is a one-way ratchet: any resting point inside it holds forever, and the meter's import register counts every positive watt with no export to cancel it - which is exactly why the resting point below is slightly negative."
+  target_grid_w:
+    name: "Advanced · Resting point at the meter (W)"
+    description: "What the meter should sit at when nothing is happening; negative means a slight export. -10 W is deliberate: resting at 0 W leaks about half the deadband in billed import all day - roughly 0.2 to 0.35 kWh at a 15 W deadband - and biasing the rest point below zero moves that leak into the export register, which is not billed. It costs about this many watts of given-away export, so keep it small."
+  step_w:
+    name: "Advanced · Setpoint quantisation (W)"
+    description: "The setpoint is rounded to a multiple of this before it is written, so the inverter is not handed a new number for every watt of noise."
+  saturation_w:
+    name: "Advanced · Saturation threshold (W)"
+    description: "The gap between what was commanded and what the inverter delivers that counts as 'this inverter is at a limit'. ⚠️ The per-inverter sign threshold under Safety is derived as exactly half of this, so moving this moves that measurement's argument with it."
+  saturation_cycles:
+    name: "Advanced · Saturated cycles before freezing (count)"
+    description: "How many consecutive saturated cycles before the loop stops winding up. ⚠️ Do not set this to 1: a single noisy cycle would then freeze the loop."
+  integrator_max_w:
+    name: "Advanced · Integrator bound (W, 0 means the same as the rating)"
+    description: "Caps how much stale error can be waiting to unwind when the sign flips. MEASURED on the closed-loop simulator with a 4000 W load dropped to zero: at a bound equal to the rating the command is 1000 W two cycles later, at 1.5 times the rating it is 1800 W. ⚠️ Do not raise it above the inverter rating - the output clamp already bounds what reaches the wire, so extra headroom buys nothing but wrong-direction watts after every saturation event. Lowering it below the rating is the useful direction, and the only reason this is a separate setting."
+  heartbeat_s:
+    name: "Advanced · Setpoint refresh interval (s)"
+    description: "How often the setpoint is rewritten even when it has not changed. It must stay well under the firmware's own watchdog, which vetoes a link that has been quiet for 30 s."
+  stale_input_s:
+    name: "Advanced · Command 0 W after inputs missing for (s)"
+    description: "How long the inputs may be missing before the add-on commands 0 W. With a P1 meter this clock starts only AFTER the meter staleness limit has already expired, so the two stack: the total is longer than this number on its own."
+  cycle_floor_s:
+    name: "Advanced · Longest gap between control cycles (s)"
+    description: "A deadline on the gap between cycles, reset by every cycle. On a healthy meter it never elapses and changes nothing. Raise it only if your meter is slower than about 10 s, and keep it under the meter staleness limit - past that there is no reading left to evaluate anyway."
+  log_level:
+    name: "Advanced · Log level"
+    description: "How much detail the add-on writes to its log. 'info' is the shipped setting; 'debug' and 'trace' are for diagnosing a problem and are noisy."

goodwe_controller/translations/nl.yaml

@@ -0,0 +1,255 @@
+# Home Assistant add-on-vertalingen - NEDERLANDS (UX-01)
+#
+# ⚠️ DIT IS GEEN WOORD-VOOR-WOORDVERTALING VAN en.yaml en hoort dat ook niet te
+# zijn. De eigenaar draait Home Assistant op Europe/Brussels; dit is de tekst
+# die een Vlaamse huiseigenaar leest, met de woorden die op zijn factuur en op
+# zijn digitale meter staan: afname en injectie, kwartierpiek en
+# capaciteitstarief, laadniveau, uitschakelgrens.
+#
+# ⚠️ DE TERUGVAL IS PER SLEUTEL. De frontend probeert eerst de taal van de
+# gebruiker, dan `en`, dan de kale sleutelnaam. Een sleutel die HIER ONTBREEKT
+# valt dus netjes terug op het Engels; een sleutel die hier STAAT maar fout is,
+# valt nergens op terug. Een half vertaalde sleutel weglaten is beter dan hem
+# verkeerd invullen.
+#
+# ⚠️ DE VOLGORDE WORDT HIER NIET BEPAALD. Het tabblad Configuratie rendert in de
+# volgorde van het `schema:`-blok van config.yaml; de volgorde hieronder is
+# alleen een spiegel daarvan, zodat beide bestanden gelijk lezen.
+#
+# ⚠️ AFGELEIDE CONSTANTEN VERMELDEN WAAR ZE VANDAAN KOMEN. Het tabblad toont een
+# getal dat uit 1890 gesloten-lustests komt en het omvormervermogen van de
+# eigenaar als hetzelfde soort veld. De beschrijving is de enige plek waar dat
+# verschil gezegd kan worden.
+configuration:
+  setpoint_entity:
+    name: "Hardware · Setpoint-entiteit van de omvormer"
+    description: "De ESPHome number-entiteit waar deze add-on het vermogen naartoe schrijft, meestal number.*_goodwe_setpoint_w. Dit is het enige wat de add-on aanstuurt. Laat leeg als u hieronder de lijst met omvormers invult: een installatie met een lijst mag niet óók één losse aansturing hebben, en de add-on start dan niet op."
