The Universal Commerce Protocol (UCP) is Google's standard for making products discoverable and purchasable inside AI-powered experiences such as Google Search and the Gemini app.
It lets merchants expose their catalog to Google's AI surfaces; PayPal announced support for UCP in early 2026, becoming a checkout option within Google's AI shopping.
UCP is distinct from Google's Agent Payments Protocol (AP2), which governs how agents make payments on a user's behalf.