Your agent log proves what happened.
Ours proves you didn't write it afterwards.

Drop in a Vetro ledger or an OpenTelemetry GenAI trace from the agent you already run — nothing to install. A log you hold proves nothing about when it existed: you own the file, so you could have written it this morning. This service checks it and countersigns its digest as an independent party, at a time you do not control.

Verify

Free

  • Hash-chain and ed25519 signature check
  • OTel GenAI traces accepted as-is
  • Event count, LLM and tool calls, cost
  • EU AI Act report preview
  • Nothing is stored

Check a ledger or an OTel trace

Bring the trace you already have

If your agent exports OpenTelemetry spans with the GenAI semantic conventions — OpenLLMetry, OpenInference, Langfuse, or your own instrumentation — export the OTLP/JSON payload and paste it here. It is converted into a hash-chained ledger, checked, and mapped onto the EU AI Act obligations exactly like a native ledger. An imported trace carries no signature of yours, which is precisely why the third-party countersignature is the only timestamped proof attached to it; the attestation says so explicitly in its source field.

What you are actually buying

The CLI is open source: you can already verify your own ledger, render the report and sign it with your own key. You cannot sign it as someone else. The countersignature is a statement by a party with no stake in your logs — that this exact digest, with this event count, verified clean at this timestamp — and that is the part an auditor, a customer or a court can weigh.

The attestation is a small JSON object: the statement, the signature, the public key. Verify any attestation, from anyone, for free:
curl -X POST /api/verify-attestation -H 'content-type: application/json' -d @attestation.json

Limits, stated plainly