MySQL MCP Server

An MCP server for interacting with MySQL databases.

This server supports executing read-only queries (query) and write queries that are ultimately rolled back (test_execute).

Setup

Environment Variables

Add the following environment variables to ~/.mcp/.env:

MYSQL_HOST=host.docker.internal  # Hostname to access host services from Docker container
MYSQL_PORT=3306
MYSQL_USER=root
MYSQL_PASSWORD=your_password

Note: host.docker.internal is a special DNS name for accessing host machine services from Docker containers. Use this setting when connecting to a MySQL server running on your host machine. If connecting to a different MySQL server, change to the appropriate hostname.

mcp.json Configuration

{
  "mcpServers": {
    "mysql": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "--add-host=host.docker.internal:host-gateway",
        "--env-file",
        "/Users/username/.mcp/.env",
        "my-mcp/mysql"
      ]
    }
  }
}

Usage

Starting the Server

docker run -i --rm --add-host=host.docker.internal:host-gateway --env-file ~/.mcp/.env my-mcp/mysql

Note: If you're using OrbStack, host.docker.internal is automatically supported, so the --add-host option can be omitted. While Docker Desktop also typically supports this automatically, adding the --add-host option is recommended for better reliability.

Available Commands

1. Execute Read-only Query

{
  "type": "query",
  "payload": {
    "sql": "SELECT * FROM your_table"
  }
}

Response:

{
  "success": true,
  "data": [
    {
      "id": 1,
      "name": "example"
    }
  ]
}

2. Test Query Execution

{
  "type": "test_execute",
  "payload": {
    "sql": "UPDATE your_table SET name = 'updated' WHERE id = 1"
  }
}

Response:

{
  "success": true,
  "data": "The UPDATE SQL query can be executed."
}

3. List Tables

{
  "type": "list_tables"
}

Response:

{
  "success": true,
  "data": ["table1", "table2", "table3"]
}

4. Describe Table

{
  "type": "describe_table",
  "payload": {
    "table": "your_table"
  }
}

Response:

{
  "success": true,
  "data": [
    {
      "Field": "id",
      "Type": "int(11)",
      "Null": "NO",
      "Key": "PRI",
      "Default": null,
      "Extra": ""
    },
    {
      "Field": "name",
      "Type": "varchar(255)",
      "Null": "YES",
      "Key": "",
      "Default": null,
      "Extra": ""
    }
  ]
}

Implementation Details

Implemented in TypeScript
Uses mysql2 package
Runs as a Docker container
Accepts JSON commands through standard input
Returns JSON responses through standard output
Uses host.docker.internal to connect to host MySQL (compatible with both OrbStack and Docker Desktop)

Security Considerations

Uses environment variables for sensitive information management
SQL injection prevention is the implementer's responsibility
Proper network configuration required for production use
Appropriate firewall settings needed when connecting to host machine services