OpenAI has launched Instant Checkout, letting U.S. users buy products inside ChatGPT. The feature runs on the open-sourced Agentic Commerce Protocol, co-developed with Stripe, and compatible with MCP and standard APIs. OpenAI is starting with Etsy sellers and plans to add over a million Shopify merchants, including Glossier, Skims, Spanx, and Vuori. Users tap Buy and confirm shipping and payment in chat. Subscribers can use stored cards. OpenAI takes a small merchant fee from the transaction. The protocol uses encrypted tokens and could pave the way for agentic shopping. The move targets the monetization of 700 million weekly users and could challenge Google’s referral model.