clay-borg/workplans/CB-WP-0019-the-am4-family.md

---
id: CB-WP-0019
kind: meta
title: "Budgets: what the meta budget is for, AM-4b's scope, and the self-quoting rule"
status: todo
state_hub_workstream_id: "ecf35aae-8549-4338-9e13-21dcf14c1130"
---

# Purpose

```
structural tier  M   (changes how the loop constrains its own operation:
                      a budget's scope and target, and a reporting rule)
chaos            d8 = 5  → no override
declared tier    M
```

Declaration 2 of chaos window 2, and **the first roll at d8**.

**Meta budget is 0%** over the trailing three, all product. ADR-0006 D2
exempts instrument repair anyway, and this is the repair four evidence
files have listed as owed.

## Two numbers that have been owed for five passes

Both were measured before this declaration, so the work is scoped against
facts rather than an intention to find them.

**AM-4b's scope**, owed since CB-EV-0012 §3:

| | crates | lines |
|---|---:|---:|
| AM-4b as instrumented (`games-ground`, `--edges normal`) | 29 | 317,021 |
| the whole workspace, dev edges included | 57 | 725,258 |
| **uncounted** | **28** | **408,237** |

**The dev-toolchain budget is blind to more source than its own target
of 350,000.** `criterion`, `clap`, `ciborium`, `quick-js` and now
`cb-game-runtime`'s dev graph are all invisible to it.

**AM-4b's proc-macro share**, owed since ADR-0008 D2: **109,585 lines,
15.1%** of the real graph.

That 15.1% is worth stating plainly, because it **vindicates a decision
made for the right reason**. ADR-0008 D2 refused to correct AM-4b using
AM-4a's measured 36.2%, saying *"correcting a second instrument on the
strength of the first one's ratio is the error this change exists to
fix."* The shares are 36.2% and 15.1%. Borrowing would have been wrong by
a factor of more than two.

## Task: give AM-4b a scope, and a target that matches it

```task
id: CB-WP-0019-T01
status: done
priority: high
state_hub_task_id: "b6b209c5-ecd7-4685-aa96-d0bc4d9c0df1"
```

Decide what AM-4b is **for**, then instrument that.

The two honest candidates, and the choice needs an argument rather than a
default:

- **Widen it** to the whole workspace with dev edges — everything a
  contributor's `cargo test` acquires. Then the target must move with the
  instrument, exactly as ADR-0008 D3 moved AM-4a's, and **the target moves
  to fit the measurement, not the measurement to fit the target.**
- **Narrow the claim** to what it actually measures and rename it, if
  "one package's non-dev graph" is the thing worth bounding.

Whichever wins, **do not repeat ADR-0008 D3's generosity by reflex.** That
decision gave back a small rounding-up because a target with 1.5% of room
fails on a patch release; a target set 130% above the current reading
would not be a budget at all.

**Controls:**
- the mutation must still go red — AM-4b's row is currently enforced and
  must stay so;
- a test that the configuration measures what its name says: if it claims
  dev edges, a dev-only dependency must move the number. `quick-js` is the
  case to use, because it is dev-only and it is what exposed this.

**Done 2026-08-03.** **Widened.** AM-4b now asks *what a contributor
acquires* — `--workspace --edges normal,dev` — and reads **57 crates /
725,258** where it read 29 / 317,021.

The two budgets had the **same scope** while claiming to bound different
things, which is the whole defect. They now differ by construction:
AM-4a is `-p games-ground --no-default-features`, AM-4b is the workspace
with dev edges. `GameKernel.md` §5c states which question each asks.

**Target 745,000**, ~2.7% of room — the same margin ADR-0008 D3 gave
AM-4a, applied to a number that grew because the instrument was repaired
rather than because anything was added. **The target moved to fit the
measurement.**

Controls: `quick-js` must be visible to AM-4b and invisible to AM-4a, both
asserted — it is the dev-only crate that exposed the blindness in
CB-WP-0014, when it landed and the number did not move.

