---
type: Article
name: "What is UCP?"
id: "https://selfe.ai/insights/glossary/what-is-ucp"
url: "https://selfe.ai/insights/glossary/what-is-ucp"
publisher: "did:web:selfe.ai"
description: "Universal Commerce Protocol, the checkout protocol that completes a purchase once an AI agent has already been connected, identified and authorised, handing a business back a confirmed order instead of an unverified promise."
datePublished: "2026-09-15T16:25:20.643Z"
author: The Selfe team
---

# What is UCP?

> Universal Commerce Protocol, the checkout protocol that completes a purchase once an AI agent has already been connected, identified and authorised, handing a business back a confirmed order instead of an unverified promise.

## In short

- UCP completes a purchase once connection, identity and authorisation are already handled.
- A business gets a confirmed order out of it, not a promise a customer still has to go finish elsewhere.

Good for: Closing a purchase once everything else is already handled. Not good for: Any of the steps before it, connection, identity and authorisation are separate protocols entirely.

Everything else in the chain, connection, identity, spending authorisation, gets a purchase ready. UCP closes it: the business gets a confirmed transaction it can settle, rather than sending a customer off to finish the job on a website after the fact. It's the last of the four jobs an agent-completed purchase has to do.

## Good for

Closing a purchase once everything else is already handled.

## Not good for

Any of the steps before it, connection, identity and authorisation are separate protocols entirely.

## Act on this

- [Check whether an agent can buy from you](https://selfe.ai/agentic-commerce/buyability-check) — the free readiness scan.
- [Discover venues](https://selfe.ai/api/registry/discover) — `POST`, semantic browse across the registry.
- [Match a bookable answer](https://selfe.ai/api/registry/match) — `POST` with dates and party size.
- [Verify Selfe's identity](https://selfe.ai/.well-known/did.json) — `did:web:selfe.ai`.
- [Agent card](https://selfe.ai/.well-known/agent-card.json) — how to connect over A2A or MCP.