Fan Control

Menubar app, CLI, HTTP API, and MCP server for Apple Silicon Macs (M1–M5). Auto (macOS default) or Max (hardware-reported maximum). There is no low/custom RPM path.

Safety

• Writes require root (fand LaunchDaemon). Reads do not.
• Max only — cannot pin fans below the firmware floor.
• TTL dead-man switch (default 15 min, max 2 h) returns to Auto.
• Failsafe: live SoC/package sensors (TC* / Tp*) at 102 °C → Auto. Tf* trip-point keys are ignored.
• API listens on 127.0.0.1:8765 only.
• Process exit / SIGTERM / SIGINT → Auto.
• One writer queue owns every SMC write; reads use a second SMC view, so a busy write can never delay a failsafe check.

States

The menubar shows what the sensors report: OFF (nothing spinning), MAX, 23% (auto), — (no data). OFF is display-only — no user, agent or endpoint can command it. GET /status returns the same value as state, and fanctl status prints it.

This uses undocumented SMC keys. Firmware thermal protection still applies. Use at your own risk.

Install

./scripts/install-app.sh

Open Fan Control. If fand is not running it asks for your password once and installs a LaunchDaemon. After that the helper starts at boot and is already up when the app opens.

Or install the daemon yourself: ./scripts/install.sh.

In the menu: Open at Login. Then Max / Auto.

fanctl status
fanctl max --ttl 900
fanctl auto
curl -s http://127.0.0.1:8765/status

MCP: npx tsx mcp/src/index.ts or npm --prefix mcp install && npm --prefix mcp run build. Tools: get_thermal_status, max_fans, set_fan_auto.

Uninstall: ./scripts/uninstall.sh.

License

MIT. See LICENSE.