Is Storefront MCP the same as UCP?

No. They are different. ARC counts cart results under UCP. The counting rule is on the methodology page.

Does ARC have its own MCP?

Yes, a free public MCP at /api/ask with no login.

What is Shopify Storefront MCP?

Storefront MCP is an endpoint on Shopify stores that lets AI agents search the catalog and work with carts using the Model Context Protocol (MCP). ARC checks whether a store's MCP server answers. ARC counts cart results under UCP. That split is on the methodology page.

What it is

Storefront MCP is Shopify's per-store server, usually at /api/mcp. An agent can list tools and call them. ARC counts a cart result on the UCP row, not as MCP transacts. That counting rule is on the methodology page.

MCP in one paragraph

The Model Context Protocol is a general way for an agent to list and call tools. It started at Anthropic and is now an open project. Storefront MCP is one shopping use of it, not the whole protocol.

What ARC checks

ARC sends tools/list to /api/mcp. If the server answers with at least one named tool, ARC counts the store as declared, valid and usable. On Shopify today that tool is often the policy and FAQ tool. A cart tool still listed there would be counted under MCP transacts. While no checked store lists one, transacts stays Not measured, and the cart results sit on the UCP row.

Relationship to UCP

They are not the same protocol. ARC counts cart results under UCP so MCP transacts is not read as "MCP failed". The counting rule is on the methodology page.

Live numbers

ARC open dataset snapshot 2026-10-12

Declared: 1,586 of 3,497 (45.4%)Measured/api/mcp answered a tools/list request with tools

Valid: 1,586 of 3,497 (45.4%)Measuredtools/list parsed with at least one named tool

Usable: 1,586 of 3,497 (45.4%)MeasuredA tool or catalog answered on /api/mcp (on Shopify today, the policy and FAQ tool; or a catalog tool returned the tested product)

Transacts: Not measuredNot measuredOf stores whose /api/mcp lists a cart tool, the cart tool returned a checkout link (stopped before payment). Not measured while no checked store lists one there.

Frequently asked questions

What is Shopify Storefront MCP?: Storefront MCP is an endpoint on Shopify stores that lets AI agents search the catalog and work with carts using the Model Context Protocol (MCP). ARC checks whether a store's MCP server answers. ARC counts cart results under UCP. That split is on the methodology page.
Is Storefront MCP the same as UCP?: No. They are different. ARC counts cart results under UCP. The counting rule is on the methodology page.
Does ARC have its own MCP?: Yes, a free public MCP at /api/ask with no login.

On ARC

Cite this: ARC, arcreport.ai, accessed 2026-10-13, CC-BY-4.0. Protocol figures: ARC open dataset snapshot 2026-10-12 (12 October 2026). Index browser figures: ARC open dataset snapshot 2026-10-12. Platform figures: ARC saved checks, accessed 2026-10-13.

Every figure is labelled Measured, Inferred or Not measured. Not measured is not zero. A missing result is not a mark against a store. ARC stops before payment.