Adds a typed legality check that catches a narrow class of incoherent
finite-predicate surfaces before they ship. Scope is deliberately
narrow:
- generate/articulation_legality.py:
- SlotKind enum {VERB, NON_VERB, UNKNOWN}
- ArticulationLegality enum {LEGAL, ILLEGAL_NON_VERB_FINITE_PREDICATE}
- classify_predicate_slot_kind() — token allowlists for known verbs
and known non-verb nouns
- validate_finite_predicate_legality() — fails on negated +
NON_VERB; fail-open on UNKNOWN to preserve canary behavior
- generate/templates.py:
- _inflect_predicate: copular-aware negation
("is X" -> "is not X" instead of the default "does not be X")
- render_step: invokes the legality validator; returns
"I cannot realize that proposition coherently yet." when an
illegal shape is detected
The check is upstream of register / anchor-lens transforms (presentation
+ substantive axes both downstream of the realizer); no interaction
with R6 / ADR-0073 layering.
Tests pin:
- NON_VERB + negated -> ILLEGAL_NON_VERB_FINITE_PREDICATE
- UNKNOWN + negated -> LEGAL (fail-open preserved)
- render_step returns the disclosure string when illegal detected
- render_step still produces the fall-through surface on UNKNOWN
Validation:
- Cognition eval byte-identical (100/100/91.7/100)
- 370 realizer / lens / register / pack / lane tests pass
- anchor-lens-tour + register-tour both green
