Square Model Context Protocol Server (Beta)

This project follows the Model Context Protocol standard, allowing AI assistants to interact with Square's connect API.

Most people should use the hosted server. Square runs a remote MCP server at https://mcp.squareup.com/mcp with OAuth sign-in; see the Square MCP documentation for setup with your AI assistant. This repository is the local, self-hosted server: a starting point if you want to run your own copy. Code changes go through the generator described under Contributing.

Quick Start

Get up and running with the local server using npx. This runs the server on your own machine with your own access token; for the hosted server, see the note above.

# Basic startup
npx square-mcp-server start

# With environment configuration
ACCESS_TOKEN=YOUR_SQUARE_ACCESS_TOKEN SANDBOX=true npx square-mcp-server start

# local runs
npx /path/to/project/square-mcp-server

Replace YOUR_SQUARE_ACCESS_TOKEN with your actual Square access token. You can obtain your access token by following the guide at Square Access Tokens. You can also set environment variables before running the command.

Remote MCP Server

Square offers a hosted remote MCP server at:

https://mcp.squareup.com/mcp

The remote server is recommended: it uses OAuth, so you sign in with your Square account instead of creating and managing access tokens. Setup guides for Claude, ChatGPT, Goose and other assistants are in the Square MCP documentation. The older https://mcp.squareup.com/sse endpoint is still served for existing SSE configurations.

Configuration Options

Integration with AI Assistants

Goose Integration

To configure the Square MCP Server with Goose:

Remote MCP

To install the Square remote MCP in Goose, click this URL on a computer where Goose is installed:

goose://extension?cmd=npx&arg=mcp-remote&arg=https%3A%2F%2Fmcp.squareup.com%2Fmcp&id=square_mcp_production_remote&name=Square%20MCP%20Remote&description=Square%20Production%20MCP%20Remote

Or copy and paste the URL into your browser's address bar.

The commands below configure the local server (npx square-mcp-server start), not the hosted one:

# Automatic installation
npx square-mcp-server install

# Get URL for manual installation
npx square-mcp-server get-goose-url

The install command automatically updates your Goose configuration.

Claude Desktop Integration

For Claude Desktop integration, see the Model Context Protocol Quickstart Guide. Add this configuration to your claude_desktop_config.json:

Remote MCP

{
  "mcpServers": {
    "mcp_square_api": {
      "command": "npx",
      "args": ["mcp-remote", "https://mcp.squareup.com/mcp"]
    }
  }
}

This approach allows you to authenticate directly with your Square account credentials without needing to manage access tokens.

Local MCP

{
  "mcpServers": {
    "mcp_square_api": {
      "command": "npx",
      "args": ["square-mcp-server", "start"],
      "env": {
        "ACCESS_TOKEN": "YOUR_SQUARE_ACCESS_TOKEN",
        "SANDBOX": "true"
      }
    }
  }
}

Tool Reference

The Square MCP Server provides a streamlined set of tools for interacting with Square APIs:

Service Catalog

Square MCP Server provides access to Square's complete API ecosystem. Check out the Square API Documentation for detailed information about each service:

Usage Pattern

For optimal interaction with the Square API through MCP:

1. Discover: Use get_service_info to explore available methods

   get_service_info(service: "catalog")
   

2. Understand: Use get_type_info to learn parameter requirements

   get_type_info(service: "catalog", method: "list")
   

3. Execute: Use make_api_request to perform the operation

   make_api_request(service: "catalog", method: "list", request: {})
   

Development and Debugging

Using MCP Inspector

The MCP Inspector provides a visual interface for testing:

# Build the project
npm run build

# Start the inspector with the Square MCP Server
npx @modelcontextprotocol/inspector node dist/index.js start

Development Workflow

1. Clone the repository
2. Install dependencies: npm install
3. Start development mode: npm run watch
4. Run the server: node dist/index.js start
5. Test your changes using the MCP Inspector

Contributing

This repository is auto-generated from Square's OpenAPI Specification. While contributions are welcome, please note that changes will need to be incorporated into the generator that produces this code. Please open an issue to discuss proposed changes before submitting a pull request.