+  soc_entity:
+    name: "Hardware · Entiteit met het laadniveau van de batterij (%)"
+    description: "De sensor die de laadtoestand van de batterij in procent doorgeeft. Gebruik de meting van de ESP32 zelf, geen waarde die elders berekend wordt. De onderhoudscyclus en alle ondergrenzen voor het laadniveau lezen deze sensor."
+  batt_entity:
+    name: "Hardware · Entiteit met het batterijvermogen (W)"
+    description: "De sensor die het batterijvermogen van deze omvormer doorgeeft, positief bij ontladen. Op deze installatie is dat holding register 0x0518, uitgelezen door de ESP32. Zowel de tekenbewaking als het alarm voor rondpompend vermogen beoordelen de omvormer aan de hand van deze meting."
+  batt_invert:
+    name: "Hardware · Teken van het batterijvermogen omkeren"
+    description: "Zet dit alleen aan als uw sensor ontladen als een negatief getal doorgeeft. De add-on gaat ervan uit dat positief ontladen betekent."
+  inverters:
+    name: "Hardware · Lijst met omvormers (leeg laten bij één omvormer)"
+    description: "Laat dit leeg tenzij er echt meer dan één omvormer staat. LEEG BETEKENT NIET 'nog niet ingesteld': het betekent dat de vier entiteiten hierboven, samen met het omvormervermogen en de uitschakelgrens van de batterij onder Grenzen, de ene omvormer beschrijven die u hebt. Dat is wat elke bestaande installatie leest, zonder dat iemand iets hoeft aan te passen. Vult u de lijst wel in, dan VERVANGT die de instellingen hierboven in plaats van ze aan te vullen, en wordt er niets overgenomen: elk item moet zijn eigen aansturing, zijn eigen vermogen en zijn eigen uitschakelgrens vermelden, zodat geen enkele omvormer ooit beoordeeld wordt op de cijfers van een andere. De losse setpoint-entiteit hierboven moet dan leeg blijven."
+    fields:
+      name:
+        name: "Naam"
+        description: "Een korte aanduiding voor deze omvormer, bijvoorbeeld inverter-a. Ze geeft deze omvormer een eigen naamruimte voor haar veiligheidsvergrendeling, hartslag en schrijfadministratie in het statusbestand van de add-on, dus twee omvormers mogen er niet één delen."
+      setpoint_entity:
+        name: "Setpoint-entiteit"
+        description: "De eigen ESPHome-entiteit number.*_goodwe_setpoint_w van deze omvormer. Twee items mogen niet dezelfde entiteit noemen - twee schrijvers op één aansturing wordt bij het opstarten geweigerd."
+      max_w:
+        name: "Vermogen van deze omvormer (W)"
+        description: "De bewaakte bovengrens van wat er naar DEZE omvormer geschreven mag worden; het plafond van de installatie is de som over de lijst. Verplicht bij elk item: een item zonder deze waarde zou een vermogen moeten lenen, en een omvormer beoordelen op de cijfers van een andere is precies de fout die deze lijst per omvormer moet wegnemen."
+      bms_soc_floor:
+        name: "Uitschakelniveau van de batterij (%)"
+        description: "Het percentage waarbij het batterijmanagementsysteem van DEZE batterij uitschakelt. Lees dit af van de batterij die er werkelijk staat (register 0x0560) voordat die batterij ooit aangestuurd wordt; neem geen waarde van een andere omvormer over. Bewust verplicht bij elk item: optioneel maken zou neerkomen op een standaardwaarde, en één standaardwaarde voor twee verschillende batterijen beschermt de kleinste batterij met het getal van de grootste."
+      soc_entity:
+        name: "Entiteit met het laadniveau (%) (optioneel)"
+        description: "Het laadniveau van deze batterij zelf. Laat leeg als deze omvormer dat niet doorgeeft - dat is wat het betekent, en er wordt nooit teruggevallen op de sensor van een andere omvormer."
+      batt_entity:
+        name: "Entiteit met het batterijvermogen (W) (optioneel)"
+        description: "Het batterijvermogen van deze omvormer zelf, positief bij ontladen. Laat leeg als deze omvormer dat niet doorgeeft; er wordt niets van een ander item overgenomen."
+      batt_invert:
+        name: "Teken van het batterijvermogen omkeren (optioneel)"
+        description: "Alleen voor dit item: zet dit aan als de sensor van deze omvormer ontladen als een negatief getal doorgeeft."
+  estop_fitted:
+    name: "Hardware · RS485-noodstop is geplaatst"
+    description: "Of de RS485-noodstop fysiek geïnstalleerd is. Dit stuurt alleen de waarschuwingsbalk op de statuspagina aan en verandert niets aan de regeling."
