Overview
- Google says UCP will underpin native checkout in AI Mode within Search and the Gemini app for eligible U.S. retailers, starting with Google Pay and adding PayPal soon, with retailers remaining the seller of record.
- The specification was co-developed with Shopify, Etsy, Wayfair, Target and Walmart to reduce bespoke integrations across the commerce stack.
- UCP is designed to interoperate with Agent2Agent (A2A), Agent Payments Protocol (AP2) and the Model Context Protocol (MCP).
- Google signals plans to expand the capability globally in the coming months and to add features such as related product discovery, loyalty rewards and customizable shopping experiences.
- Developers outline early implementation patterns such as a /.well-known/ucp discovery manifest, modular capabilities for discovery, checkout and fulfillment, and note strict low-latency demands for agent requests.