Microsoft SQL Server MCP Server: Zero-Downtime, 24/7 Resilience

Microsoft SQL Server MCP Server

A Model Context Protocol (MCP) server that enables secure interaction with Microsoft SQL Server databases. This server allows AI assistants to list tables, read data, and execute SQL queries through a controlled interface, making database exploration and analysis safer and more structured.

Features

• List available SQL Server tables as resources
• Read table contents
• Execute SQL queries with proper error handling
• Secure database access through environment variables
• Comprehensive logging
• Automatic system dependency installation

Installation

The package will automatically install required system dependencies (like FreeTDS) when installed through MCP:

pip install mssql-mcp-server

Configuration

Set the following environment variables:

MSSQL_SERVER=localhost
MSSQL_USER=your_username
MSSQL_PASSWORD=your_password
MSSQL_DATABASE=your_database

Usage

With Claude Desktop

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "mssql": {
      "command": "uv",
      "args": [
        "--directory", 
        "path/to/mssql_mcp_server",
        "run",
        "mssql_mcp_server"
      ],
      "env": {
        "MSSQL_SERVER": "localhost",
        "MSSQL_USER": "your_username",
        "MSSQL_PASSWORD": "your_password",
        "MSSQL_DATABASE": "your_database"
      }
    }
  }
}

As a standalone server

# Install dependencies
pip install -r requirements.txt

# Run the server
python -m mssql_mcp_server

Development

# Clone the repository
git clone https://github.com/RichardHan/mssql_mcp_server.git
cd mssql_mcp_server

# Create virtual environment
python -m venv venv
source venv/bin/activate  # or `venv\Scripts\activate` on Windows

# Install development dependencies
pip install -r requirements-dev.txt

# Run tests
pytest

Security Considerations

• Never commit environment variables or credentials
• Use a database user with minimal required permissions
• Consider implementing query whitelisting for production use
• Monitor and log all database operations

Security Best Practices

This MCP server requires database access to function. For security:

1. Create a dedicated SQL Server login with minimal permissions
2. Never use sa credentials or administrative accounts
3. Restrict database access to only necessary operations
4. Enable logging for audit purposes
5. Regular security reviews of database access

See SQL Server Security Configuration Guide for detailed instructions on:

• Creating a restricted SQL Server login
• Setting appropriate permissions
• Monitoring database access
• Security best practices

⚠️ IMPORTANT: Always follow the principle of least privilege when configuring database access.

License

MIT License - see LICENSE file for details.

Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request