TTP EXTENSION · MODEL CURRENTNESS

Model valid then ≠ model valid now.

Consequential artifacts should bind the causal-model identity that authorized their computation, and adoption should compare that identity with current model authority before trusting dependency values.

Canonical rule

COMPUTE UNDER M_then
↓
BIND model version + digest
+ dependency manifest
+ dependency values
+ artifact digest
↓
MODEL AUTHORITY MAY CHANGE
↓
RESOLVE M_now
↓
COMPARE M_then ↔ M_now
  ├─ same → compare current dependency values
  └─ different / unknown
       ↓
     compatibility proof?
       ├─ yes → revalidate under M_now
       └─ no  → HOLD / RECOMPUTE
↓
CURRENT OWNER ADOPTS
↓
FENCED COMMIT
↓
PROVE MODEL HISTORY → CURRENTNESS → EFFECT

I67–I70

• I67 — Model valid then ≠ model valid now.
• I68 — Artifact must bind the causal-model identity that authorized its computation.
• I69 — Adoption must compare artifact model identity with current model authority before value fingerprint.
• I70 — Model drift or unknown compatibility requires hold, revalidation, recomputation, or explicit compatibility proof before consequence.

Minimal decision

IF artifact.model_digest == current_model.digest
AND artifact.dependency_fingerprint == current_fingerprint(current_model)
AND current_execution_authority_is_valid
THEN eligible for adoption
ELSE hold / revalidate / recompute / prove compatibility

Exact model identity is a conservative default, not a universal compatibility algorithm. A newer model may preserve the validity of an older result, but that compatibility must itself become evidence.

Self-consistency under a superseded model is not current applicability.