Universal Commerce Protocol · Interoperability Standard

Connect Platforms, Businesses & Payment Capabilities with UCP

UCP (Universal Commerce Protocol) enables platforms and agents to complete discovery, negotiation, and transaction orchestration without binding to specific business implementations through standardized Profiles, Services, and Capabilities.

Get Started Core Concepts Specification

Discovery & Negotiation

Through Profile publication at /.well-known/ucp and platform-side Profile declarations, compute capability intersections and activate capability sets for each session.

Capabilities & Extensions

Capability as a functional unit, Extension enhances parent capability through extends. Schema uses allOf composition, supporting dynamic assembly per session.

Multi-Transport Bindings

UCP supports REST, MCP, A2A, and Embedded transport bindings; reuses the same capability and Schema semantics across different integration forms.

Security & Payment Boundaries

OAuth 2.0-based identity linking with minimal sensitive data exposure. Can combine with AP2 Mandates extensions for stronger cryptographic proof requirements.

Where to Start

Build an Overall View First

Start with the overview to understand the position of Profiles, capability negotiation, and Schema composition in a session.

Then Dive into Specifications & Capabilities

Start with the specification overview, then read by capability: Checkout / Identity Linking / Order.

Key Roles

Platform/Agent

Initiate discovery and checkout orchestration, declare Profile, and activate capability sets per session.

Business

Publish Business Profile, fulfill orders as Merchant of Record, and process payments.

Credential Provider

Manage sensitive data and issue tokens, reducing platform-side compliance scope.

Payment Service Provider

Host payment infrastructure, interfacing with business-side payment chains.