**And the pass was caught by its own earlier work, twice.** Changing the
target invalidated AM-4b's mutation find-string; `mutation-check
--self-test` reported it **build-free**, which is the check CB-WP-0015
added after AM-4a's mutation rotted unnoticed for two passes. Second
catch, first that cost nothing. Then the DFD gate caught `facts.toml`
carrying the stale 317,021/350,000.

## Task: the proc-macro share, decided not just measured

```task
id: CB-WP-0019-T02
status: done
priority: high
state_hub_task_id: "6a90d069-d300-42ff-9bf6-e793f60bcf5a"
```

15.1% is measured. What is owed is the **decision**: does the dev budget
exclude proc-macro crates as the shipped one does?

The shipped case was easy — a proc-macro never reaches a shipped binary,
so counting it in "what a game ships" was simply wrong. **The dev case is
not the same question.** A proc-macro *is* acquired, *is* compiled, *is*
unaudited third-party source on a contributor's machine, and the
acquisition rule (ADR-0007 D3) counts what the build causes to be fetched.

So the arguments point opposite ways and the answer is not inherited.
Decide it, and say which of the two rules governs when they disagree.

**Whatever is decided, ADR-0008 D2's note that AM-4b's share is unmeasured
must stop being true in the source.**

**Done 2026-08-03. Counted, not excluded — the opposite of AM-4a, on
purpose.**

AM-4a excludes proc-macros because they run in the compiler and never
reach a shipped binary; counting them in *"what a game ships"* was simply
false. AM-4b **counts** them, because ADR-0007 D3's acquisition rule
counts what the build causes to be **fetched**, and a proc-macro is
fetched, compiled and unaudited on a contributor's machine like anything
else. *"It does not ship"* is no answer to *"we downloaded it"*.

**The rule for when they disagree: the question each budget asks decides.**
That is what ADR-0008 D2 left open.

Measured share: **109,585 lines, 15.1%**, against AM-4a's 36.2% — so
ADR-0008 D2's refusal to borrow the ratio was right by more than a factor
of two. The `unmeasured` note is gone from `dep-weight.py` and the spec.

## Task: write the self-quoting rule down

```task
id: CB-WP-0019-T03
status: todo
priority: high
state_hub_task_id: "b473ab42-8fd9-47b1-8fd4-b181c75440be"
```

Six passes, six under-reports, both halves of the defect diagnosed, and
the rule still lives only in evidence files:

| pass | reported mid-flight | settled | under by |
|---|---|---|---|
| CB-WP-0009 | $6.73 | $11.31 | 40% |
| CB-WP-0011 | $4.23 | $7.02 | 40% |
| CB-WP-0012 | $8.82 | $14.52 | 39% |
| CB-WP-0013 | $5.78 | $8.26 | 30% |
| CB-WP-0015 | $15.14 | $22.70 | 33% |
| CB-WP-0017 | $5.19 | $9.48 | 45% |

**Six for six, always low, never by less than 30%.** That is not noise;
it is a systematic bias with two identified causes (CB-EV-0013 §5,
CB-EV-0015 §6):

1. a pass's window runs to the **next** pass's first commit, so the
   previous pass is not final until the one after it starts;
2. **a figure read earlier in a session is an in-flight figure regardless
   of whose name is on it** — quoting from memory defeats the rule even
   when the boundary is right.

Put it in `specs/InnerLoop.md` as a rule with both halves, and make
`loop-lint` check what it can. A rule that lives only in prose has been
re-derived three times already.

**The honest question to answer while writing it:** is the right rule
"quote two passes back", or "re-run the instrument at quote time", or
both? T03 of CB-WP-0018 used the second and it worked. Say which is load
bearing.

## Task: say what the meta budget is *for*, and set it at 80/20

```task
id: CB-WP-0019-T05
status: done
priority: high
state_hub_task_id: "a17f949c-ac86-4e7e-8a8a-8159e2d4ad45"
```

The maintainer, 2026-08-03:

> *"we should establish a rule for what the budget is for. The main budget
> should be spent on the task at hand while some of the budget should be
> spent on control, review and improvement of the process we use to propell
> us forward. We can make that 80/20 to start with and allow for increasing
> or lowering the meta budget based on the phase or task at hand."*

META-25 has a threshold and **no stated purpose** — which is why it has
been argued about as a number three times. Write the purpose first; the
number follows from it.

