SKILL.md
Factory Acceptance Test Skill
A FAT is the last moment a defect is the factory's problem instead of yours. This skill writes the plan (or the report) with the parts that actually get argued over at the line: which spec clause each test covers, how many units get pulled and at what AQL, what exactly fails a lot, and who signs — so acceptance is a decision with a name on it, not a vibe at the end of a factory visit.
What This Skill Produces
- A test coverage matrix mapping every test to the spec requirement it verifies
- A sampling plan (ANSI/ASQ Z1.4) with lot size, inspection level, and AQL per defect class
- Unambiguous pass/fail criteria and lot accept/reject rules
- Golden-sample handling procedure
- A deviation log format and a sign-off block with authority levels
Required Inputs
Ask for these if not provided; if the spec is thin, draft the matrix from the product description and mark rows [spec clause to confirm]:
- Product and spec — the requirements document or at minimum a feature/claims list
- Lot size — units in the lot(s) under acceptance
- Product risk profile — safety-relevant? battery? affects AQL choice
- Prior quality history — first article vs mature product (allows tightened/reduced inspection)
- Who signs — customer QE, factory QA, third-party inspector?
Sampling & Classification Framework
Defect classes and default AQLs (ANSI/ASQ Z1.4, General Inspection Level II, normal inspection — the consumer-electronics defaults; adjust with reason):
| Class | Definition | Default AQL |
|---|---|---|
| Critical | Safety hazard, regulatory violation, data loss | 0 — any occurrence rejects the lot |
| Major | Product fails to function, or defect the user will certainly notice and return | 1.0 (tighten to 0.65 for premium/first lots) |
| Minor | Cosmetic or workmanship issue within limit samples' tolerance but noted |