Cairn MCP Server

A local-first, open-source harness for organizing your files with an AI agent.

People who work with file organization, knowledge management and local first and want it reachable from Claude, Cursor, VS Code, or another MCP client. The project is written in Python.

VERIFIED ACTIVE

LAST COMMIT 2026-07-29 · ★ 2 · #28 OF 41 MAINTAINED FILESYSTEM · VERIFIED 2026-09-18

MIT · Python servers · how we verify → /methodology

01 · Install Cairn

Claude Code

claude mcp add luckyjackluo-cairn -- uvx cairn-mcp-server

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "luckyjackluo-cairn": {
      "command": "uvx",
      "args": [
        "cairn-mcp-server"
      ]
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as local process (stdio) - runs on your machine with your user's permissions

license MIT - declared in the repository

pypi package cairn-mcp-server - check the name against the project README before installing (PyPI has no namespace ownership)

registry namespace io.github.luckyjackluo is GitHub-verified and matches the repo owner

03 · What Cairn can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

Latest releases

v0.2.0 · 2026-07-17

First coordinated release of all four packages to PyPI. · Highlights · Markdown-native tags. Cairn's tag & metadata layer now reads/writes YAML · frontmatter in .md (and any text) files, not just .uni documents - so…

04 · Who maintains Cairn

Cairn is maintained by luckyjackluo. It's the only MCP server we track from this author; the repo dates to Jul 2026.

05 · Facts

repository: github.com/luckyjackluo/cairn
category: filesystem - ranked #28 of 41 actively-maintained filesystem servers as of 2026-09-18.
release cadence: 1 release in the last 90 days (latest 2026-07-17)
registry: io.github.luckyjackluo/cairn (active, first published 2026-07-17)
packages: pypi:cairn-mcp-server

06 · Cairn FAQ

What is Cairn?

A local-first, open-source harness for organizing your files with an AI agent.

Is Cairn still maintained?

Yes - as of 2026-09-18, its last commit was 2026-07-29 and it shipped 1 release in the last 90 days. We re-verify nightly.

How do I install Cairn?

Run `uvx cairn-mcp-server`. You can also paste the ready-made client config above.

Does Cairn run locally?

Yes - it's a stdio server: it runs on your machine (via uvx) with your user's permissions. Your data stays local unless the server itself calls external APIs.

07 · Alternatives to Cairn

Alternatives to Cairn

Maintained filesystem servers if Cairn isn't the fit.

More filesystem MCP servers · Devtools · Octofs · Pickanagency · OWA Exchange MCP Server · Fs MCP Rs

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