librarian

Librarian is a MCP (Model Context Protocol) server that allows any LLM with a compatible MCP client to query Wikipedia for information. It can be configured to automatically fact-check information without requiring explicit user requests.

It communicates exclusively over Streamable HTTP (MCP spec 2026-07-28).

> *"The only thing that you absolutely have to know is the location of the library."*

>

> — Albert Einstein

Features

• Automatic Fact-Checking: Configure your LLM client to proactively verify factual claims using Wikipedia
• Wikipedia Search: Search for relevant Wikipedia articles
• Page Information: Get detailed information about specific Wikipedia pages
• Page Summaries: Quick summaries of Wikipedia pages
• Page Sections: Get specific sections from Wikipedia pages
• Multi-language Support: Query Wikipedia in different languages

Installation

Prerequisites

• uv package manager installed
• Python 3.13 or higher

Setup

git clone 
cd librarian
uv sync

Running the server

uv run python librarian_server.py

The server starts on `http://0.0.0.0:8000`. The MCP endpoint is available at `/mcp`.

For production deployments behind gunicorn, use the ASGI adapter:

gunicorn librarian_wsgi:app -w 4 -k uvicorn.workers.UvicornWorker --bind 0.0.0.0:8000

Client Configuration

Add this to your MCP client configuration to connect to the server:

{
    "mcpServers": {
        "librarian": {
            "url": "https://your-server-host/mcp"
        }
    }
}

Connect to Claude Code

First, start the server:

uv run python librarian_server.py

Then register it with Claude Code:

claude mcp add librarian -t http http://localhost:8000/mcp

The Wikipedia tools will be available automatically in your next Claude Code session.

Automatic Fact-Checking Setup

To make your LLM client automatically use Wikipedia for fact-checking, start your conversations with:

"Use your Wikipedia tools to automatically fact-check any factual claims in our conversation. Don't wait for me to ask - proactively verify information and provide corrections when needed."

Or use the built-in prompt by referencing: `fact_checking_instructions`

Behavior Examples

Once configured, your LLM client will automatically:

• Verify historical dates and events
• Check biographical information
• Confirm scientific facts and discoveries
• Validate geographical information
• Correct common misconceptions
• Provide source attribution from Wikipedia

Available Tools

1. search_wikipedia_pages: Search for Wikipedia articles on any topic and return the top 5 results with selection information

2. get_wikipedia_page_info: Get comprehensive information about a specific page including content, summary, hyperlinked words, and categories

3. get_wikipedia_page_summary: Get quick summaries of Wikipedia pages with customizable sentence length

4. get_wikipedia_page_sections: Get a list of all sections on a Wikipedia page for large pages where you need specific information

5. get_wikipedia_page_sections_info: Get detailed content for specific sections of a Wikipedia page by title or index

All tools support multi-language Wikipedia queries by specifying the language parameter (default: `"en"`).

Examples

Available Tools

*Screenshot showing the Wikipedia tools available when the MCP server is properly configured*

MCP Servers Configuration

*MCP client showing the librarian server successfully connected and available*

VS Code Integration Example

*Example of using the librarian tools within VS Code with GitHub Copilot*

Migration to MCP 2026-07-28

This project was originally built against the MCP `2025-11-05` spec (SDK v1.x). It has been fully migrated to the MCP `2026-07-28` spec (SDK v2.0.0).

What changed in the spec

The 2026-07-28 release is the most significant MCP revision to date. Its core change is a shift from a stateful, session-based protocol to a stateless, request/response protocol:

• The `initialize`/`initialized` handshake is removed — clients send capabilities on every request via `_meta`
• The `Mcp-Session-Id` header is removed — servers are now load-balancer friendly out of the box
• The WebSocket transport is removed entirely
• The HTTP+SSE transport is deprecated in favour of Streamable HTTP
• A new `server/discover` endpoint is required (handled automatically by the SDK)
• Tool/resource/prompt results are now validated against the protocol schema at decoration time

What was updated in this repo

Updated connection endpoints

The previous WebSocket (`wss://`) and SSE (`/sse`) endpoints are no longer available. All clients connect via the Streamable HTTP endpoint:

{
    "mcpServers": {
        "librarian": {
            "url": "https://your-server-host/mcp"
        }
    }
}

License

This project is open source. Please check the license file for details.