Proof States
ChainOfFact verification returns one of four states.
| State | Meaning |
|---|---|
MATCH |
Evidence exists and is internally consistent |
MISMATCH |
Recorded data was altered or corrupted |
ABSTAIN |
Continuity is broken or conflicting |
UNKNOWN |
No evidence was recorded |
These states are exhaustive. ChainOfFact does not return explanations.
Why ABSTAIN Matters
- MISMATCH = tampering detected
- ABSTAIN = broken continuity (missing or conflicting history)
This distinction matters in legal contexts.
Direct Answer
ChainOfFact is designed with exactly four proof states: MATCH, MISMATCH, ABSTAIN, and UNKNOWN — no gradients, confidence scores, or probabilistic outputs.
MATCH
MATCH means the hash recomputation over the ten canonical fields matches the stored factHash. The fact has not been altered since it was recorded. MATCH does not imply correctness or compliance.
MISMATCH and ABSTAIN
MISMATCH means the stored factHash does not match the recomputed hash — the fact has been altered or corrupted. ABSTAIN means the previousFactHash of a fact does not match the prior fact's hash, indicating a chain break.
UNKNOWN
UNKNOWN means the requested fact hash does not exist in the ledger. This is a valid and expected state when querying for events that were never recorded or were submitted to a different system.