Extends ADR-0022 with inspection/telemetry surfaces that turn the
forward-semantic-control claim from "mechanism exists" into "mechanism
is causally load-bearing, isolated, and replayable."
Changes (zero runtime semantics change beyond a pipeline bug fix):
- AdmissibilityTraceStep + GenerationResult.admissibility_trace —
per-transition record of region label, candidates before/after,
selected destination, and the typed AdmissibilityVerdict.
- ChatResponse + CognitiveTurnResult expose admissibility_trace,
admissibility_trace_hash, ratification_outcome,
region_was_unconstrained.
- hash_admissibility_trace + compute_trace_hash fold the new fields
only when they carry non-default values, so pre-ADR-0023 turn
hashes remain byte-preserved.
- Same-path ablation leg in evals/forward_semantic_control/runner.py:
generate(..., region=None) vs generate(..., region=R) on the same
runtime/vocab/field/persona/prompt — isolates the region as cause.
- Lane expansion: 8 dev cases across 4 relation axes (cause, means,
precedes, part_of) including 2 adversarial distractor cases.
- Lane metrics now report region_only_constrained_rate /
region_only_gap / ratified_rate / demoted_rate / passthrough_rate /
passthrough_on_scored.
- Bug fix surfaced by the new accounting: _ratify_intent looked up
runtime.vocab (always None) instead of runtime.session.vocab —
every production turn was silently PASSTHROUGH. Fixed; ratifier
now actually gates intent classification.
- tests/test_admissibility_trace.py: hash determinism +
pre-ADR-0023 byte-preservation tests.
Lane evidence (dev, 8 cases):
- constrained_pass_rate=0.80, causality_gap=0.80
- region_only_gap=1.00 (5/5 with region, 0/5 without — same path)
- ratified_rate=1.00, passthrough_on_scored=false
- overall_pass=true
Bench: 9.41s / 20 turns (~470ms/turn), well inside the +5% budget.
Full pytest: 922 passed, 1 pre-existing failure
(test_language_pack_cache, unrelated to ADR-0023).
c504796165