+  meter_source:
+    name: "Meter · Waar de meterstand vandaan komt"
+    description: "'off' houdt de losse Home Assistant-entiteit hieronder aan, waar een bestaande installatie op draait tot u iets anders kiest. ha_dsmr luistert mee met de DSMR-integratie; mqtt_p1 leest een MQTT-topic; ha_signed leest één entiteit met teken, wat een HomeWizard P1 publiceert; homewizard_local bevraagt de lokale API van de meter zelf en slaat Home Assistant helemaal over. ⚠️ Alleen homewizard_local kan 'de meter heeft niet geantwoord' onderscheiden van 'de waarde is niet veranderd', en is dus de enige bron waarop het alarm voor een vastgelopen meter iets betekent."
+  meter_entity:
+    name: "Meter · Entiteit met het netvermogen (W)"
+    description: "De sensor met het netto netvermogen, gebruikt wanneer de meterbron 'off' is. POSITIEF MOET AFNAME VAN HET NET BETEKENEN. Staat dit omgekeerd, dan stuurt de regeling de batterij de verkeerde kant op; gebruik daarvoor de tekenschakelaar hieronder en geen template-sensor."
+  meter_invert:
+    name: "Meter · Teken van het netvermogen omkeren"
+    description: "Zet dit aan als uw netsensor afname van het net als een negatief getal doorgeeft."
+  meter_phases:
+    name: "Meter · Aantal fasen (1 of 3)"
+    description: "Moet overeenkomen met uw aansluiting. Een telegram met een ander aantal fasen wordt bij binnenkomst geweigerd en gelogd, zodat een verkeerde waarde meteen zichtbaar wordt als 'geen telegrammen aanvaard' in plaats van als een stil verkeerd getal. Het bereik aanvaardt 2, maar dat is geen echte Belgische aansluiting."
+  p1_host:
+    name: "Meter · Adres van de HomeWizard P1"
+    description: "Alleen voor meterbron homewizard_local: het adres van de meter zelf op uw netwerk, als host of host:poort, bijvoorbeeld 192.168.2.250."
+  meter_poll_s:
+    name: "Meter · Seconden tussen twee uitlezingen"
+    description: "Alleen voor meterbron homewizard_local. 5 s is het tempo waarin de meter zelf ververst, dus lager instellen levert niets op. Deze waarde moet ruim onder de verouderingsgrens hieronder blijven - de meting is nooit verser dan dit interval - en de add-on start niet op als ze eraan gelijk is of erboven ligt."
+  meter_max_age_s:
+    name: "Meter · Een meting is verouderd na (s)"
+    description: "Daarna geldt de netwaarde als ontbrekend. Op zichzelf stuurt dit nog geen 0 W aan: de teller 'invoer ontbreekt' onder Geavanceerd begint pas te lopen nadat deze verstreken is, en de twee stapelen. 30 s is zes uitlezingen speling bij het standaard uitleesinterval."
+  meter_mqtt_topic:
+    name: "Meter · MQTT-topic"
+    description: "Alleen voor meterbron mqtt_p1: het topic waarop de P1-metingen gepubliceerd worden."
+  p1_import_entity:
+    name: "Meter · Entiteit van het afnameregister (W)"
+    description: "Het afnameregister ZONDER teken. Wijs dit niet aan een template-sensor mét teken toe: de add-on berekent het nettovermogen zelf als afname min injectie, zodat de tekenafspraak in geteste code zit en niet in ongecontroleerde YAML."
+  p1_export_entity:
+    name: "Meter · Entiteit van het injectieregister (W)"
+    description: "Het injectieregister ZONDER teken, de tegenhanger van het afnameregister hierboven. Zelfde regel: geen template-sensor mét teken."
+  p1_net_entity:
+    name: "Meter · Entiteit met het nettovermogen mét teken (W)"
+    description: "Alleen voor meterbron ha_signed. ÉÉN sensor mét teken: positief is afname van het net, negatief is injectie. Splits die niet in twee template-sensoren op - de add-on doet die splitsing zelf, juist zodat ze getest is."
+  p1_phase_import_entities:
+    name: "Meter · Afname-entiteiten per fase (L1, L2, L3)"
+    description: "Optioneel, in de volgorde L1..L3. Nodig voor de kwartierpiek van het capaciteitstarief op een driefasige aansluiting. Het aantal items moet gelijk zijn aan het aantal fasen hierboven."
+  p1_phase_export_entities:
+    name: "Meter · Injectie-entiteiten per fase (L1, L2, L3)"
+    description: "Optioneel, in de volgorde L1..L3, naast de afname-entiteiten per fase hierboven. Het aantal items moet gelijk zijn aan het aantal fasen."
+  p1_phase_net_entities:
+    name: "Meter · Netto-entiteiten per fase mét teken (L1, L2, L3)"
+    description: "Alleen voor meterbron ha_signed. Optioneel, in de volgorde L1..L3, elk met hetzelfde teken als de netto-entiteit hierboven. Zelfde rol als de afname- en injectie-entiteiten per fase: de kwartierpiek van het capaciteitstarief op een driefasige aansluiting. Het aantal items moet gelijk zijn aan het aantal fasen."
