Create a cryptographically signed, timestamped receipt proving that an agent performed an action. Call this immediately after any consequential action (approving an invoice, validating a supplier, sending a payment instruction, making a decision affecting a person) to build an audit trail that satisfies record-keeping obligations such as EU AI Act Articles 12 and 26. Pass the action details; if you include a payload it is SHA-256 hashed and immediately discarded — contents are never stored. Returns the signed receipt JSON, which verifies offline.

Check that an agent-receipts/v1 receipt is authentic: validates the Ed25519 signature, schema, and payload-hash format, and reports whether the receipt matches the copy stored in the vault. Use this before trusting a receipt presented by another agent or system.

Export all receipts in a date range as a signed audit bundle for a compliance officer or auditor. The bundle includes a tamper-evidence report: sequence gaps (deleted receipts) and hash-chain breaks are flagged. Timestamps are ISO 8601; omit both to export everything.

Return the service manifest: receipt schema version, signing key id, and the Ed25519 public key (base64 SPKI DER) to pin for offline verification.