Petstore.com is an online pet-supplies store built on Shopify that exposes a first-class agent commerce surface. Alongside the human storefront it implements the Universal Commerce Protocol (UCP) over the Model Context Protocol (MCP) at /api/ucp/mcp, publishes a /.well-known/ucp merchant profile and a /agents.md (mirrored as /llms.txt) describing… - View it on GitHub