# UCP

> An open standard for interoperability between commerce entities so AI agents can discover products, fill carts, and complete purchases — orchestrating A2A, AP2 and MCP across the commerce journey.

_The Agent Protocol Atlas · /protocols/ucp · [JSON](/api/protocols/ucp) · [all The Agent Protocol Atlas](/protocols)_

- **name:** UCP
- **full_name:** Universal Commerce Protocol
- **layer:** payments
- **creator:** Universal-Commerce-Protocol project (open standard; ucp.dev)
- **status:** active (open standard)
- **year:** 2026
- **one_liner:** An open standard for interoperability between commerce entities so AI agents can discover products, fill carts, and complete purchases — orchestrating A2A, AP2 and MCP across the commerce journey.
- **spec_url:** https://ucp.dev
- **snippet:**

```
UCP: an open standard enabling interoperability between commerce entities for agent-driven shopping.
```
- **abbreviation:** UCP
- **also_known_as:** Universal Commerce Protocol
- **canonical_spec_url:** https://ucp.dev/specification/overview
- **entity_uri:** https://github.com/universal-commerce-protocol/ucp
- **taxonomy_layer:** payments
- **sub_layer:** commerce-interoperability
- **protocol_type:** settlement
- **central_problem:** Gives AI agents a single open standard to interoperate across commerce entities — discovering products, building carts, and completing purchases — instead of integrating each retailer/payment stack bespoke.
- **maintainer:** Universal-Commerce-Protocol project (ucp.dev / github.com/universal-commerce-protocol)
- **governance_body:** — (verify-against-primary-at-build)
- **license:** Apache-2.0
- **maturity_tag:** emerging
- **current_spec_version:** v2026-04-08
- **spec_date:** 2026-04-08
- **launch_date:** — (verify-against-primary-at-build)
- **last_verified:** 2026-06-15
- **transport:** Open commerce-interoperability standard (orchestrates A2A / AP2 / MCP across the commerce journey)
- **core_mechanism:** UCP is an open standard for interoperability between commerce entities (retailers, agents, payment providers) covering the journey from product discovery through cart-building, checkout, and post-purchase. Secondary analyses describe it as orchestrating existing protocols — A2A for agent communication, AP2 for payments, and MCP for tool/data access — into one commerce layer.
- **discovery_endpoint:** UCP commerce endpoints (per the ucp.dev specification; implementation-defined)
- **settlement_type:** card-rail / payment-agnostic (delegates settlement to AP2-class rails)
- **adoption_metric:** — (verify-against-primary-at-build)
- **notable_adopters:** {"value":"Universal-Commerce-Protocol project","source":"https://github.com/universal-commerce-protocol/ucp"}
- **relationships:** {"predicate":"built_on","target":"a2a","note":"Secondary analyses describe UCP as orchestrating A2A for the agent-communication layer of commerce."}, {"predicate":"built_on","target":"ap2","note":"UCP delegates the payment leg to AP2-class settlement."}, {"predicate":"competes_with","target":"acp-commerce","note":"UCP and ACP (Agentic Commerce Protocol) both address agent-driven commerce/checkout interoperability."}
- **ideal_use_case:** Giving retailers, agents, and payment providers one open interoperability standard for agent-driven shopping end to end.
- **when_to_use:** When you want a full commerce-journey interoperability layer (discovery → cart → checkout → post-purchase) rather than a single checkout or payment protocol.
- **when_not_to_use:** When an in-conversation checkout (ACP) or a single payment mandate framework (AP2) already covers your need.
- **code_example:** // UCP orchestrates commerce protocols (schematic):
// agent --A2A--> retailer.discover(query)
// agent --AP2--> pay(cartMandate)
// retailer --MCP--> inventory.lookup(sku)
- **source:** Open commerce-interoperability standard, Apache-2.0, release v2026-04-08: https://ucp.dev and https://github.com/universal-commerce-protocol/ucp . Secondary attribution (Google/Shopify/Walmart, NRF 2026) and AAIF hosting per research §2 + trade press — flagged for primary verification at build (possible distinct 'UCP' efforts).
- **agent_readiness_link:** agent-readiness/x402
- **layer_legacy:** payment