FastMCP server for Google's langextract library - extract structured information from unstructured text using LLMs
Until 2026-09-26 this record combined several servers published from one repository. The others now have records of their own: iflow-mcp_larsenweigle-langextract-mcp. Checks from before that date include them.
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# LangExtract MCP Server A FastMCP server for Google's [langextract](https://github.com/google/langextract) library. This server enables AI assistants like Claude Code to extract structured information from unstructured text using Large Language Models through a MCP interface. <a href="https://glama.ai/mcp/servers/@larsenweigle/langextract-mcp"> <img width="380" height="200" src="https://glama.ai/mcp/servers/@larsenweigle/langextract-mcp/badge" alt="LangExtract Server MCP server" /> </a> ## Overview LangExtract is a Python library that uses LLMs to extract structured information from text documents while maintaining precise source grounding. This MCP server exposes langextract's capabilities through the Model Context Protocol. The server includes intelligent caching, persistent connections, and server-side credential management to provide optimal performance in long-running environments like Claude Code. ## Quick Setup for Claude Code ### Prerequisites - Claude Code installed and configured - Google Gemini API key ([Get one here](https://aistudio.google.com/app/apikey)) - Python 3.10 or higher ### Installation Install directly into Claude Code using the built-in MCP management: ```bash claude mcp add langextract-mcp -e LANGEXTRACT_API_KEY=your-gemini-api-key -- uv run --with fastmcp fastmcp run src/langextract_mcp/server.py ``` The server will automatically start and integrate with Claude Code. No additional configuration is required. ### Verification After installation, verify the integration entering in Claude Code: ``` /mcp ``` You should see output indicating the server is running and can enter the server to see its tool contents. ## Available Tools The server provides the following tools for text extraction workflows: **Core Extraction** - `extract_from_text` - Extract structured information from provided text - `extract_from_url` - Extract information from web content - `save_extraction_results` - Save results to JSONL format - `generate_v…
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