Agent Action Evidence Ledger

The problem

What did the agent claim it did, and was that history altered?

After an agent-driven change goes wrong, the reconstruction usually depends on chat logs and tool transcripts that nobody can prove were not edited — and they live in the same storage as the party under review.

What it does

Each recorded action — a proposal, an execution, a redaction or a later annotation — becomes an entry chained to the one before it. Any range can be exported as a self-contained document and verified from its own bytes, with no access to the original store. Redaction is a recorded event rather than a deletion, so removing a sensitive value neither breaks the chain nor erases the fact that something was removed.

How it works

Entries are canonicalized deterministically and hashed with SHA-256 via Web Crypto; verification is a pure function of the exported bytes, which is what makes third-party checking possible. Storage is a caller-provided sink, so the ledger lives wherever the operator already keeps evidence. A rejected durable append leaves the chain head unchanged and consumes no sequence number.

Tool surface

MCP over stdio. Compatible with Claude Code, Claude Desktop and Cursor, or usable directly as a TypeScript library. No API key, account or Tenable product is required.

• record_action

  Record one agent action — proposal, execution, redaction or annotation — as the next chained entry.

• export_ledger

  Export a self-contained, verifiable range of the ledger.

• verify_ledger

  Verify an exported document using only its own bytes; no live store is consulted.

• describe_policy

  Publish the redaction allowlist, hash algorithm, canonicalization and export versions, clock-skew bound and size limits.

What it deliberately does not do

• ·It never prevents, approves or executes an action — it observes and attests.
• ·A hash chain proves internal consistency; it does not prove when an entry was written without external anchoring, which is reported separately from chain validity.