OpenAI's Agentic Commerce Protocol: a technical look at how ChatGPT becomes a shopping agent

Last week, OpenAI launched a redesigned shopping experience in ChatGPT. 900 million weekly users can now browse products visually, compare options side-by-side, and get real-time pricing — all inside the conversation. The protocol powering it is called ACP (Agentic Commerce Protocol), an open standard co-developed by OpenAI and Stripe under Apache 2.0. And the technical implementation is worth a closer look. What ACP actually is ACP defines a common language for AI agents and merchants to coordinate transactions. Think of it as an API contract between ChatGPT (the buyer's agent) and a merchant's product catalog. Key architectural principle: OpenAI is not the merchant of record. Merchants retain full control over products, pricing, payments and fulfillment. ChatGPT is just the conversational intermediary. The protocol lives on GitHub with 1,300+ stars and 192 forks: github.com/agentic-commerce-protocol/agentic-commerce-protocol The pivot nobody expected OpenAI originally launched ACP in