What is Agentic Commerce Protocol (ACP)?

The Agentic Commerce Protocol (ACP) is an open specification that standardizes how an AI assistant and a merchant transact — the cart, the checkout session, and the delegated payment token — so any compliant merchant can accept an agent-placed order. It is the contract behind in-assistant 'instant checkout' experiences. ACP is one of several converging efforts in 2026: alongside it, Agent Payments Protocol (AP2), backed by card networks, focuses specifically on the authorization step (proving and cryptographically binding a human's mandate to the transaction), and the large commerce platforms expose their own native agent-checkout endpoints. The practical implication for most brands is that they do not implement ACP directly — they inherit agentic checkout through their platform integration, and direct ACP/AP2 implementation is reserved for merchants large enough to run their own checkout at scale.