Skip to main content

​
ACP — Agentic Commerce Protocol

“An open standard for programmatic commerce flows between buyers, AI agents, and businesses.”

​
What Is ACP

ACP (Agentic Commerce Protocol) is an open standard created by Stripe that defines the protocol for programmatic commerce interactions between buyers, AI agents, and merchants. OpenAI ChatGPT is the first implementer of ACP. ACP is not a single API. It consists of two independent systems:
SystemDirectionHosted ByPurpose
Product FeedMerchant to OpenAIOpenAI platformProduct data synchronization
Agentic CheckoutAI agent to MerchantMerchant-hostedCheckout, payment, orders
Protocol Status: Beta (partner approval required) Spec Version History:
  • 2025-09-29 (initial release)
  • 2025-12-12 (fulfillment capabilities)
  • 2026-01-16 (capability negotiation)
  • 2026-01-30 (extensions, discounts, payment processors) — current latest
Official Resources:

​
The Two Systems of ACP

​
System 1: Product Feed (Product Data Sync)

Merchants push product catalog data to the OpenAI platform. There are two methods:
MethodFormatUse Case
SFTP File UploadParquet (zstd) / jsonl.gz / csv.gz / tsv.gzDaily full catalog snapshots
REST APIJSONReal-time incremental updates during the day
Best Practice: Daily SFTP full sync + API real-time pushes for changes (prices, inventory, promotions).

​
System 2: Agentic Checkout (Transaction Processing)

Merchants implement 5 API endpoints on their own servers. AI agents call these endpoints to complete transactions when a user confirms a purchase: 
POST   /checkout_sessions            Create a checkout session
GET    /checkout_sessions/:id        Query session status
POST   /checkout_sessions/:id        Update session (shipping address, buyer info, etc.)
POST   /checkout_sessions/:id/complete  Complete payment
POST   /checkout_sessions/:id/cancel    Cancel session
Payment credentials are securely transmitted through the Delegate Payment API (hosted by Stripe) — merchants never touch raw card numbers.

​
ACP vs. UCP Comparison

DimensionACPUCP
Created ByStripeGoogle with Shopify and others
First ImplementerOpenAI ChatGPTMultiple platforms
ArchitectureMerchant pushes data + merchant builds endpointsMerchant builds API endpoints
PaymentDelegate Payment (vault token)Payment Token Exchange
Current StatusBeta (application required)Open
CoverageProduct discovery + checkout + paymentCheckout + identity + orders + payment
EcosystemChatGPT ecosystemCross-platform / cross-AI

​
Merchant Onboarding Flow

  1. Apply for partner status — Submit an application at chatgpt.com/merchants
  2. Get approved — Stripe/OpenAI reviews merchant qualifications
  3. Configure SFTP — Set up the file upload channel
  4. Prepare product data — Format your catalog per the Product object specification
  5. Implement Checkout endpoints — Deploy 5 API endpoints on your server
  6. Integrate Delegate Payment — Connect to Stripe’s payment delegation API
  7. Test and launch — Validate with a small batch, then go live at full scale

​
Chapter Directory (8 Chapters)

​
Part I: Core Concepts

  1. ACP Core Concepts — Protocol architecture, four-party model, data flow
  2. Product Data Format — Product/Variant objects, pricing (minor units), media, availability

​
Part II: Data Synchronization

  1. File Upload Integration — SFTP specifications, sharding strategy, Feed Header
  2. REST API Integration — Feeds/Products/Promotions endpoints, authentication, idempotency

​
Part III: Transaction Capabilities

  1. Promotions Management — Promotion objects, discount types, active periods

​
Part IV: Quality and Operations

  1. Data Quality Best Practices — ID stability, URL encoding, description formats, prohibited content
  2. Testing and Validation — Small-batch validation, data compliance checks
  3. Frequently Asked Questions — Common questions during onboarding
ACP is currently in Beta and requires partner approval. This book is based on ACP spec version 2026-01-30 and the OpenAI Commerce documentation. For the latest onboarding policies, visit agenticcommerce.dev.