Agent-ready commerce via MCP

Install Crumb in ChatGPT, Claude, and Gemini

Plug one global MCP endpoint into your agent. Crumb handles catalog search, cart actions, and secure Square checkout links through deterministic tools.

Quick Install Generator
Endpoint URL
https://crumb.llc/mcp/claude

Install in 3 steps

1. Choose your agent

Pick ChatGPT, Claude, or Gemini in the install generator.

2. Paste endpoint in agent

Use the generated global endpoint for ChatGPT, Claude, or Gemini MCP setup.

3. Run a real shopping prompt

Ask for product discovery, cart creation, and checkout. Crumb returns a live Square payment link.

Claude setup

  1. 1In Claude Desktop/Code MCP settings, add a new HTTP server.
  2. 2Use the generated endpoint URL as the server URL.
  3. 3Run a checkout flow prompt to validate tool calls.
CLI command
claude mcp add crumb --url https://crumb.llc/mcp/claude

What agents can do after install

search_products
Agent can browse catalog and variants
create_cart
Agent starts a scoped cart for the active merchant
add_to_cart
Agent updates quantities and line items
create_checkout
Agent returns Square checkout link

Why Crumb improves agent commerce

Merchant isolation and auth guards prevent cross-merchant cart access.
Structured catalog + variant responses give agents higher answer accuracy.
Checkout is delegated to Square-hosted payment links.
Provider-specific MCP adapters support ChatGPT, Claude, and Gemini.