UCP: Universal Commerce Protocol, SDKs and integration

What UCP enables

UCP gives merchants and shopping agents a common language for catalogs, carts, checkout and orders. A merchant publishes the functions it offers and how to reach them. The agent can discover those functions and use them to make a purchase.

Connections with other protocols

UCP describes integration through REST and MCP, among other options. An assistant can use a checkout through an API call or an MCP tool.
The AP2 mandate extension carries verifiable customer approvals alongside the purchase. Receiving systems can check which transaction the customer authorised.
ACP also supports purchases through agents using its own interfaces. UCP organises supported functions and extensions through published profiles.

Versions and licence

Published version: v2026-08-25 · 2026-08-25
Working draft: —
The current documentation and main branch may differ from the published release.
Licence / terms: Apache-2.0
Licence and terms ↗

Specification and documentation ↗View this version ↗Project repository ↗

An example flow

A merchant publishes capabilities such as catalog search and checkout in its UCP profile.
The shopping agent reads the profile and uses the functions and versions supported by both sides.
The customer selects an item. The agent creates the checkout and receives price, shipping and payment options from the merchant.
With the customer's approval, the agent completes the checkout. The merchant returns the order status.

SDKs and examples

These libraries and examples help you get started. Each entry lists the language, package and supported version.

From the protocol projectTypeScript · JavaScript

UCP JavaScript SDK

Includes: Zod schemas and generated types

Package / module: @ucp-js/sdk

Version & compatibility: 0.5.1 · SDK line 0.5.x for UCP 2026-08-25

Code and instructions ↗Package registry ↗

From the protocol projectPython

UCP Python SDK

Includes: Pydantic models

Package / module: ucp-sdk

Version & compatibility: 0.5.0 · Beta · SDK line 0.5.x for UCP 2026-08-25

Requires Python ≥3.10 according to the manifest.

Code and instructions ↗Package registry ↗

Agentic Commerce AlliancePHP

UCP PHP SDK · Core

Includes: Framework independent PHP core for merchant integration. Includes models, capability contracts, signatures and discovery.

Package / module: ucp-php-sdk/core

Version & compatibility: 0.0.7 · UCP 2026-08-25 · PHP ^8.1

composer require ucp-php-sdk/core:^0.0.7

Code and instructions ↗Package registry ↗Getting started and examples ↗

Agentic Commerce AlliancePHP

UCP PHP SDK · Symfony bundle

Includes: Symfony integration with HTTP routes, controllers, configuration and storage adapters. Uses the PHP core as a dependency.

Package / module: ucp-php-sdk/symfony-bundle

Version & compatibility: 0.0.7 · UCP 2026-08-25 · PHP ^8.1; Symfony bundle for Symfony 6.4 and 7.x

composer require ucp-php-sdk/symfony-bundle:^0.0.7