Callimachus MCP Server

Named for Callimachus, who built the first catalogue of the Library of Alexandria. It runs locally over stdio via the published package.

People who work with codex, developer tools and embeddings and want it reachable from Claude, Cursor, VS Code, or another MCP client. The project is written in Rust.

VERIFIED ACTIVE

LAST COMMIT 2026-07-14 · ★ 39 · #87 OF 229 MAINTAINED CODING AGENT · VERIFIED 2026-09-18

AGPL-3.0 · Rust servers · how we verify → /methodology

01 · Install Callimachus

before you install - you'll need

The README does not document required environment variables for a basic install.

Claude Code

claude mcp add betabots-llc-callimachus -- npx -y callimachus-mcp

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "betabots-llc-callimachus": {
      "command": "npx",
      "args": [
        "-y",
        "callimachus-mcp"
      ]
    }
  }
}

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 AGPL-3.0 - declared in the repository

npm package callimachus-mcp - unscoped; check the name against the project README before installing

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

03 · What Callimachus can do

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

Limitations (from the README)

- Cross-platform (macOS / Windows / Linux). The only macOS-only piece left is the "Open in CLI" / "Resume" launchers (they drive Terminal via AppleScript); on Windows/Linux those actions return a "not supported yet" notice - everything else (index, search, chat, export, keychain) works everywhere. - Cline / Roo Code / Kilo Code are editor extensions with no CLI, so they are index-only (searchable, but not relaunchabl

Latest releases

v0.11.0 · 2026-07-10

v0.10.0 · 2026-07-07

v0.9.1 · 2026-06-30

04 · Who maintains Callimachus

callimachus is maintained by betabots-llc. It's the only MCP server we track from this author; the repo dates to Jun 2026.

05 · Facts

repository: github.com/betabots-llc/callimachus
category: coding agent - ranked #87 of 229 actively-maintained coding agent servers as of 2026-09-18.
release cadence: 10+ releases in the last 90 days (latest 2026-07-10)
registry: io.github.BetaBots-LLC/callimachus (active, first published 2026-06-27 · 7 versions)
packages: npm:callimachus-mcp

06 · Callimachus FAQ

What is Callimachus?

Named for Callimachus, who built the first catalogue of the Library of Alexandria. It runs locally over stdio via the published package.

Is Callimachus still maintained?

Yes - as of 2026-09-18, its last commit was 2026-07-14 and it shipped 10+ releases in the last 90 days. We re-verify nightly.

How do I install Callimachus?

Run `npx -y callimachus-mcp`. The README does not document required environment variables for a basic install. You can also paste the ready-made client config above.

Does Callimachus run locally?

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

07 · Alternatives to Callimachus

Alternatives to Callimachus

Maintained coding agent servers if Callimachus isn't the fit.

Pairs well with

Servers that cover what Callimachus doesn't - only shown when the pairing reason fits the companion.

More coding agent MCP servers · Grafyx · Dreamd · My Pi · Afterpaths · Ivygrep

More Rust MCP servers · Bitview · psyXe MCP Server · Bulwark · see all