Agentic Commerce Protocol

The ACP specification splits a purchase into a product feed, a checkout and a payment step. In the product feed, the merchant sends its catalog with prices, availability and promotions to the AI platform. In the agentic checkout, the agent calls endpoints of the merchant to create a checkout session, update it when the buyer changes the cart or the shipping option, and then complete or cancel it. The merchant calculates tax and shipping, and the agent shows the result to the buyer.

For the payment step, the agent sends the card of the buyer to the payment service provider of the merchant, which returns a token. The Delegated Payment Spec binds that token to a maximum amount, a currency, one merchant, one checkout session and an expiry time, and the current version supports one-time use only. For merchants on Stripe, the token is the Shared Payment Token, which a platform can revoke at any time and which carries fraud signals from Stripe Radar, such as the likelihood of a stolen card.

OpenAI launched Instant Checkout in ChatGPT on 29 September 2025 as the first use of ACP. ChatGPT users in the United States on the Free, Plus and Pro plans could buy single items from US sellers on Etsy, and OpenAI announced Shopify merchants such as Glossier and SKIMS as the next step. The buyer tapped Buy and confirmed the order, shipping and payment in the chat, while Stripe powered the payment flow at launch. Merchants paid OpenAI a fee on completed purchases, and the service was free for buyers.

On 24 March 2026, OpenAI wrote that the first version of Instant Checkout did not offer the flexibility it wanted, so merchants may now use their own checkout while ChatGPT concentrates on product discovery. OpenAI extended ACP to product discovery and named Target, Sephora, Nordstrom, Best Buy, The Home Depot and Wayfair among the retailers that send their catalogs through the protocol. A merchant that wants a native purchase inside ChatGPT builds a ChatGPT app, as Walmart did with account linking, its loyalty program and Walmart payments.

OpenAI and Stripe are the founding maintainers of ACP and steer it through a technical steering committee with up to seven seats, one per organization. Meta joined that committee in April 2026 and now appears next to OpenAI and Stripe in the list of lead maintainers. OpenAI and Stripe intend to hand the protocol to a neutral foundation as it matures.

Merchants and payment providers that do not work with Stripe can implement the protocol with their own tokens. PayPal said in October 2025 that it would adopt ACP, process payments for merchants in Instant Checkout and bring the catalogs of its merchants into ChatGPT through one ACP server. A draft extension lets the agent run 3-D Secure 2 authentication with a provider the merchant names, which is relevant for card payments in Europe because strong customer authentication applies to them.

ACP and the Agent Payments Protocol (AP2) of Google start at different points of a purchase. ACP specifies the exchange between an agent and a merchant, from the product feed through the checkout session to the token for the payment provider of the merchant. AP2 specifies proof of consent, with signed mandates that record what the buyer asked for and approved, so that the merchant, the payment processor and the card network can check the authority of the agent.

The two protocols also record the approval of the buyer in different ways. In ACP the buyer confirms each order in the interface of the agent, and the limits of the token on merchant, amount and time carry that approval to the payment provider. In AP2 the approval is a signed digital credential that can also cover a later purchase without the buyer present, within limits set in advance. Card networks add a further layer, such as the Trusted Agent Protocol of Visa, with which a merchant recognizes the agent itself.

The Agentic Commerce Protocol is an open standard from OpenAI and Stripe for purchases that an AI agent completes on behalf of a buyer. It defines the product feed, the checkout session and the payment token, while the business stays the merchant of record. ACP is one of several protocols in agentic commerce, where AI agents find, choose and pay for goods on behalf of people.

Since March 2026, OpenAI lets merchants send buyers to their own checkout and concentrates ChatGPT on product discovery. ChatGPT still uses ACP for product feeds and promotions, and native purchases inside ChatGPT run through merchant apps such as the Walmart app.

The specification is public on GitHub under the Apache 2.0 license, with OpenAPI files for checkout and delegated payment and JSON schemas for the data. ACP uses dated versions, starting with the first release of 29 September 2025, and the latest stable version is dated 17 April 2026. The status of the protocol is still beta, and contributors sign a contributor license agreement.

A merchant can offer its ACP endpoints over a plain REST interface or over the Model Context Protocol, which connects AI agents to outside tools and data. The release of 17 April 2026 added MCP support to the specification, together with cart, feed, orders and authentication.