API · SDK · runtime · authentication lifecycle intelligence

Last updated · 9 September 2026

SchemaTrace

Breaking changes, enforcement dates and migration requirements.

ST-2026-110 · Removals & lifecycle enforcement

Shopify deprecates Storefront MCP cart tools in favour of UCP Cart MCP

Shopify deprecated the Storefront MCP server's get_cart and update_cart tools on 24 June 2026 and directs cart integrations to the UCP-conforming Cart MCP endpoint, with maintenance of the deprecated tools stated only through 31 August 2026.

ShopifyStorefront MCPCart MCPUCPget_cartupdate_cartcreate_cartcancel_cartdeprecation

Previous state

Storefront MCP cart integrations called get_cart and update_cart at https://{shop}.myshopify.com/api/mcp, and update behavior was tied to those earlier tool schemas.

Current state

The Storefront MCP get_cart and update_cart tools are deprecated. Shopify's UCP-conforming Cart MCP at https://{shop-domain}/api/ucp/mcp provides create_cart, get_cart, update_cart and cancel_cart, and update_cart replaces the cart's complete state.

Who needs to care

Apps and agents calling Storefront MCP get_cart or update_cart at /api/mcp, particularly implementations that patch individual cart fields or do not send the metadata required by Cart MCP.

What to do

Move cart calls to /api/ucp/mcp; include meta.ucp-agent.profile on every request; send a UUID meta["idempotency-key"] for cancel_cart; send the complete line_items array on each update_cart call; and validate against the updated request and response schemas.

What the source does not prove

Shopify says the deprecated tools would be maintained until 31 August 2026, but the notice does not state that the old endpoint was removed or disabled after that date. The replacement claim is limited to the four named Cart MCP tools and their documented request semantics.

Lifecycle history

Dated event sequence

  1. Deprecation announced

    Shopify deprecated Storefront MCP get_cart and update_cart and directed documentation and migrations to the UCP-conforming Cart MCP endpoint.

  2. Stated maintenance-through boundary

    Shopify said the deprecated Storefront MCP cart tools would be maintained until this date without announcing a removal date.

Evidence ledger

First-party sources

  1. 01
    Shopify — Storefront MCP cart tools are being deprecated in favour of UCP Cart MCP

    Official Shopify developer changelog · 2026-06-24

    Open official source ↗