+  max_w:
+    name: "Grenzen · Vermogen van de omvormer (W)"
+    description: "DIT IS UW GETAL, geen afgeleide waarde: de harde bovengrens van wat er ooit gestuurd mag worden, in watt. Zet het op wat uw omvormer werkelijk aankan, begin laag en verhoog het pas na de indienstname. Het wordt helemaal niet gelezen zodra de lijst met omvormers is ingevuld - elk item draagt dan zijn eigen waarde en het plafond van de installatie is hun som. Verschillende veiligheidsdrempels moeten eronder blijven; de add-on start niet op als er één niet aan voldoet."
+  bms_soc_floor:
+    name: "Grenzen · Uitschakelniveau van de batterij (%)"
+    description: "GEMETEN, niet gekozen: het percentage waarbij het batterijmanagementsysteem van de batterij ZELF stopt met ontladen, wat u hier ook instelt. Register 0x0560 leest 10 op de referentie-GW5000S-BP. Lees deze waarde af van de batterij die er werkelijk staat in plaats van dit getal over te nemen. Ze staat hier zodat de add-on een ondergrens voor de piekbewaking op of onder deze waarde kan weigeren: zo'n ondergrens kan nooit werken, het BMS wint altijd eerst, en de statuspagina zou een reserve tonen die niet bestaat. Wordt niet gelezen zodra de lijst met omvormers is ingevuld - elk item vermeldt dan de uitschakelgrens van zijn eigen batterij."
+  peak_cap_w:
+    name: "Grenzen · Streefwaarde capaciteitstarief (W)"
+    description: "DIT IS UW GETAL: het gemiddelde kwartiervermogen waar de piekbewaking onder probeert te blijven. Neem het over uit uw netcontract - in België is dit de kwartierpiek waarop het capaciteitstarief van uw distributiefactuur berekend wordt."
+  peak_forecast_entity:
+    name: "Grenzen · Entiteit met de kwartierprognose (W)"
+    description: "Optioneel. Een prognose van het gemiddelde vermogen in het lopende factuurkwartier. Laat u dit leeg, dan is er helemaal geen piekbegrenzing."
+  peak_soc_floor:
+    name: "Grenzen · Piekbewaking ontlaadt niet onder (%)"
+    description: "AFGELEID, niet gekozen (SAFETY-24): de referentiebatterij heeft 13,8 kWh bruikbaar en de zwaarste doorgerekende afvlakdag vraagt 878 Wh, oftewel 6,4 %, dus 20 % ligt tien punten boven de uitschakelgrens van de batterij zelf en laat de bewaking nog ongeveer 1,6 van haar zwaarste waargenomen dagen speling. ⚠️ DIT BEGRENST ALLEEN DE PIEKBEWAKING. Het is geen reserve voor de hele batterij: gewoon eigenverbruik ontlaadt er dwars doorheen en gaat door tot aan de uitschakelgrens van de batterij, en dit getal verhogen verandert daar geen tiende procent aan. Het moet strikt boven de uitschakelgrens van de batterij blijven, anders start de add-on niet op. Verander het niet zonder de afleiding opnieuw te maken."
+  price_provider:
+    name: "Tarief · Bron van dynamische prijzen"
+    description: "Waar day-ahead- of realtimeprijzen vandaan komen. 'off' is de standaardinstelling en betekent dat deze installatie op het vaste tarief hieronder draait, zonder handel. ⚠️ Dit vandaag aanzetten haalt prijzen op, controleert en publiceert ze, en verandert geen enkele energiebeslissing - er is nog niets dat de prijsreeks gebruikt. Het mag niet gecombineerd worden met de twee oude Home Assistant-prijsentiteiten verderop: twee prijsbronnen op één installatie, waarvan er stilzwijgend één wint, wordt bij het opstarten geweigerd in plaats van schijnbaar actief gelaten."
+  price_markup_eur_kwh:
+    name: "Tarief · Marge van de leverancier (EUR/kWh)"
+    description: "De marge van uw energieleverancier. De add-on telt die ALLEEN op wanneer de gekozen prijsbron ze niet al bevat - bij engie_dynamic, totalenergies_dynamic, eneco_eddy en manual_csv wordt ze genegeerd, en dat wordt ook gelogd, zodat ze nooit dubbel wordt aangerekend."
+  price_taxes_eur_kwh:
+    name: "Tarief · Heffingen en btw (EUR/kWh)"
+    description: "Belastingen en heffingen per kWh, opgeteld volgens dezelfde regel als de marge: alleen wanneer de gekozen prijsbron ze nog niet bevat."
+  export_price_eur_kwh:
+    name: "Tarief · Injectievergoeding (EUR/kWh)"
+    description: "Wat u krijgt voor een kWh die u op het net zet, alles inbegrepen. Eén getal en geen reeks: geen enkele leverancier hier publiceert een dynamische injectiecurve. In België ligt dit vaak dicht bij nul, wat op zich al sterk pleit voor eigenverbruik in plaats van injectie. De waarde mag negatief zijn - op een zomerse middag betaalt u soms om te injecteren."
