add-waste-check

name	add-waste-check
description	Add a new waste line (a detector for a specific waste pattern, e.g. a retry loop or a needless model upgrade) to the aireceipts receipt. Use when the user asks to detect a new waste pattern, add a waste check, or flag a specific inefficiency.
trigger	/add-waste-check

/add-waste-check — one waste pattern, one pure function

1. Spec first

/write-spec with a kill criterion: does this pattern actually occur in real transcripts, at what frequency, and is it non-redundant with an existing waste check? If you can't point to a real occurrence, don't build it yet.

2. Shape

A waste check is a pure function — (session) => WasteLine[] — deterministic, no model calls, no network (I1). It lives in src/pricing/waste/<name>.ts and is added to the waste-check registry (find the existing one; don't create a second).

Every emitted WasteLine must be traceable to specific tool calls in the transcript (I3) — no aggregate "this session seemed wasteful" without pointing at the calls.

3. Near-zero false positives is the bar

This is a cost tool, not a judgement tool (I6) — one false "waste" flag erodes trust fast. Ship with:

• Positive fixtures: real transcripts where the pattern occurs, named and committed.
• Negative fixtures: real transcripts that look similar but must NOT fire — these are the actual discipline; write more of these than positives.
• An eval-corpus entry: add the expected result to the eval corpus so CI fails if precision drops below the bar the spec sets.

4. Gate

Unmasked verification block, plus the FP battery (positives fire, negatives silent). src/pricing/** changes must not regress the Stryker mutation score.

5. Land

/build-spec as usual. If in the /improve loop, the value gate (a corpus you didn't author as fixtures) applies in addition to the FP battery above.