An introduction

What is the Agentic Commerce Protocol?

The Agentic Commerce Protocol, or ACP, is an open standard developed by OpenAI and Stripe and released in 2025 that lets AI agents complete purchases directly from merchants. It carries product selection, payment credentials, and order confirmation between the agent and the merchant's systems, and it is the checkout rail powering Instant Checkout in ChatGPT, with launch partners including Etsy and Shopify's merchant base. In one sentence: ACP is how an AI agent becomes a customer your systems can transact with.

Why protocols decide the category

Every prior commerce channel standardized around rails: credit card networks, ecommerce platforms, app stores. Agentic commerce is standardizing now, along two complementary tracks that arrived within weeks of each other.

ACP, from OpenAI and Stripe, standardizes the merchant side. It allows an agent to execute checkout while the merchant remains the merchant of record, keeping the customer relationship, fulfillment, and returns with the brand. It was announced in September 2025 alongside ChatGPT's Instant Checkout.

AP2, the Agent Payments Protocol from Google, is the payments industry counterpart, launched with dozens of partners across card networks and processors. It focuses on authenticating that an agent is authorized to pay on a human's behalf: mandates, credentials, and liability. One protocol makes the transaction possible; the other makes it trustworthy.

For brands, the strategic fact is that these rails are being laid now, and presence on them is closer to binary than gradual. A merchant either exposes structured product, pricing, policy, and inventory data an agent can transact against, or it is invisible to the fastest growing checkout surface of the decade. Bain projects 15 to 25 percent of United States ecommerce could flow through agents by 2030. Gartner puts 20 percent of digital commerce transactions on AI platforms by the same year.

What agent-transactable means

Being transactable to an agent is a legibility standard, not an advertising one. It requires accurate structured product data, machine readable pricing, shipping and returns policies an agent can parse, real time inventory, and checkout integration on the emerging rails. There is no bid to place. The ranking factor is whether the machine can read you correctly.

Common questions

Is ACP only for ChatGPT?

ACP launched powering ChatGPT's Instant Checkout, but it is published as an open standard that any agent surface or merchant can adopt.

How is AP2 different from ACP?

Broadly, ACP standardizes the merchant and checkout side, while AP2 standardizes payment authorization: proving an agent has a valid mandate to spend. They are complementary layers, not direct substitutes.

Do luxury brands need this if they do not discount or mass distribute?

Transactability is optional. Legibility is not. A brand may choose not to enable agent checkout, but if agents cannot read its products and policies accurately, the brand is misrepresented in answers whether it participates or not.