Librarian MCP: Local AI Server for Persistent Context with Documents
What Librarian MCP Does
Librarian MCP is an open-source Model Context Protocol server that plugs into Jan, LM Studio, or Claude Desktop, turning your local chat window into an interactive research assistant. It solves the problem of document collections that are too large for context windows but too private to send to cloud APIs.
Key Features
- Runs 100% locally with Qwen, GLM, Llama, or any local model
- Remembers everything across your entire conversation (persistent context)
- Searches semantically (finds concepts, not just keywords)
- Writes analysis reports to a sandboxed workspace (you review before applying)
- Works on ANY document collection - code repos, research papers, medical records, legal contracts, Obsidian vaults
- Adopts specialist personas - debugging analyst, compliance expert, legal analyst, knowledge synthesizer
Quick Start Installation
Three-step setup:
git clone https://github.com/orangelightening/Librarian.git && cd Librarian && ./install.shCopy the config output to Jan's MCP settings, then open a new chat.
How It Works
Point it at your documents (any format), open Jan/LM Studio/Claude Desktop, and start chatting with your library. The Librarian maintains context across your entire conversation, building increasingly sophisticated understanding as you chat.
Privacy and Security
- No API calls required
- No data leaves your machine
- Write access is sandboxed to /librarian/ only (can't modify your actual documents)
- Described as having 7 security layers
Technical Details
- Chonkie backend (intelligent semantic chunking)
- ChromaDB vector storage
- 14 production tools (search, sync, read, write, execute, etc.)
- Works with: Jan, LM Studio, Claude Desktop, any MCP client
Real-World Use Cases
- Debugging: "Trace why document sync is failing" → Root cause with code paths
- Legal: "Find inconsistent contract clauses" → Risk assessment report
- Medical: "Validate policies against HIPAA" → Compliance audit
- Obsidian: "Find connections across my notes" → Knowledge map
Perfect for: medical records, legal contracts, corporate data, personal knowledge bases.
📖 Read the full source: r/LocalLLaMA
👀 See Also
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