A log you cannot edit
A normal log is just text — editable, overwritable, and hard to trust after an incident. An audit log with a hash chain is different: every entry links to the one before it.
The hash chain in plain terms
Each entry stores a SHA-256 hash of the previous entry. Change any record and every hash after it no longer matches. Verifying the chain proves nothing was altered.
What gets recorded
- The agent, the action, and the decision.
- The reason — allowlist, risk tier, budget, injection score.
- Tokens, latency, and cost.
- The run id for the full trace.
Who needs it
Anyone whose agent touches real systems or real money. When a customer asks "what happened?", the answer is a query with a provable chain behind it.
Export it
The history exports as JSONL, so your records are not locked in a vendor format and can be fed into compliance or fine-tuning.