Agent Ready CheckoutEdition . The pay layer for agents.

Guide

How an agent checkout actually flows, per protocol

In short

In every live flow the agent never becomes the seller: it discovers the product, builds a cart or session, obtains a scoped token or one-time card after the user approves, and hands it to the merchant, who charges through its own processor.

What the sources say

  • UCP: the business publishes a profile at /.well-known/ucp; the platform sends its own profile URI in the UCP-Agent header; capabilities are negotiated and a payment handler is chosen from the payment_handlers registry. ucp.dev, read 4 Nov 2026.
  • Google UCP checkout: the shopper pays with details saved in Google Wallet; Google passes standard card numbers (FPANs) and the merchant charges through its PSP. support.google.com, read 4 Nov 2026.
  • ACP: the merchant hosts checkout session endpoints the agent creates, updates and completes; the payment arrives as a delegated token such as a Stripe Shared Payment Token. github.com, read 4 Nov 2026.
  • A Stripe Shared Payment Token is a scoped grant to the seller with a currency, maximum amount and expiry. docs.stripe.com, read 4 Nov 2026.
  • Link Agent Wallet: the agent creates a spend request, the user approves, and Link returns a one-time-use payment credential. docs.stripe.com, read 4 Nov 2026.
  • x402 and MPP: the server answers HTTP 402 with payment requirements, the client pays and retries; MPP returns a Payment-Receipt header. mpp.dev, read 4 Nov 2026.
  • AP2: the agent collects a Checkout Mandate and a Payment Mandate as signed credentials before payment, for human-present or human-not-present purchases. ap2-protocol.org, read 4 Nov 2026.

Profiles named in this guide

Read next

Sources

  1. UCP specification overview, read 4 Nov 2026
  2. Merchant Center help: UCP-powered checkout, read 4 Nov 2026
  3. ACP repository README, read 4 Nov 2026
  4. docs.stripe.com/agentic-commerce/concepts/shared-payment-tokens.md, read 4 Nov 2026
  5. Stripe Link Agent Wallet docs, read 4 Nov 2026
  6. Machine Payments Protocol, read 4 Nov 2026
  7. AP2 protocol site, read 4 Nov 2026

Last reviewed