Agentic commerce glossary
Plain, sourced definitions of the terms used across this site. Deep-link any entry.
- Agentic commerce
- Online commerce in which AI agents discover, decide and complete purchases on a person's behalf, rather than the person clicking through a storefront themselves.
- Agentic checkout
- The step where an AI agent finalizes a purchase with a merchant, passing order and payment details over a protocol such as ACP, while the merchant remains merchant of record.
- ACP (Agentic Commerce Protocol)
- Open standard co-developed by OpenAI and Stripe (announced 29 Sep 2025, Apache 2.0) that powers Instant Checkout in ChatGPT.
- AP2 (Agent Payments Protocol)
- Open, payment-agnostic protocol announced by Google on 16 Sep 2025 to authorize and execute agent-led payments; an extension of A2A and MCP.
- MCP (Model Context Protocol)
- Open standard from Anthropic (25 Nov 2024, MIT, donated to the Linux Foundation in Dec 2025) that connects AI agents to tools and data. The context layer of the stack.
- x402
- Open payment standard from Coinbase (6 May 2025, Apache 2.0) that carries native stablecoin payments over HTTP using the 402 status code.
- A2A (Agent2Agent)
- Protocol for communication between AI agents; AP2 is designed as an extension of A2A.
- Instant Checkout
- The in-chat purchase experience in ChatGPT, powered by ACP and built with Stripe, that lets users buy from merchants without leaving the conversation.
- Shared Payment Token (SPT)
- A Stripe payment primitive that lets an application like ChatGPT initiate a payment scoped to a specific merchant and cart total without exposing the buyer's credentials.
- Facilitator (x402)
- A service that verifies and settles x402 payments on-chain so that sellers do not need to run their own blockchain infrastructure.
- Merchant of record
- The entity legally responsible for a sale (payment, tax, fulfillment, support). Under ACP the merchant stays merchant of record; the agent only relays information.