Defines the `expert` ledger tier (sixth status above `audit-passed`)
and the composition gate that governs every future promotion.
The gate composes ALL TEN ADR-0114a obligations plus three contract-
level checks:
- audit_passed predicate must hold
- correct_rate >= 0.60 on public AND sealed holdout splits
- signed expert_claims entry whose digest reproduces byte-equal
Numeric thresholds (load-bearing choices documented with rationale):
- correct_rate floor: 0.60 ("advanced" — above weak open-source LLMs,
forces real architecture work, raisable later)
- depth-curve flatness ε: 0.05 (accuracy(N) ≥ accuracy(d1) · 0.95^(N-1))
- drift tolerance from promotion: ±0.02
Documents the post-ADR-0120 sequence in Open Candidate Directions:
Phase 1: ADR-0121 first worked math promotion (likely deferral)
Phase 2: parser-expansion arc to lift sealed-GSM8K correct_rate
Phase 3: math expert promotion succeeds
Phase 4: second domain = symbolic_logic (60-70% of math substrate cost;
ProofWriter / PrOntoQA benchmark; same machinery class)
Phase 5: third domain = high-stakes refusal-centric (medical or legal;
wedge-sharpener; needs two prior successes first)
Phase 7: open candidate — multi-reviewer threshold signing for expert
No code lands with this ADR. Implementation ships under ADR-0120a
to keep the contract change reviewable independently.
The first promotion attempt (ADR-0121) will likely defer on the
correct_rate gate — current measurement is 0/1319 on real GSM8K.
That deferral IS the contract working as designed; same load-
bearing pattern ADR-0107 → ADR-0110 demonstrated for audit-passed.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>