agenticweb.wiki

Agentic Commerce Protocol ACP

Pay The Agentic Commerce Protocol (ACP) is an open, REST-based interaction model that lets a buyer's AI agent (a "platform" such as ChatGPT) complete a checkout with a merchant's existing commerce stack, while the merchant remains the system of record for orders, payments, tax, and compliance [1]. It solves the discovery-to-checkout hand-off for conversational and agentic shopping: a client negotiates capabilities, creates and updates a CheckoutSession, and completes or cancels it, with optional delegated-payment tokens (/agentic_commerce/delegate_payment) so an agent platform can pass a payment method to a merchant without becoming a payment processor [1].

Overview

It does not define blockchain settlement, on-chain escrow, or a payment rail of its own — payments continue to run over the merchant's existing PSP relationship, and ACP is scoped explicitly to checkout session lifecycle, feed ingestion, and payment-handler negotiation, not returns, tax computation, or fraud modeling [1]. It is also not a discovery protocol: there is no published well-known path for finding ACP support at an origin; capability negotiation is bilateral and appears to be arranged per integration (RFC: capability_negotiation), so it cannot be probed generically the way UCP's /.well-known/ucp can.

As of the current state (2026-09), the specification uses date-based versioning with a complete snapshot per release; the latest stable release is 2026-04-17, adding a push-model Feed API, multi-item checkout examples, and 3-D Secure authentication flows, with active development continuing in an unreleased/ branch [1]. Governance sits with a Technical Steering Committee of up to seven organization seats, appointed by Founding Maintainers OpenAI and Stripe, who retain veto power scoped narrowly to five stated principles (mission, neutrality, security, protocol integrity, and considered decision-making) [2]. Meta has since joined as a third lead maintainer alongside OpenAI and Stripe [3].

Reference implementations exist from both founding maintainers: OpenAI's ChatGPT commerce surface and Stripe's Agentic Commerce integration, both documented on their respective developer sites [4][5]. Because the only adoption figures available come from the maintaining organizations' own materials, adoption here is recorded as claimed rather than independently measured. What remains unresolved: how "beta" status maps to production risk for merchants going live today, and whether the TSC's veto mechanism has ever been invoked in a real dispute.

Discovery and probe

Bilateral capability negotiation (per RFC: capability_negotiation) between agent platform and merchant; no fixed well-known path published

POST {origin}/checkout_sessions
parse:     Response includes an API-Version response/negotiation and a CheckoutSession object per the 2026-04-17 OpenAPI schema
on absent: Absence proves nothing generalizable: ACP endpoints and auth are negotiated per integration and not advertised at a fixed public path, so a failed probe only shows this origin/path pair is not configured, not that ACP is unsupported.

Not probed live: unsafe-post. The probe is POST /checkout_sessions, which creates a checkout on the merchant; never run unauthenticated.

History

Instances

Every instance with its source is listed on the instances page.

See also

References

  1. ACP is an interaction model and open standard maintained by OpenAI and Stripe, currently in beta, using date-based versioning; the 2026-04-17 release added Cart, Feed, Orders, authentication and MCP support. — https://github.com/agentic-commerce-protocol/agentic-commerce-protocol (2026-04-17) VERIFIED
  2. Governance: a Technical Steering Committee of up to 7 org seats; OpenAI and Stripe are Founding Maintainers with veto power exercised only against violations of five named principles (mission, neutrality, security, protocol integrity, considered decision-making). — https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/blob/main/docs/governance.md VERIFIED
  3. Meta has joined OpenAI and Stripe as a lead maintainer of the project. — https://github.com/agentic-commerce-protocol/agentic-commerce-protocol/blob/main/MAINTAINERS.md VERIFIED
  4. OpenAI publishes ACP-based Commerce documentation for building checkout flows in ChatGPT. — https://developers.openai.com/commerce/ REPORTED
  5. Stripe publishes Agentic Commerce documentation implementing ACP for merchants. — https://docs.stripe.com/agentic-commerce REPORTED

JSON · Markdown