# Machine-verifiable evidence

ChainRay attaches Chain Proof metadata to service responses so an agent can distinguish observed chain state from analysis.

## Decision contract

- Preserve _proof.dataHash, _proof.analysisHash, chain, block number or slot, and proof timestamp.
- Use GET /verify-proof?hash=... to verify a recent ChainRay data hash.
- Treat missing or degraded evidence as a lower-confidence result and request a fresh observation when needed.
- Evidence identifies provenance; it does not turn a heuristic into a deterministic fact.