TransactionsUCP · AP2 · consent · mandates

Agent commerce and payments

Standards and controls for product discovery, checkout, payment authorization, and evidence of user intent in agent-mediated transactions.

Use it when

  • An agent discovers products or advances a checkout across merchant and platform boundaries.
  • Payment authorization needs portable evidence of user intent.
  • Merchants, payment providers, and agents need interoperable transaction state.

Choose another layer when

  • Prototype demos that imply purchasing without a real consent and authorization model.
  • Storing raw payment credentials in agent memory or prompts.

Production path

Build it in this order

  1. 01

    Separate shopping from authorization

    Model discovery, cart changes, checkout, user confirmation, payment, fulfillment, and dispute evidence as distinct states.

    Quality check: No product or price change can silently reuse an earlier approval.

  2. 02

    Bind intent to the transaction

    Capture who authorized what, within which limits, for how long, and through which credential or mandate.

    Quality check: A verifier can match the final charge to the user's approved terms.

  3. 03

    Design for failure and dispute

    Use idempotency, signed evidence, status reconciliation, cancellation, refunds, and auditable handoffs.

    Quality check: Retries, partial failures, or compromised agents cannot create ambiguous duplicate charges.

Artifacts you may see

  • UCP capabilities
  • AP2 mandates
  • checkout state
  • payment evidence

Evidence ledger

Primary documentation behind this guide

Provider-specific behavior is sourced to that provider. Open standards are sourced to their specifications and official maintainers.