[FEATURE] Tool for stamping agent outputs to a transparency log

Feature Area

Integration with external tools

Is your feature request related to a an existing bug? Please link it here.

NA

Describe the solution you'd like

A tool that takes text an agent produced and records a hash of it in a public append-only log, returning a Merkle root and a verify URL anyone can check without an account.

The use case is an agent whose output is later disputed — a decision, an approval, a generated document — where you need to show what the output was at the time it was produced, rather than re-asking the model. Verification is a plain GET, so it works for someone who was never party to the run.

Describe alternatives you've considered

Writing outputs to application logs, which the operator can edit; commercial notary APIs, which require an account to verify; hashing locally, which proves nothing about when.

Additional context

#6388 implements this as MarkovianStampTool and is written and tested (5 passing tests, ruff clean). It was closed by the first-time-contributor bot for having no linked issue. I'll reopen it against this issue with a corrected README — the current one conflates the per-item timestamp with the protocol's chain-level Bitcoin anchor, which are separate guarantees. The tool states plainly that it proves data existed, not that it is correct.

Willingness to Contribute

Yes, I'd be happy to submit a pull request

Start with the implementation and tests referenced in issue #6388, then review its corrected README. Check how the tool records output hashes, returns the Merkle root and verify URL, and distinguishes per-item timestamps from the chain-level Bitcoin anchor. Done means the documented guarantees are accurate and the existing five tests remain passing with ruff clean.