GraphQL MCP server

The MCP-GraphQL server enables Large Language Models (LLMs) to dynamically interact with GraphQL APIs by providing schema introspection and query execution capabilities. This server bridges the gap between LLMs and GraphQL data sources, allowing models to discover and utilize GraphQL endpoints.

Installation

Quick Installation

You can install the MCP-GraphQL server using npm:

npx mcp-graphql

For Claude Desktop users, you can install it automatically via Smithery:

npx -y @smithery/cli install mcp-graphql --client claude

Manual Installation for Claude

To manually configure the server for Claude:

{
    "mcpServers": {
        "mcp-graphql": {
            "command": "npx",
            "args": ["mcp-graphql"],
            "env": {
                "ENDPOINT": "http://localhost:3000/graphql"
            }
        }
    }
}

Configuration

Environment Variables

The server is configured using environment variables:

Environment Variable	Description	Default
ENDPOINT	GraphQL endpoint URL	http://localhost:4000/graphql
HEADERS	JSON string containing headers for requests	{}
ALLOW_MUTATIONS	Enable mutation operations	false
NAME	Name of the MCP server	mcp-graphql
SCHEMA	Path to a local GraphQL schema file or URL	-

Usage Examples

Basic Usage

Connect to a local GraphQL server:

ENDPOINT=http://localhost:3000/graphql npx mcp-graphql

Using with Authentication

Include authorization headers:

ENDPOINT=https://api.example.com/graphql HEADERS='{"Authorization":"Bearer token123"}' npx mcp-graphql

Enabling Mutations

By default, mutations are disabled for security. To enable:

ENDPOINT=http://localhost:3000/graphql ALLOW_MUTATIONS=true npx mcp-graphql

Using a Local Schema File

Instead of introspection, use a local schema file:

ENDPOINT=http://localhost:3000/graphql SCHEMA=./schema.graphql npx mcp-graphql

Using a Remote Schema

Use a schema hosted at a URL:

ENDPOINT=http://localhost:3000/graphql SCHEMA=https://example.com/schema.graphql npx mcp-graphql

Available Tools

The server provides two primary tools:

introspect-schema

This tool retrieves the GraphQL schema, which should be used first if you don't have direct access to the schema. It works with either:

• A local schema file
• A schema file hosted at a URL
• An introspection query

query-graphql

Execute GraphQL queries against the endpoint. Remember that mutations are disabled by default unless explicitly enabled.

Security Considerations

Mutations are disabled by default to prevent unintended data modifications. Before enabling mutations in production environments, carefully consider the security implications and ensure proper access controls are in place.

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "mcp-graphql" '{"command":"npx","args":["mcp-graphql"],"env":{"ENDPOINT":"http://localhost:3000/graphql"}}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "mcp-graphql": {
            "command": "npx",
            "args": [
                "mcp-graphql"
            ],
            "env": {
                "ENDPOINT": "http://localhost:3000/graphql"
            }
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "mcp-graphql": {
            "command": "npx",
            "args": [
                "mcp-graphql"
            ],
            "env": {
                "ENDPOINT": "http://localhost:3000/graphql"
            }
        }
    }
}

3. Restart Claude Desktop for the changes to take effect