+  static_profile:
+    name: "Tarief · Vast of dag/nacht-tarief (één regel JSON)"
+    description: "Uw vaste of dag/nacht-contract, geschreven als één regel JSON. AANBEVOLEN ZELFS BIJ EEN DYNAMISCH CONTRACT: hierop valt de add-on terug wanneer de prijsfeed uitvalt, en staat dit leeg dan blijft de installatie bij een dode feed helemaal zonder tarief achter. De periodes moeten elk dagtype precies één keer bedekken, zonder gat en zonder overlap - een gat wordt bij het opstarten geweigerd in plaats van opgevuld, want een verzonnen prijs is er één waarop een strategie zou handelen. Een volledig vast tarief is één periode van 00:00 tot 24:00 op alle dagen. De prijzen zijn ALLES INBEGREPEN; de marge en heffingen hierboven worden er niet bij opgeteld. Let op: een venster van 22:00 tot 07:00 voor ma-vr dekt zaterdagochtend NIET, dus een regel voor het weekend is noodzakelijk en niet decoratief."
+  price_csv_path:
+    name: "Tarief · CSV-bestand met prijzen"
+    description: "Alleen voor prijsbron manual_csv: waar in /share de add-on uw eigen prijsbestand leest."
+  price_feed_url:
+    name: "Tarief · Afwijkende URL voor de prijsfeed"
+    description: "Laat leeg om de eigen feed van de gekozen bron te gebruiken. Alleen een host die die bron zelf opgeeft, wordt aanvaard, zodat dit niet zomaar ergens naar kan verwijzen."
+  price_horizon_h:
+    name: "Tarief · Hoe ver vooruit prijzen ophalen (uren)"
+    description: "Hoeveel uur aan prijzen er bij de bron opgevraagd wordt."
+  price_timeout_s:
+    name: "Tarief · Time-out voor een prijsaanvraag (s)"
+    description: "Hoe lang één aanvraag bij de prijsbron mag duren voordat ze wordt opgegeven."
+  price_now_entity:
+    name: "Tarief · Entiteit met de huidige prijs (oudere prijsweg)"
+    description: "De oudere manier om aan een prijs te komen, behouden omdat ze weghalen de onderhoudscyclus op een draaiende installatie zijn enige prijssignaal zou afnemen. De add-on leest deze entiteit en het gemiddelde hieronder en leidt er precies één ding uit af - of het nu goedkoper is dan gemiddeld - wat alleen gebruikt wordt om tijdens de onderhoudscyclus in een goedkoop venster te laden. Mag niet gecombineerd worden met een dynamische prijsbron."
+  price_avg_entity:
+    name: "Tarief · Entiteit met de gemiddelde prijs (oudere prijsweg)"
+    description: "Het gemiddelde waarmee de huidige prijs vergeleken wordt. Alleen zinvol samen met de entiteit hierboven en, net als die, niet te combineren met een dynamische prijsbron."
+  arbitrage_enabled:
+    name: "Tarief · Handelen op het prijsverschil"
+    description: "Laden in het goedkoopste gepubliceerde uur en ontladen in het duurste, maar alleen wanneer het verschil de kosten van de volledige cyclus dekt. STAAT UIT in de standaardinstelling, met opzet: dit is de eerste strategie in de add-on die bewust energie tegen de meter in verplaatst, dus ze wordt bewust aangezet of helemaal niet. Ze heeft zowel een prijsbron als een P1-meter nodig, en de add-on weigert combinaties die niet kunnen werken in plaats van ze schijnbaar actief te laten."
+  cycle_cost_threshold_eur:
+    name: "Tarief · Kostprijs van één volledige laad/ontlaadcyclus (EUR/kWh)"
+    description: "Wat één volledige cyclus per kWh kost: slijtage van de batterij plus omzettingsverliezen. Een prijsverschil dat hier onder ligt, kost geld en levensduur en wordt dus niet verhandeld. ⚠️ DIT GETAL IS NIET AFGELEID UIT EEN METING. 0,10 is een productbeslissing en staat nog open bij de eigenaar (OPT-08). Bij deze waarde handelt een installatie met een vast dag/nachttarief helemaal niet - het realistische Belgische dag/nachtverschil is ongeveer 0,08 EUR/kWh - en dat is bij dit getal het juiste antwoord, geen fout."
+  arbitrage_soc_floor:
+    name: "Tarief · Handel ontlaadt niet onder (%)"
+    description: "De reserve die de prijshandel niet mag aanspreken. Bewust een andere instelling dan de ondergrens van het onderhoud: een handelsstrategie op de cijfers van de maandelijkse balanceercyclus richten, zou twee ongerelateerde keuzes aan één getal koppelen."
+  arbitrage_soc_ceiling:
+    name: "Tarief · Handel laadt niet boven (%)"
+    description: "De ruimte die de prijshandel niet mag volmaken. De tegenhanger van de ondergrens hierboven, en om dezelfde reden losgehouden van het onderhoudsdoel."
+  maintenance_enabled:
+    name: "Onderhoud · Maandelijkse batterijcyclus uitvoeren"
+    description: "Een bewuste diepe ontlading, gevolgd door volledig opladen en een rustperiode op vol, zodat het batterijmanagementsysteem zijn schatting van het laadniveau kan herijken en de cellen kan balanceren. Staat standaard uit."
