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mcp/harbor
Claude Desktop

Microsoft SQL Server for Claude Desktop

io.github.alyiox/mcp-mssql

Read-only-by-default SQL Server: schema, parameterized SELECT, execution plans; writes opt-in.

client:Claude Desktop transport:stdio runtime:nuget

Install Microsoft SQL Server in Claude Desktop

~/Library/Application Support/Claude/claude_desktop_config.json · windows: %APPDATA%\Claude\claude_desktop_config.json

Held in this page only — never stored, logged, or sent anywhere but back to your screen. 

{
  "mcpServers": {
    "mcp-mssql": {
      "command": "dnx",
      "args": [
        "Alyio.McpMssql",
        "--yes"
      ],
      "env": {
        "MCPMSSQL_CONNECTION_STRING": "<MCPMSSQL_CONNECTION_STRING>",
        "MCPMSSQL_DESCRIPTION": "<MCPMSSQL_DESCRIPTION>",
        "MCPMSSQL_QUERY_MAX_ROWS": "<MCPMSSQL_QUERY_MAX_ROWS>",
        "MCPMSSQL_QUERY_COMMAND_TIMEOUT_SECONDS": "<MCPMSSQL_QUERY_COMMAND_TIMEOUT_SECONDS>",
        "MCPMSSQL_QUERY_SNAPSHOT_MAX_ROWS": "<MCPMSSQL_QUERY_SNAPSHOT_MAX_ROWS>",
        "MCPMSSQL_QUERY_SNAPSHOT_COMMAND_TIMEOUT_SECONDS": "<MCPMSSQL_QUERY_SNAPSHOT_COMMAND_TIMEOUT_SECONDS>",
        "MCPMSSQL_ANALYZE_COMMAND_TIMEOUT_SECONDS": "<MCPMSSQL_ANALYZE_COMMAND_TIMEOUT_SECONDS>",
        "MCPMSSQL_ALLOW_WRITE": "<MCPMSSQL_ALLOW_WRITE>",
        "MCPMSSQL_WRITE_COMMAND_TIMEOUT_SECONDS": "<MCPMSSQL_WRITE_COMMAND_TIMEOUT_SECONDS>",
        "DOTNET_ENVIRONMENT": "<DOTNET_ENVIRONMENT>"
      }
    }
  }
}

Settings → Developer → Edit Config opens this file. Restart the app after saving. Claude Desktop docs

Microsoft SQL Server in other clients

Microsoft SQL Server MCP server