MCP SQL Server

What is MCP SQL Server?

MCP SQL Server is a Model Context Protocol (MCP) server that enables AI assistants like Claude to securely interact with SQL Server databases through local connections. It provides tools for database exploration, query execution, and data analysis via a controlled interface.

How to use MCP SQL Server?

Clone the repository, install dependencies (npm install), configure environment variables (DB_SERVER, DB_NAME, DB_USER, DB_PASSWORD, DB_PORT) in a .env file, then add the server to Claude Desktop’s claude_desktop_config.json with the correct absolute path and environment variables. After restarting Claude Desktop, you can ask questions like “What tables are in my database?” or “Show me the schema of the Users table”.

Key features of MCP SQL Server

• Secure local database access using SQL Authentication
• Schema exploration: discover tables, columns, and relationships
• Query execution with proper error handling
• Built‑in safety controls against harmful operations
• Read‑only query execution by default
• Tools to list stored procedures, indexes, and constraints

Use cases of MCP SQL Server

• Enabling Claude to explore and query a local SQL Server database
• Discovering table structures and relationships without manual inspection
• Executing safe, read‑only SELECT queries through natural language
• Auditing database schema, indexes, and constraints via AI assistance
• Rapidly retrieving top‑ or filtered‑data from production‑like local databases

FAQ from MCP SQL Server

What dependencies does MCP SQL Server require?

Node.js 18.0 or higher, npm, a SQL Server instance, and the Claude Desktop application.

How does MCP SQL Server access the database?

It connects to a local SQL Server using SQL Authentication, configured through environment variables (DB_SERVER, DB_NAME, DB_USER, DB_PASSWORD, DB_PORT). Only localhost connections are accepted.

Is query execution read‑only?

By default, the execute_query tool runs SELECT queries only. For enhanced security, you should configure the database user with read‑only permissions.

How do I configure MCP SQL Server in Claude Desktop?

Edit claude_desktop_config.json found in the Claude Desktop config directory (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\, Linux: ~/.config/Claude/) and add a server entry pointing to node with the absolute path to mcp-server-sql/index.js and the required environment variables.

What security best practices are recommended?

Use a dedicated SQL Server login with minimal required permissions, configure the database user for read‑only access, restrict connections to localhost, and enable SQL Server audit logging to track all queries.