Developer Manual
Independent verifiers
Read authoritative state and classify bounded evidence.
The verifier is the host-owned read path to the system that owns the fact being claimed. It is independent from the provider that attempted the mutation.
Required evidence
A verifier implementation should bind its read to the operation/effect identity, tenant or account scope, expected candidate, stable reference, revision or freshness information, and finality policy. It returns only evidence supported by the authoritative read:
| Observation | Meaning | Result |
|---|---|---|
PRESENT | The authoritative system supports the intended effect | COMMITTED |
ABSENT_FINAL | The authoritative system establishes final absence under its policy | DISPROVED |
INDETERMINATE | The read is unavailable, stale, contradictory, incomplete, or cannot establish finality | UNKNOWN |
The verifier must reject wrong-tenant, stale, malformed, contradictory, and insufficiently final evidence according to the host’s authoritative policy. It must not return “probably present” as commitment.
Separation rule
The provider attempts the change. The verifier reads the resulting state. Core classifies the verifier observation; it does not call either system. This separation is the central protection against treating transport success as business truth.