Python MSSQL MCP Server

A Model Context Protocol server implementation in Python that provides access to Microsoft SQL Server databases. This server enables Language Models to inspect table schemas and execute SQL queries through a standardized interface.

Features

Core Functionality

• Asynchronous operation using Python's asyncio

• Environment-based configuration using python-dotenv

• Comprehensive logging system

• Connection pooling and management via pyodbc

• Error handling and recovery

• FastAPI integration for API endpoints

• Pydantic models for data validation

• MSSQL connection handling with ODBC Driver

Prerequisites

• Python 3.x

• Required Python packages:

  • pyodbc

  • pydantic

  • python-dotenv

  • mcp-server

• ODBC Driver 17 for SQL Server

Installation

Screenshots

The screenshot above demonstrates the server being used with Claude to analyze and visualize SQL data.

Project Structure

Directory Structure Explanation

• src/mssql/ - Main source code directory

  • __init__.py - Package initialization

  • server.py - Main server implementation

• tests/ - Test files directory

  • __init__.py - Test package initialization

  • test_mssql.py - MSSQL functionality tests

  • test_packages.py - Package dependency tests

• .env - Environment configuration file (not in git)

• .env.example - Example environment configuration

• .gitignore - Git ignore rules

• README.md - Project documentation

• requirements.txt - Project dependencies

Configuration

Create a .env file in the project root:

API Implementation Details

Resource Listing

• Lists all available tables in the database

• Returns table names with URIs in the format mssql://<table_name>/data

• Includes table descriptions and MIME types

Resource Reading

• Reads data from specified table

• Accepts URIs in the format mssql://<table_name>/data

• Returns first 100 rows in CSV format

• Includes column headers

SQL Execution

• Executes SQL queries

• Supports both SELECT and modification queries

• Returns results in CSV format for SELECT queries

• Returns affected row count for modification queries

Usage with Claude Desktop

Add to your Claude Desktop configuration:

On MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json On Windows: %APPDATA%/Claude/claude_desktop_config.json

Error Handling

The server implements comprehensive error handling for:

• Database connection failures

• Invalid SQL queries

• Resource access errors

• URI validation

• Tool execution errors

All errors are logged and returned with appropriate error messages.

Security Features

• Environment variable based configuration

• Connection string security

• Result set size limits

• Input validation through Pydantic

• Proper SQL query handling

Contact Information

Amornpan Phornchaicharoen

Feel free to reach out to me if you have any questions about this project or would like to collaborate!

Made with ❤️ by Amornpan Phornchaicharoen

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Amornpan Phornchaicharoen

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

Requirements

Create a requirements.txt file with:

These versions have been tested and verified to work together. The key components are:

• fastapi and uvicorn for the API server

• pydantic for data validation

• pyodbc for SQL Server connectivity

• mcp for Model Context Protocol implementation

• python-dotenv for environment configuration

• anyio for asynchronous I/O support

Acknowledgments

• Microsoft SQL Server team for ODBC drivers

• Python pyodbc maintainers

• Model Context Protocol community

• Contributors to the python-dotenv project