UCP, MCP, ACP: A Manufacturer's Guide to Agentic Commerce Protocols

If you're a manufacturer trying to understand agentic commerce, you'll quickly encounter three acronyms: UCP, MCP, and ACP. These are the protocols that define how AI agents discover, evaluate, and transact with businesses. Think of them as the standards that make it possible for an AI procurement agent to find your products and place an order.

Here's what each one does and why it matters for your business.

Universal Commerce Protocol (UCP)

Developed by Google in partnership with Shopify, UCP covers the full commerce lifecycle: product discovery, comparison, checkout, and order tracking. It's designed to be universal: any AI agent that supports UCP can discover and transact with any seller registered on the protocol.

For manufacturers, UCP should be the first priority. It has the broadest reach, the most active development, and the strongest backing. Registering your products on UCP means they can appear in Google AI Mode shopping results, Gemini-powered procurement flows, and any third-party agent built on Google's commerce infrastructure.

The practical requirement: structured product data (titles, descriptions, GTINs, pricing, availability) published through a UCP-compatible feed or API endpoint.

Model Context Protocol (MCP)

Developed by Anthropic (the company behind Claude), MCP enables AI models to connect with external data sources and tools. While not exclusively a commerce protocol, MCP allows AI agents to query your product catalogue, check pricing, and interact with your systems in real time.

MCP matters because the Claude ecosystem is growing rapidly, and many enterprise AI deployments use Claude-based agents. If a buyer's procurement agent runs on Claude, MCP is how it accesses your data.

The practical requirement: an MCP-compatible endpoint that exposes your catalogue, pricing, and availability data.

Agent Commerce Protocol (ACP)

Developed by OpenAI in partnership with Stripe, ACP focuses specifically on secure agent-to-merchant transactions. It handles checkout, payment processing, and order confirmation for purchases initiated by AI agents.

ACP is narrower in scope than UCP but important for closing the transaction loop, particularly for agents built on OpenAI's models.

The practical requirement: ACP-compatible checkout flow integrated with Stripe for payment processing.

Which to start with

For most manufacturers, the sequence is: UCP first (broadest reach), then MCP (growing ecosystem), then ACP (transaction-specific). You don't need all three on day one. Start with UCP and expand.

The real prerequisite for all three is the same: structured, machine-readable product data. Without that foundation, no protocol registration is possible.