Caelune — Claude Code MCP server: what it does, how to install
Windows-based local retrieval engine for Markdown notes, Logseq data, and PDFs. It equips AI clients with private search tools without exposing raw files online.
Open on GitHubWhat Caelune does
Caelune links exact text matching via SQLite FTS5 with vector similarity through LanceDB and BAAI/bge-m3. It handles regular Markdown files alongside Logseq embeds and block properties. An extension pipeline extracts text from PDF documents and formats handled by Apache Tika, with optional reranking via BAAI/bge-reranker-v2-m3.
The MCP server operates strictly read-only. It exposes two tools for inspection and queries, but cannot generate or alter indexes on its own. You must assemble your initial knowledge base inside the 64-bit Windows desktop application first.
A background watcher detects file changes and schedules incremental updates inside disposable worker processes. Retrieval runs either on CPU or NVIDIA CUDA hardware, with automatic fallbacks whenever system RAM or GPU memory gets low.
What it helps with
- retrieve factual snippets from local Markdown and Logseq vaults
- query private PDF documents without third-party cloud uploads
- feed verified source citations into AI coding sessions
- sync modified desktop notes into the search index in the background
Example prompts for the agent
- Look up our deployment checklist in my local Logseq notes
- Find references to database schemas inside the archived PDF files
- Search my private knowledge base for notes on API error handling
How to install Caelune
Install
The MCP registry has no launch command for it: see the repository README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Caelune
What is Caelune?
It is a local-first search system combining SQLite FTS5 text matching with LanceDB vectors. It indexes Markdown, Logseq, and PDF files on 64-bit Windows so AI assistants can retrieve private notes securely.
How to install Caelune for Claude Code?
Download the WIN-EXE package from GitHub releases, run Caelune.exe, and index your source directories. Next, extract the MCP-...-win64.zip release and add its executable path under the stdio settings in your Claude Code configuration.
Can Claude Code build or modify the knowledge index?
No. The MCP server provides read-only inspection and search tools. Generating the index, downloading models, and editing data roots require the Windows desktop application.