### The window and the ratio have to be chosen together

The budget is measured over a **trailing 3-pass window**. One meta pass
among three, at the same cost as its neighbours, is already **33%**. So a
20% soft line over three passes does not mean *"one pass in five is
meta"* — it means *"one in five **and** at half the cost of a product
pass"*, which pushes meta work toward being rushed rather than rare.

| window | what a 20% line requires of a meta pass |
|---|---|
| trailing 3 | costs **half** a product pass |
| **trailing 5** | costs **the same** as a product pass |

**80/20 over a trailing 5-pass window is the literal reading of the
instruction:** one pass in five, at normal cost. Adopt that, and say in the
spec that the ratio and the window are a pair — changing one without the
other changes what the rule means.

### The phase dial, and why it must not be a dial

*"increasing or lowering based on the phase or task at hand"* is right —
stage 0 and a stabilisation phase should not carry the same ratio. But a
threshold anyone may move is not a threshold, and this project has a
standing rule that a limit is fixed structurally rather than raised
(four loadability breaches, `make status`'s 40 lines).

So the phase setting must be **declared, argued, and expiring**, in the
same shape `gates.toml` already uses: a value, a reason, a `review_by`
after which it reverts to 20 unless re-argued. Raising it silently to pass
a breach is the failure this shape exists to prevent.

**Controls:** `status.py`'s self-test must cover the new window and ratio,
and must fail if a phase override has no reason or no expiry.

**Done 2026-08-03.** InnerLoop **v1.7**.

**The purpose is written first, and the number follows from it:** *most
spend on the task at hand; some on control, review and improving the
process that carries the work forward.* `make status` now prints it above
the figure, because a threshold with no stated purpose is what let this
number be argued three times.

**Soft 20% over a trailing 5**, and the self-test enforces that they are a
**pair**: `META_SOFT_PCT == 100 / TRAILING_PASSES`. Moving the ratio to 25
without moving the window turns it red — *"25% over 5 passes; one meta
pass at parity reads 20%"*. That invariant is the rule's whole content;
without it the two numbers drift and "80/20" quietly means something else.

**The phase setting is declared, argued and expiring**, in `gates.toml`
beside the gate it governs. Verified live: with a setting present the line
moves to 35%, prints its reason, and announces *"reverts to 20% on that
date unless re-argued"*. A setting with **no reason** or **no expiry** is
refused by `--self-test`, not honoured — so the line cannot be raised
quietly to pass a breach.

**Measured effect of the change**, which is the point of adopting it
rather than asserting it: the last five passes read **7%** against the new
20% line. The old rule read 0% over three. Neither is a breach; the new
one is measuring a window in which a meta pass can actually appear.

`InnerLoop.md` crossed the 400-line loadability limit three times while
this was written, and was fixed structurally each time — the meta-budget
arithmetic, the cost-per-response basis, and the two review case studies
moved to `InnerLoopReference.md`. **The limit was not raised**, per the
standing precedent it exists to enforce.

## Task: evidence

```task
id: CB-WP-0019-T04
status: todo
priority: high
state_hub_task_id: "b499acb2-b728-4db9-9714-c235fb6c6363"
```

`evidence/CB-EV-0017-*.md`.

- **The AM-4 family, closed or not.** Four defects found across five
  passes, none by looking for them. State whether any remain and whether
  the family is now trustworthy — and if a fifth is plausible, say where.
- **What five passes of being "owed" cost.** These two numbers were
  carried as open items in four consecutive evidence files. Either the
  carrying was cheap and correct, or it was a way of not doing the work;
  say which, with the cost.
- **Quote CB-WP-0018's cost by re-running the instrument.** Under the rule
  T03 writes down.
- **The meta budget's new shape**, and what it would have said about the
  last five passes had it been in force. If 80/20 over trailing-5 would
  have failed passes that were plainly right to run, say so — that is the
  ratio being wrong, not the passes.
- **Chaos: declaration 2 of 12 in window 2, first roll at d8.**