+  maintenance_interval_days:
+    name: "Onderhoud · Minimum aantal dagen tussen cycli"
+    description: "De kortste tijd tussen twee onderhoudscycli."
+  maintenance_start_hour:
+    name: "Onderhoud · Uur waarop een geplande cyclus start"
+    description: "Lokaal uur, 0 tot 23, waarop een cyclus die aan de beurt is begint."
+  maintenance_discharge_w:
+    name: "Onderhoud · Ontlaadvermogen (W)"
+    description: "Hoe snel de cyclus de batterij leegtrekt; het overschot gaat naar het net. Boven het vermogen van de omvormer wordt dit BEGRENSD tot dat vermogen en niet geweigerd - de cyclus loopt gewoon door, alleen trager, en de statuspagina meldt dat. Standaard 2000, afgestemd op het standaardvermogen; verhoog eerst het omvormervermogen en dan pas dit."
+  maintenance_charge_w:
+    name: "Onderhoud · Laadvermogen (W)"
+    description: "⚠️ MOET GELIJK AAN OF LAGER ZIJN dan het vermogen van de omvormer; anders start de add-on niet op. Erboven vraagt het laden in een goedkoop venster meer dan de bewaakte grens toelaat, lost de arbiter die tegenstrijdigheid op naar 0 W, en zou het onderhoud op een standaardinstallatie stilzwijgend nooit laden in een goedkoop venster. Daarnaast wordt dit nog eens begrensd door de ruimte die de piekbewaking overlaat."
+  maintenance_soc_floor:
+    name: "Onderhoud · Ontladen tot (%)"
+    description: "De diepte waar de maandelijkse herijking bewust naartoe gaat, één keer per maand, met opzet. ⚠️ DIT IS NIET DE ONDERGRENS VAN DE PIEKBEWAKING: die geeft aan hoe diep een besparende ontlading op geen enkele dag mag komen. De juiste waarden verschillen echt - 11 hier tegenover 20 daar - en daarom zijn het twee aparte instellingen die niet samengevoegd mogen worden."
+  maintenance_soc_target:
+    name: "Onderhoud · Opladen tot (%)"
+    description: "Het niveau waar de laadfase naartoe werkt voordat de rustperiode begint."
+  maintenance_hold_min:
+    name: "Onderhoud · Op vol houden gedurende (minuten)"
+    description: "Hoe lang er op het streefniveau gebleven wordt zodat het batterijmanagementsysteem het balanceren van de cellen kan afmaken."
+  sign_disagree_w:
+    name: "Veiligheid · Drempel tekenbewaking (W) — gemeten, niet wijzigen"
+    description: "GEMETEN, NIET GEKOZEN (SAFETY-02). Zowel het uitgestuurde setpoint als de netmeting moet boven deze waarde liggen voordat hun tegengestelde tekens überhaupt als onenigheid tellen. Op de vastgelegde gezonde dag (23-08-2026) komt het teken in 93,4 % van de beoordeelde metingen overeen; op de vastgelegde foutdag (20-08-2026) ligt dat tussen 0,0 en 10,5 %, met tegengestelde periodes tot 1752 s. Er is geen reden om hieraan te sleutelen zonder een nieuwe meetcampagne die dat onderbouwt. De waarde moet onder het omvormervermogen blijven, anders kan de bewaking nooit aanslaan, en de add-on weigert die instelling."
+  sign_disagree_s:
+    name: "Veiligheid · Wachttijd tekenbewaking (s) — gemeten, niet wijzigen"
+    description: "GEMETEN, NIET GEKOZEN (SAFETY-02). Hoe lang het setpoint en de meter onafgebroken tegengesteld moeten blijven voordat de add-on 0 W stuurt en vergrendelt tot iemand de regeling opnieuw start. 180 s ligt midden in een zeer brede gemeten marge: de langste terechte tegengestelde periode op de gezonde dag duurt 30 s, terwijl de foutdag bij 300 s nog altijd 13 keer aanslaat. Verander dit niet zonder nieuwe metingen."
+  unit_sign_disagree_w:
+    name: "Veiligheid · Tekendrempel per omvormer (W) — afgeleid, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS; bij één omvormer doet deze instelling niets. AFGELEID UIT 1890 GESLOTEN-LUSTESTS op de testopstelling met twee omvormers (SAFETY-30), waarbij niets defect was, over het volledige bereik dat deze add-on toelaat voor versterking en volgsnelheid. 250 W is precies de helft van de verzadigingsdrempel, zodat het kleinste verschil dat hier zichtbaar is, exact de afwijking is waarbij de regeling zelf al zegt dat de omvormer niet volgt. Verander dit niet zonder de afleiding opnieuw te maken. De waarde moet onder het omvormervermogen blijven, anders kan ze nooit aanslaan."
+  unit_sign_disagree_s:
+    name: "Veiligheid · Wachttijd per omvormer (s) — afgeleid, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS. AFGELEID UIT 1890 GESLOTEN-LUSTESTS (SAFETY-30): 85 s is 8,5 keer de langste terechte tegengestelde periode die die tests opleveren (10,0 s), 2,8 keer het eigen veto van 30 s in de firmware, en minder dan de helft van de 180 s die de installatiebrede controle neemt. Verander dit niet zonder de afleiding opnieuw te maken."
