C1 coherence floor: a deterministic verifier that runs on every
candidate surface produced by the truth path, before assignment to
ChatResponse.surface. Rejects illegal articulations and routes them
to a bounded disclosure string — admission control with a
deterministic fallback, not normalization.
Active rules (R1 deferred during ratification — see ADR):
R2_aux_neg_requires_verb — "<aux> not <wrong-POS>" rejected
R3_be_neg_requires_predicate — "<be> not <verb>" rejected
Fail-open on unknown POS, fail-closed on explicit wrong POS.
Cognition eval byte-identical (100/91.7/100/100).
Original bug class — "Light reveals truth, right?" → "Right does not
thought." — now routes to "I do not have a reviewed articulation for
that yet." with grounding_source=none, walk_surface preserving the
rejected candidate, and telemetry carrying R2_aux_neg_requires_verb.
Files:
generate/realizer_guard.py NEW — pure verifier
chat/runtime.py hook on stub + main paths
chat/telemetry.py serialize guard fields
core/physics/identity.py TurnEvent +2 fields
evals/realizer_guard/run_holdout.py NEW — 6-prompt cluster
tests/test_realizer_guard_*.py NEW — 46 tests (unit/seam/holdout)
docs/decisions/ADR-0075-*.md NEW — ratified
Invariants pinned:
invariant_realizer_no_illegal_articulation
invariant_realizer_guard_byte_identity_on_currently_passing_cases
Lanes (excluding 1 pre-existing TestDemoPreambles failure unrelated
to C1, already present at 4426f38):
smoke 67/67 cognition 120/120(+1s) teaching 17/17
packs 6/6 runtime 19/19 algebra 132/132 full 2792/2793
