Use This MCP server To

Query DuckDB databases via MCP for real-time data retrieval Create and modify tables in DuckDB through MCP commands Inspect DuckDB database schemas programmatically Enable LLMs to analyze local datasets stored in DuckDB Integrate DuckDB querying into AI workflows using MCP Perform local data analysis with LLM-driven database interaction

README

mcp-server-duckdb

PyPI - Version smithery badge

A Model Context Protocol (MCP) server implementation for DuckDB, providing database interaction capabilities through MCP tools. It would be interesting to have LLM analyze it. DuckDB is suitable for local analysis.

mcp-server-duckdb MCP server

Overview

This server enables interaction with a DuckDB database through the Model Context Protocol, allowing for database operations like querying, table creation, and schema inspection.

Components

Resources

Currently, no custom resources are implemented.

Prompts

Currently, no custom prompts are implemented.

Tools

The server implements the following database interaction tool:

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)

Note

The server provides a single unified query function rather than separate specialized functions, as modern LLMs can generate appropriate SQL for any database operation (SELECT, CREATE TABLE, JOIN, etc.) without requiring separate endpoints.

Note

When the server is running in readonly mode, DuckDB's native readonly protection is enforced. This ensures that the Language Model (LLM) cannot perform any write operations (CREATE, INSERT, UPDATE, DELETE), maintaining data integrity and preventing unintended changes.

Configuration

Required Parameters

db-path (string): Path to the DuckDB database file
- The server will automatically create the database file and parent directories if they don't exist
- If --readonly is specified and the database file doesn't exist, the server will fail to start with an error

Optional Parameters

--readonly: Run server in read-only mode (default: false)
- Description: When this flag is set, the server operates 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 Benefit: Prevents the Language Model (LLM) from performing any write operations, ensuring that the database remains unaltered.
- Reference: For more details on read-only connections in DuckDB, see the DuckDB Python API documentation.
--keep-connection: Re-uses a single DuckDB connection mode (default: false)
- Description: When this flag is set, Re-uses a single DuckDB connection for the entire server lifetime. Enables TEMP objects & slightly faster queries, but can hold an exclusive lock on the file.

Installation

Installing via Smithery

To install DuckDB Server for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install mcp-server-duckdb --client claude

Claude Desktop Integration

Configure the MCP server in Claude Desktop's configuration file:

MacOS

Location: ~/Library/Application Support/Claude/claude_desktop_config.json

Windows

Location: %APPDATA%/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "duckdb": {
      "command": "uvx",
      "args": [
        "mcp-server-duckdb",
        "--db-path",
        "~/mcp-server-duckdb/data/data.db"
      ]
    }
  }
}

Note: ~/mcp-server-duckdb/data/data.db should be replaced with the actual path to the DuckDB database file.

Development

Prerequisites

Python with uv package manager
DuckDB Python package
MCP server dependencies

Debugging

Debugging MCP servers can be challenging due to their stdio-based communication. We recommend using the MCP Inspector for the best debugging experience.

Using MCP Inspector

Install the inspector using npm:

npx @modelcontextprotocol/inspector uv --directory ~/codes/mcp-server-duckdb run mcp-server-duckdb --db-path ~/mcp-server-duckdb/data/data.db

Open the provided URL in your browser to access the debugging interface

The inspector provides visibility into:

Request/response communication
Tool execution
Server state
Error messages

mcp-server-duckdb FAQ

How do I install mcp-server-duckdb?

You can install mcp-server-duckdb via PyPI using 'pip install mcp-server-duckdb'.

Does mcp-server-duckdb support creating new tables in DuckDB?

Yes, it supports table creation and modification through MCP commands.

Can I use mcp-server-duckdb for local data analysis?

Absolutely, DuckDB is optimized for local analytical workloads, and this server enables LLMs to interact with local data efficiently.

Is mcp-server-duckdb compatible with multiple LLM providers?

Yes, it works with any MCP client connected to LLMs like OpenAI, Anthropic Claude, and Google Gemini.

Are there any custom resources implemented in mcp-server-duckdb?

Currently, no custom resources are implemented; it focuses on database interaction capabilities.

How does mcp-server-duckdb handle schema inspection?

It allows querying the database schema to understand table structures and metadata via MCP.

Can mcp-server-duckdb be used in cloud environments?

While DuckDB is optimized for local use, the server can be deployed in cloud environments where local database access is required.

What kind of database operations can I perform with mcp-server-duckdb?

You can perform querying, table creation, schema inspection, and other standard DuckDB operations through MCP.