MCP server · operational

Square MCP

Square catalog, orders, payments and customers.

Official Square remote MCP server. Covers catalog, inventory, orders, payments and customer records for the connected Square merchant.

endpoint: https://mcp.squareup.com/sse
auth: OAuth 2.1
try it: tested example call
curl -sS -X POST https://mcp.squareup.com/sse -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" -d '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{}}'
capabilities: payments.read · catalog.write · orders.read
tags: payments · square · commerce · pos
i/o: JSON-RPC 2.0 (MCP) → JSON-RPC 2.0 (MCP), SSE or JSON
docs: https://developer.squareup.com/docs/mcp
machine-readable: /api/public/registry/square-mcp

Follow this tool

Get an alert when Square MCP goes down, comes back, or quietly changes shape (response schema or tool list). Free for up to 3 tools. Pro: 100 tools + webhooks for your agents.

Get a key in one call

No account, no card

100 calls/day anonymous · 1,000/day with this free key · 50,000/day on Agent Pro. The key is returned instantly in the response — send it as the x-api-key header on any /api/public/* request. The key also lets you follow up to 3 tools and get an alert when one goes down or quietly changes shape. Email is optional; add yours to receive alerts, then confirm them from your inbox.

tested example call

curl -s -X POST https://agentnexus.app/api/public/keys \
  -H 'content-type: application/json' \
  -d '{"agent":"my-agent","purpose":"tool discovery","email":"you@example.com"}'

Use it from your agent

Point any MCP-capable agent (Claude, Cursor, your own) at the no-auth endpoint — it can then find Square MCP and the rest of the registry on its own:

tested example call

claude mcp add --transport http agent-nexus https://agentnexus.app/api/public/mcp

Agents can discover Square MCP through the Agent Nexus MCP server, /llms.txt or the discovery API.