+  site_sign_disagree_w:
+    name: "Veiligheid · Tekendrempel voor de hele installatie (W) — gemeten, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS. Dezelfde 300 W als de drempel voor één omvormer, BEWUST OVERGENOMEN (SAFETY-30): de onderbouwing hangt niet af van het aantal omvormers - rond nul is het teken ruis, de dode zone is 15 W, en er is één meter, wat er ook achter hangt. Verander dit niet zonder metingen die dat onderbouwen."
+  site_sign_disagree_s:
+    name: "Veiligheid · Wachttijd voor de hele installatie (s) — afgeleid, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS. AFGELEID UIT 1890 GESLOTEN-LUSTESTS (SAFETY-30), en bewust NIET overgenomen van de 180 s voor één omvormer. In die tests duurt de langste terechte tegengestelde periode bij 300 W 110 s met één omvormer en 215 s met twee, omdat het commando de volledige installatiegrens moet doorlopen aan een volgsnelheid die niet die van de installatie is. 180 s overnemen zou dus een vals alarm hebben opgeleverd bij de laagste versterking en volgsnelheid en een gewone belastingomkering van 2,2 kW. 325 s is 1,51 keer die waarde, blijft binnen het factuurkwartier van 900 s en binnen elke episode van de vastgelegde foutdag. Verander dit niet zonder de afleiding opnieuw te maken."
+  meter_freeze_s:
+    name: "Veiligheid · Alarm vastgelopen meter na (s) — gemeten, niet wijzigen"
+    description: "GEMETEN, NIET GEKOZEN (SAFETY-18). Hoe lang de meter mag blijven antwoorden met een ONVERANDERDE waarde, terwijl het commando op de grens staat, voordat de add-on alarm slaat. Over 2399 s van deze woning op haar ingeregelde werkpunt - 1194 uitlezingen, waarvan 735 een herhaling van de vorige waarde - duurt de langste periode zonder een nieuwe waarde 15,4 s; 300 s is 19,5 keer zoveel en blijft binnen het factuurkwartier van 900 s. ALLEEN EEN ALARM: er wordt geen 0 W gestuurd en er wordt niets vergrendeld. ⚠️ Alleen de meterbron homewizard_local kan dit überhaupt zien; bij elke andere bron meldt de statuspagina NIET GEDEKT in plaats van actief. Verander dit niet zonder de afleiding opnieuw te maken."
+  circulation_w:
+    name: "Veiligheid · Drempel rondpompend vermogen (W) — gemeten, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS; bij één omvormer is deze grootheid altijd nul. Twee omvormers die tegen elkaar in duwen, heffen elkaar aan de meter op en zijn onzichtbaar voor elke andere bewaking in deze add-on. GEMETEN OVER 924 GESLOTEN-LUSTESTS waarbij niets defect was (SAFETY-31): de langste terechte tegenwerking valt terug van 505 s bij een drempel van 100 W naar 5 s bij 400 W, en 400 W is de scherpe knik waaronder deze add-on u niet laat gaan - daaronder houdt gewone werking de sensor minutenlang boven de drempel en kan niets korter dan het factuurkwartier dat van een storing onderscheiden. 700 W is 1,75 keer de knik; die extra marge is er omdat het aanloopgedrag van de tweede omvormer nog gekopieerd is van de eerste en niet gemeten. Verander dit niet zonder de afleiding opnieuw te maken."
+  circulation_hold_s:
+    name: "Veiligheid · Wachttijd rondpompend vermogen (s) — afgeleid, niet wijzigen"
+    description: "ALLEEN BIJ TWEE OF MEER OMVORMERS. AFGELEID (SAFETY-31): 75 s zijn vijftien regelcycli - 15 keer de langste terechte episode die de testopstelling kan produceren, 2,5 keer het eigen veto van 30 s in de firmware, en twaalf keer binnen het factuurkwartier van 900 s. Het is bewust geen ronde 60 of 120, want dat zou een gok zijn in het jasje van een meting. Verander dit niet zonder de afleiding opnieuw te maken."
+  auto_start:
+    name: "Geavanceerd · Automatisch beginnen te regelen bij opstarten"
+    description: "Staat standaard uit. Laat het uit tot de installatie in dienst is genomen: zolang het uit staat, moet iemand na elke herstart van de add-on op Start drukken, en dat is precies wat u wilt terwijl u tekens en entiteiten nog aan het nakijken bent."
+  gain:
+    name: "Geavanceerd · Versterking van de regellus"
+    description: "Welk deel van de resterende afwijking de regeling per cyclus wegregelt. GEMETEN OP ECHTE HARDWARE en al aan de bovengrens - niet verhogen. Lager is trager en veiliger."
