HARD GATE — Define evals before implementation. Code graders = runnable verify: commands; model graders = explicit rubric with pass/fail criteria.

1. Name the capability under test (one sentence).

2. Write specs/EVALS-<feature>.md with:

   • Capability evals (does it do the job?)
   • Regression evals (did we break anything?)

3. Assign grader type per eval: code (shell verify) or model (rubric).

4. Assign strictness tier per eval (graduated promotion — e45s37):

   Tier	Meaning	Promotion rule
   EXPERIMENTAL	New eval, may flake	Not gating
   USUALLY_PASSES	Stable in dev; ≥2/3 recent runs pass	Blocks BUILD only when combined with ALWAYS_PASSES suite
   ALWAYS_PASSES	Zero tolerance; required for release	Any single failure blocks BUILD and merge

   Promote: EXPERIMENTAL → USUALLY_PASSES after 3 consecutive passes; USUALLY_PASSES → ALWAYS_PASSES after 5 consecutive passes with zero flakes documented in specs/state.yaml.

5. Run evals; log results table with pass@k (e.g. 3/3 runs) and tier per eval.

6. Block BUILD phase until all ALWAYS_PASSES evals pass at agreed k. USUALLY_PASSES failures warn; EXPERIMENTAL failures log only.

specs/verifications/eNNsYY-eval-report.md — see REFERENCE.md for template. Eval reports are stored alongside verification evidence in specs/verifications/, keyed by story ID for traceability.

→ verify: find specs/verifications -name "*-eval-report.md" | wc -l | awk '{if($1>0) print "OK: "$1" eval reports"; else print "MISSING"}'

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