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Hash Chain
Tamper-evident by construction.
Your audit trail isn't a log you have to trust — it's a cryptographic chain where any edit to the past breaks everything after it.
Each captured record stores a SHA-256 chain hash built from its commitments, selected operational metadata, and the hash of the record before it. The records link into a single chain; public anchoring is optional.
That design makes the trail tamper-evident. Changing a stored commitment or protected record field makes its recomputed hash differ; changing or deleting history also breaks the expected sequence or predecessor link. The verifier reports the affected sequence rather than silently accepting the change.
What that gives you
- Append-only in practice: the only way to keep the chain valid is to never rewrite history.
- Model provenance baked in: each hash folds in which model produced the call, so you can't quietly swap what answered.
- Independently re-computable: anyone with the chain can recompute it and confirm it's intact — no access to us needed.
- Outage-safe: the chain is append-only, so a backend outage never corrupts what's already recorded.
Prove your chain is intact.
See the chain build in real time and re-verify it live in a walkthrough.
See verification →
Foxy Audit