+  slew_w:
+    name: "Geavanceerd · Grootste verandering per cyclus (W)"
+    description: "Hoeveel het setpoint in één regelcyclus mag verspringen. ⚠️ 0 BETEKENT VOLG HET OMVORMERVERMOGEN en is de aanbevolen instelling: de grens wordt ongeveer een negende van dat vermogen, zodat de regeling er de GEMETEN insteltijd van de installatie over doet om haar volledige bereik te doorlopen en het getal niet achterblijft wanneer het vermogen verandert. AFGELEID (SAFETY-39) uit een gemeten stapresponsie van ~18 s bij een meterinterval van 2 s. Een vast getal wordt aanvaard en wordt nooit stilzwijgend verlaagd, maar een getal sneller dan het vermogen toelaat wordt bij het starten geweigerd - bij 1000 W tegen 5000 W dreef deze regeling de meter op 2026-09-05 van 3,4 kW injectie naar 2,8 kW afname. Lager wordt altijd aanvaard."
+  deadband_w:
+    name: "Geavanceerd · Dode zone (W)"
+    description: "Afwijkingen kleiner dan deze waarde worden genegeerd. ⚠️ De dode zone werkt maar één kant op: elk rustpunt erbinnen blijft eeuwig staan, en het afnameregister van de meter telt elke positieve watt mee zonder injectie die dat compenseert - en precies daarom staat het rustpunt hieronder licht negatief."
+  target_grid_w:
+    name: "Geavanceerd · Rustpunt aan de meter (W)"
+    description: "Waar de meter moet staan wanneer er niets gebeurt; negatief betekent een lichte injectie. -10 W is bewust gekozen: rusten op 0 W lekt de hele dag door ongeveer de helft van de dode zone aan gefactureerde afname - grofweg 0,2 tot 0,35 kWh bij een dode zone van 15 W - en het rustpunt onder nul leggen verplaatst dat lek naar het injectieregister, dat niet gefactureerd wordt. Het kost ongeveer evenveel watt weggegeven injectie, dus houd het klein."
+  step_w:
+    name: "Geavanceerd · Afronding van het setpoint (W)"
+    description: "Het setpoint wordt op een veelvoud hiervan afgerond voordat het geschreven wordt, zodat de omvormer niet voor elke watt ruis een nieuw getal krijgt."
+  saturation_w:
+    name: "Geavanceerd · Verzadigingsdrempel (W)"
+    description: "Het verschil tussen wat gevraagd werd en wat de omvormer levert dat geldt als 'deze omvormer zit aan een grens'. ⚠️ De tekendrempel per omvormer onder Veiligheid is afgeleid als precies de helft hiervan, dus deze waarde verschuiven, verschuift ook de onderbouwing daarvan."
+  saturation_cycles:
+    name: "Geavanceerd · Verzadigde cycli voor bevriezen (aantal)"
+    description: "Hoeveel opeenvolgende verzadigde cycli er nodig zijn voordat de regeling stopt met verder oplopen. ⚠️ Zet dit niet op 1: één ruiscyclus zou de regeling dan al bevriezen."
+  integrator_max_w:
+    name: "Geavanceerd · Begrenzing van de integrator (W, 0 betekent gelijk aan het vermogen)"
+    description: "Begrenst hoeveel oude afwijking er kan klaarstaan om af te bouwen wanneer het teken omslaat. GEMETEN op de gesloten-lussimulator met een belasting van 4000 W die naar nul valt: bij een grens gelijk aan het omvormervermogen staat het commando twee cycli later op 1000 W, bij anderhalf keer dat vermogen op 1800 W. ⚠️ Zet dit niet hoger dan het omvormervermogen - de uitgangsbegrenzing bepaalt toch al wat er naar de omvormer gaat, dus extra ruimte levert alleen watts in de verkeerde richting op na elke verzadiging. Lager zetten dan het omvormervermogen is de nuttige richting, en de enige reden dat dit een aparte instelling is."
+  heartbeat_s:
+    name: "Geavanceerd · Verversingsinterval van het setpoint (s)"
+    description: "Hoe vaak het setpoint opnieuw geschreven wordt, ook als het niet veranderd is. Dit moet ruim onder de eigen bewaking van de firmware blijven, die een verbinding die 30 s stil is geweest, blokkeert."
+  stale_input_s:
+    name: "Geavanceerd · 0 W sturen nadat invoer ontbreekt gedurende (s)"
+    description: "Hoe lang de invoer mag ontbreken voordat de add-on 0 W stuurt. Bij een P1-meter begint deze teller pas te lopen NADAT de verouderingsgrens van de meter al verstreken is, dus de twee stapelen: het totaal is langer dan dit getal op zich."
+  cycle_floor_s:
+    name: "Geavanceerd · Langste tijd tussen twee regelcycli (s)"
+    description: "Een uiterste termijn voor de tijd tussen twee cycli, die door elke cyclus opnieuw begint. Bij een gezonde meter verstrijkt hij nooit en verandert hij niets. Verhoog hem alleen als uw meter trager is dan ongeveer 10 s, en houd hem onder de verouderingsgrens van de meter - daarna is er toch geen meting meer om te beoordelen."
+  log_level:
+    name: "Geavanceerd · Logniveau"
+    description: "Hoeveel detail de add-on naar zijn logboek schrijft. 'info' is de standaardinstelling; 'debug' en 'trace' dienen om een probleem te onderzoeken en leveren veel tekst op."