Integrate the Agentic Commerce ProtocolPrivate preview

Agentic Commerce Protocol (ACP) is an open-source specification for enabling commerce between compatible applications, such as ChatGPT, and sellers. You can implement it as a RESTful interface or MCP server.

You can use the Agentic Commerce Protocol to make your checkout accessible to applications for initiating and completing checkouts. Applications can securely share payment credentials, including Stripe’s SharedPaymentToken, for processing in your existing payment stack.

For example, in a typical checkout flow, the user interface, data model, and payment processing are entirely the responsibility of the seller. The seller presents a checkout page, stores data about the cart and order, collects payment credentials, and processes the payment.

In contrast, during an agentic checkout process, the AI agent is responsible for presenting the checkout interface and collecting payment credentials, while the seller is responsible for their existing data model and payment processing.

To learn more, see the ACP website.

Lifecycle

This section outlines the steps involved in the checkout process from the buyer’s initial intent to order through to payment confirmation by the seller.

1. The buyer expresses intent to order, and the agent initiates checkout with the seller with a CreateCheckoutRequest.
2. The seller processes the request, generating a cart, and any other artifact as usual, responding with the current checkout state.
3. The agent renders UI (a checkout interface, text, and so on) to relay the current state (for example, total) and options (for example, shipping) to the buyer.
4. After the buyer makes selections, the agent and seller communicate with each other using UpdateCheckoutRequest.
5. After the buyer expresses intent to pay, the agent provisions a SharedPaymentToken, set to the amount and the seller, and shares with the seller with a CompleteCheckoutRequest.
6. The seller creates a PaymentIntent and sends confirmation to the agent.

Endpoints

The seller makes their checkout available for agents to interact with by building out a RESTful HTTP interface to specification with the four following endpoints. Every endpoint response includes the current state of the checkout, acting as source of truth for the agent.

To manage the checkout process:

1. Create a Checkout object: Provide a unique SKU to generate the cart and checkout data in your backend. Your response includes details about supported payment methods, fulfillment options, and more.
2. Update a Checkout object: Update modifications such as line item quantities, fulfillment methods, and buyer details as the buyer navigates the checkout process.
3. Complete a Checkout object: Pass the SharedPaymentToken in a request. Process your payment during this request and respond with order details.
4. Cancel a Checkout object: Notify the agent of cancellation when the buyer exits or dismisses the checkout so you can release inventory and update the checkout status to canceled.

Events

After checkout completes, notify the agent about order creation and updates. For example, update the agent after an order has shipped. This enables the agent to communicate status changes, request actions, or share other information with the buyer.

Security

To maintain transaction integrity and protect sensitive information within the agentic commerce framework, follow these guidelines:

• All requests require HTTPS and include Authorization: Bearer {token}.
• Sign all webhook events and include an HMAC signature sent as a request header.
• The agentic application provides authorization and signing keys during onboarding.