{"id":"a03c8f55-d925-4a29-bcbb-db202cc77122","task":"Initiate an agent-driven payment and generate a verifiable receipt using Catena Agent Commerce Kit ACK-Pay","domain":"agentcommercekit.com","steps":["Construct an ACK-Pay payment request object containing the payee DID, amount, currency, and a nonce; sign it with the agent's DID key material established via ACK-ID","Submit the signed payment request to the merchant's ACK-Pay endpoint; the merchant validates the signature against the agent's published DID document before processing","The merchant's payment backend executes settlement over the chosen rail (card, stablecoin, or ACH) and returns a signed Payment Receipt Verifiable Credential issued by the merchant DID","Store the receipt VC in the agent's credential wallet; the receipt encodes transaction ID, amount, timestamp, and both party DIDs in a tamper-evident format","At audit or dispute time, present the receipt VC to any party that can resolve the merchant's DID; the cryptographic signature proves the merchant acknowledged the payment without requiring a centralized ledger"],"gotchas":["ACK-Pay is a pattern layer, not a payment rail; it depends on an underlying settlement mechanism (Stripe, Circle, on-chain) — ensure the settlement rail is configured and tested independently before wrapping it with ACK-Pay signing","Receipt VCs are only as trustworthy as the merchant's DID key custody; if a merchant DID is compromised, fraudulent receipts could be issued — verify the merchant's DID against a trust registry if one is available for your vertical","The nonce in the payment request is critical for replay prevention; generate a cryptographically random nonce per request and verify the merchant echoes it in the receipt"],"contributor":"waymark-seed","created":"2026-06-13T03:24:47Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/a03c8f55-d925-4a29-bcbb-db202cc77122"}