Decaf

The caffeinate command as a smart menu bar app.

Keeps your Mac awake while Claude Code is actually working — and lets it sleep the moment the agent is done, or is only waiting on you.

Every other keep-awake app is a switch you have to remember to turn off. This one puts itself down.

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brew install --cask AlanY1an/decaf/decaf

Or download the DMG from the latest release. Requires macOS 14 or later.

It works out of the box. On first launch it offers to install hooks into Claude Code, which sharpens detection from about five minutes to the exact turn — one click, optional, and reversible.

• Stays awake while a turn is running, and lets go a few minutes after it finishes
• Lets your Mac sleep when the agent is waiting on you — an idle prompt is not work
• Doesn't give up on a long, quiet job — a 20-minute build looks idle and isn't
• Survives self-paced loops — when an agent schedules its own wake-up, Decaf waits with it instead of sleeping through the gap
• Works as a plain switch too — hold for 30 minutes, until 6 PM, or indefinitely
• Gets out of the way — Low Power Mode, fast user switching and a low battery all release it; closing the lid always wins
• Shows token usage and rate limits, every number labelled official or estimated
• Codex and opencode
• Scheduled time windows ("keep awake 9–6 on weekdays")
• Automatic updates
• Clamshell mode, with a loud warning

_{Four menu bar states. The Mac sleeps normally in the first one.}

Decaf watches ~/.claude. That deserves a straight answer.

• It makes no network requests. No telemetry, no analytics, not even an update check.
• It never reads your conversation. It reads timestamps, ids and token counts — never a prompt, never a reply. That limit is enforced by the code's structure and pinned by tests, not by good intentions.
• It writes only to its own folder, plus its hook entries in ~/.claude/settings.json if you let it. Both are reversible from Settings.

You see exactly what it will write before it writes anything:

Six, and no more.

Why "Decaf" if it does caffeinate's job? Because the job is knowing when to stop. Everything in this category is named for the stimulant, and every one of them is a switch you have to remember to turn off. The subtitle keeps the word caffeinate because that is the command you already know — but the app deliberately does not share the name, so it can never shadow /usr/bin/caffeinate.

Does it read my conversations? No. It reads timestamps, session ids and token counters, and nothing else — see Privacy above. The parsers are closed enums with tests pinning their fields, so widening them is a failing build rather than something a code review has to catch.

How is this different from KeepingYouAwake or Amphetamine? Those are switches, and good ones. Decaf decides. If a switch is what you want, KeepingYouAwake is well maintained and you should use it. (Decaf is also that switch when you want it to be.)

Do I have to install the hooks? No. Without them it watches for file activity instead — roughly five minutes of resolution rather than instant — and the menu tells you which one is running.

Does it work with the lid closed? No. Clamshell keep-awake needs a privileged helper and carries a real heat risk on a closed laptop. It is on the roadmap and will ship with a warning you cannot miss, or not at all.

Will it drain my battery? It can only prevent sleep, and it stops below 20%. The default lets your Mac sleep whenever the agent isn't working — for most people that is less awake time than a switch they forgot about.

Why isn't it on the Mac App Store? The sandbox makes what Decaf does impossible, not merely inconvenient. Permanent, not a backlog item.

How do I uninstall it? brew uninstall --cask AlanY1an/decaf/decaf, or drag it out of Applications. If you installed hooks, use Settings → Agents → Uninstall Hooks first — it removes Decaf's entries and leaves everything else untouched. Power assertions die with the process, so quitting or deleting Decaf can never leave your Mac unable to sleep.

git clone https://github.com/AlanY1an/decaf.git
cd decaf
Scripts/bootstrap.sh
swift test --package-path Core

How it all works: docs/architecture.md.

MIT. See LICENSE.