mssql-mcp-server

MSSQL MCP Server

A Model Context Protocol (MCP) server for connecting to Microsoft SQL Server databases. This server provides tools for executing SQL queries and managing database connections.

Version Notice: This project has been upgraded to use Model Context Protocol SDK 1.9.0. See for details.

Installation

Installing via Smithery

To install MSSQL MCP Server for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @c0h1b4/mssql-mcp-server --client claude

Manual Installation

npm install mssql-mcp-server

Usage

Add the server to your MCP settings configuration file:

{
  "mcpServers": {
    "mssql": {
      "command": "mssql-mcp-server",
      "env": {
        "MSSQL_CONNECTION_STRING": "Server=localhost;Database=master;User Id=sa;Password=yourpassword;",
        // Or individual connection parameters:
        "MSSQL_HOST": "localhost",
        "MSSQL_PORT": "1433",
        "MSSQL_DATABASE": "master",
        "MSSQL_USER": "sa",
        "MSSQL_PASSWORD": "yourpassword",
        "MSSQL_ENCRYPT": "false",
        "MSSQL_TRUST_SERVER_CERTIFICATE": "true"
      }
    }
  }
}

Tools

query

Execute a SQL query on a MSSQL database.

Parameters

• connectionString (string, optional): Full connection string (alternative to individual parameters)
• host (string, optional): Database server hostname
• port (number, optional): Database server port (default: 1433)
• database (string, optional): Database name (default: master)
• username (string, optional): Database username
• password (string, optional): Database password
• query (string, required): SQL query to execute
• encrypt (boolean, optional): Enable encryption (default: false)
• trustServerCertificate (boolean, optional): Trust server certificate (default: true)

Either connectionString OR (host + username + password) must be provided.

Example

const result = await use_mcp_tool({
  server_name: 'mssql',
  tool_name: 'query',
  arguments: {
    host: 'localhost',
    username: 'sa',
    password: 'yourpassword',
    query: 'SELECT * FROM Users',
  },
});

Running the Server

Local Development

# Install dependencies
npm install

# Run in development mode
npm run dev

# Build
npm run build

# Run the built server
npm start

Using Docker

# Build and start services (SQL Server + MCP server)
docker-compose up

# Or just build the Docker image
docker build -t mssql-mcp-server .

Testing

# Run tests
npm test

# Run tests with coverage
npm run test:coverage

Security

The server includes safeguards against dangerous SQL operations:

• Blocks potentially harmful commands like DROP, TRUNCATE, ALTER, CREATE, EXEC, etc.
• Validates all input parameters and database names
• Sets reasonable limits on query length and timeout
• Uses connection pooling for better performance and security

License

MIT