db-schema-explorer-mcp

MCP server for exploring SQL Server database schemas. Exposes two tools over the Model Context Protocol (stdio transport).

The server accepts a SQL Server connection string via environment variable (recommended) or CLI argument. Both Server= and Data Source= style connection strings are supported.

Tools

get_tables

List table names in the database.

| Parameter | Type | Required | Description | |-----------|------|----------|-------------| | nameFilter | string | No | Partial match filter for table names |

get_table_schema

Get detailed schema for a specific table.

| Parameter | Type | Required | Description | |-----------|------|----------|-------------| | tableName | string | Yes | Exact table name to inspect |

Returns columns (name, data type, max length, nullability) and foreign keys (column, referenced table, referenced column, constraint name).

MCP Client Configuration

Claude Desktop

Add to claude_desktop_config.json (located at %APPDATA%\Claude\ on Windows, ~/Library/Application Support/Claude/ on macOS):

{
  "mcpServers": {
    "db-schema-explorer": {
      "command": "npx",
      "args": ["-y", "db-schema-explorer-mcp"],
      "env": {
        "DB_CONNECTION_STRING": "Server=...;Database=...;User Id=...;Password=...;TrustServerCertificate=True"
      }
    }
  }
}

OpenCode

Add to .opencode/mcp.json in your project root:

{
  "mcpServers": {
    "db-schema-explorer": {
      "command": "npx",
      "args": ["-y", "db-schema-explorer-mcp"],
      "env": {
        "DB_CONNECTION_STRING": "Server=...;Database=...;User Id=...;Password=...;TrustServerCertificate=True"
      }
    }
  }
}

Cursor

Add to .cursor/mcp.json in your project root:

{
  "mcpServers": {
    "db-schema-explorer": {
      "command": "npx",
      "args": ["-y", "db-schema-explorer-mcp"],
      "env": {
        "DB_CONNECTION_STRING": "Server=...;Database=...;User Id=...;Password=...;TrustServerCertificate=True"
      }
    }
  }
}

VS Code (GitHub Copilot)

Add to .vscode/mcp.json in your project root:

{
  "servers": {
    "db-schema-explorer": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "db-schema-explorer-mcp"],
      "env": {
        "DB_CONNECTION_STRING": "Server=...;Database=...;User Id=...;Password=...;TrustServerCertificate=True"
      }
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "db-schema-explorer": {
      "command": "npx",
      "args": ["-y", "db-schema-explorer-mcp"],
      "env": {
        "DB_CONNECTION_STRING": "Server=...;Database=...;User Id=...;Password=...;TrustServerCertificate=True"
      }
    }
  }
}

Development

npm install
npm run build
node dist/index.js

Connection string via environment variable

# Linux / macOS
DB_CONNECTION_STRING="Server=localhost;Database=MyDb;User Id=sa;Password=xxx;TrustServerCertificate=True" node dist/index.js

# Windows (cmd)
set "DB_CONNECTION_STRING=Server=localhost;Database=MyDb;User Id=sa;Password=xxx;TrustServerCertificate=True"
node dist/index.js

Connection string via CLI argument

node dist/index.js "Server=localhost;Database=MyDb;User Id=sa;Password=xxx;TrustServerCertificate=True"

Note: On Windows, semicolons in connection strings can cause issues with shell argument parsing. Prefer the environment variable approach.

Testing

1. MCP Inspector (interactive UI)

The easiest way to test. Create an inspector-config.json file:

{
  "mcpServers": {
    "db-schema-explorer": {
      "command": "node",
      "args": ["dist/index.js"],
      "env": {
        "DB_CONNECTION_STRING": "Server=localhost;Database=MyDb;User Id=sa;Password=xxx;TrustServerCertificate=True"
      }
    }
  }
}

Then run:

npx @modelcontextprotocol/inspector --config inspector-config.json --server db-schema-explorer

This opens a browser UI where you can call both tools interactively and see the JSON responses.

2. Raw JSON-RPC (quick smoke test)

echo '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test","version":"1.0.0"}}}' | node dist/index.js "Server=localhost;Database=MyDb;User Id=sa;Password=xxx;TrustServerCertificate=True"

A successful response looks like:

{"result":{"protocolVersion":"2024-11-05","capabilities":{"tools":{"listChanged":true}},"serverInfo":{"name":"db-schema-explorer","version":"1.0.0"}},"jsonrpc":"2.0","id":1}

3. No-database smoke test

node dist/index.js

Should print the usage message and exit with code 1.