MCP Server Duckdb

🚀 mcp-server-duckdb

A Model Context Protocol (MCP) server implemented for DuckDB, providing the ability to interact with the database through MCP tools. DuckDB is well-suited for local analysis.

🚀 Quick Start

The mcp-server-duckdb allows users to interact with DuckDB databases via the Model Context Protocol (MCP), enabling database operations such as querying, table creation, and schema inspection.

✨ Features

Resources

Currently, no custom resources are implemented.

Prompts

Currently, no custom prompts are implemented.

Tools

The server implements the following database interaction tools:

• query: Execute any SQL query on the DuckDB database
  • Input: query (string) - Any valid DuckDB SQL statement
  • Output: Query results as text (or success message for operations like CREATE/INSERT)

⚠️ Important Note

The server provides a unified query function instead of separate specialized functions because modern large language models (LLMs) can generate appropriate SQL statements for any database operation (e.g., SELECT, CREATE TABLE, JOIN, etc.) without the need to specify endpoints separately.

⚠️ Important Note

When the server runs in read-only mode, DuckDB's built-in read-only protection is enabled. This means that the language model (LLM) cannot perform any write operations (e.g., CREATE, INSERT, UPDATE, DELETE), thus maintaining data integrity and preventing accidental changes.

📚 Documentation

Configuration

Required Parameters

• db-path (string): The path to the DuckDB database file
  • The server will automatically create the database file and its parent directory if they do not exist
  • If --readonly is specified and the database file does not exist, the server will not start and will display an error

Optional Parameters

• --readonly: Run the server in read-only mode
  • Description: When this flag is set, the server will run in read-only mode. This means:
    • The DuckDB database will be opened with read_only=True, preventing any write operations.
    • If the specified database file does not exist, it will not be created.
    • Security Advantage: Prevents the language model (LLM) from performing any write operations, ensuring data security
  • Reference: DuckDB Documentation

Installation

Install via the following command:

uvx add mcp-server-duckdb

When integrating on Claude Desktop, add the following to ~/.config/claude.yaml:

mcp:
  servers:
    - duckdb:
        class_path: mcp_server_duckdb.DuckDBMCPHandler

Usage

When using on Claude Desktop, you can run it via the following command:

uvx serve --port 12345 duckdb:mcp-server-duckdb

Then configure the MCP endpoint in Claude Desktop as http://localhost:12345

Debugging

Start the debugging server via the following command:

uvx debug duckdb:mcp-server-duckdb

The debugger provides the following features:

• Visibility of request/response communication
• Tracking of tool execution
• Server status monitoring
• Error message display