How to Keep Claude Code Running With the MacBook Lid Closed

01

Why does a MacBook sleep with the lid closed even when caffeinate is running?

Because closing the lid is not idle sleep, and idle sleep is what caffeinate normally prevents. macOS treats "nothing has happened for a while" and "the lid just closed" as two different reasons to sleep. Apple's documentation for the idle-sleep assertion says it plainly: the system may still sleep for lid close, the Apple menu or low battery.

The caffeinate man page lists five kinds of assertion. -d keeps the display on, -i stops idle system sleep, -m stops idle disk sleep, -u declares the user active, and -s prevents system sleep but is "valid only when system is running on AC power". With no flag it holds an idle-sleep assertion. None of them is documented to cover the lid, and on battery -s does not apply at all.

This catches agent users out because Claude Code already runs a caffeinate while it writes a reply. With the lid open the Mac stays awake and looks protected. Close the lid and it sleeps anyway. While it sleeps nothing runs: the agent stops mid-task, and requests that were in flight can time out. Two commands show what is going on:

# What is holding the Mac awake, and with which assertion
pmset -g assertions

# Is lid sleep switched off? 1 = off, 0 = normal
pmset -g | grep SleepDisabled

02

How do you keep a MacBook awake with the lid closed using pmset?

Run sudo pmset -a disablesleep 1. It turns system sleep off entirely, lid close included, on battery and on power, until you run sudo pmset -a disablesleep 0. It needs your admin password and changes a system-wide setting, not just the current session.

The flag is not in the pmset man page, but it is widely used: pmset -g reports it as SleepDisabled, Amphetamine's Power Protect helper installs a sudo rule for exactly these two commands, and AgentAwake switches the same setting. Check it took effect before you close the lid:

# Before you close the lid
sudo pmset -a disablesleep 1
pmset -g | grep SleepDisabled    # expect: SleepDisabled 1

# When the agent has finished
sudo pmset -a disablesleep 0

03

What are the risks of pmset disablesleep?

The risk is that it stays on. Nothing in macOS turns it back off when the agent finishes, so a Mac you put in a bag after the job is still awake and still drawing power.

On battery it will run until the battery is empty, which also loses whatever was not saved. With the lid shut and the Mac in a bag, the fans have little air to move and nothing in the setting reacts to temperature. And if you forget it, the Mac stays awake through every lid close afterwards, for days if nobody checks.

Each of those is fixable: undo the setting when the command ends, stop at a battery floor, and react to heat. The script in the next section does the first two for free.

04

A safer free version: switch lid sleep off for one command

Wrap the agent in a script that turns lid sleep off, runs it, and turns lid sleep back on however the command ends. First let the three pmset commands run without a password, because sudo forgets your password after a few minutes and the undo at the end of a long job would wait for one with nobody there to type it:

# Once: allow exactly these three pmset commands without a password
sudo visudo -f /etc/sudoers.d/lid-awake
# add this one line, using your short user name (run: whoami)
yourname ALL=(root) NOPASSWD: /usr/bin/pmset -a disablesleep 0, /usr/bin/pmset -a disablesleep 1, /usr/bin/pmset sleepnow

#!/bin/bash
# lid-awake: lid sleep off for one command, back on when it ends
# or when the battery falls to FLOOR %. Usage: lid-awake codex
FLOOR=20
P=/usr/bin/pmset
sudo -n $P -a disablesleep 1 || exit 1
( while sleep 60; do
    b=$(pmset -g batt)
    pct=$(echo "$b" | grep -Eo '[0-9]+%' | head -1 | tr -d %)
    if echo "$b" | grep -q "Battery Power" && [ "$pct" -le "$FLOOR" ]; then
      sudo -n $P -a disablesleep 0 && sudo -n $P sleepnow
      exit
    fi
  done ) &
watcher=$!
disown
restore() {
  kill $watcher 2>/dev/null
  sudo -n $P -a disablesleep 0
  ioreg -r -k AppleClamshellState -d 1 | grep -q '"AppleClamshellState" = Yes' && sudo -n $P sleepnow
}
trap restore EXIT
"$@"

# Install it, then start your agent through it
chmod +x lid-awake
sudo mkdir -p /usr/local/bin && sudo mv lid-awake /usr/local/bin/
lid-awake claude

• Lid sleep comes back when the agent exits, when you press Ctrl-C, and when the terminal window closes.
• On battery, a watcher checks once a minute and sends the Mac to sleep at 20%. Change FLOOR to suit.
• If the lid is still shut when the job ends, pmset sleepnow puts the Mac to sleep instead of leaving it running in the bag.
• It cannot help after a kill -9, a crash of the shell or a power cut. Run pmset -g | grep SleepDisabled if in doubt.
• It watches neither heat nor whether the agent is still working. An agent that sits waiting for your approval keeps the Mac awake until you answer.

05

Does clamshell mode work for AI agents?

Yes, if you are at a desk. Clamshell, or closed-display, mode is the way Apple documents for running a MacBook with the lid shut: connect it to power and to an external display, keyboard and mouse or trackpad, then close the lid and keep working on the external screen. Nothing is changed in the system, so there is nothing to undo.

It does not cover the case most agent users have in mind, which is closing the lid and leaving: on battery, or with nothing plugged in, closing the lid still sleeps the Mac.

06

How does AgentAwake keep agents running with the lid closed?

AgentAwake is a menu bar app from SyncEdge that does the pmset switch for you, only while an agent is working. An agent counts as working when Codex or opencode, once connected, report through their hooks, when a caffeinate runs inside it, as Claude Code does while it replies, or when its own process is busy on the processor. By default it watches claude, codex, gemini, aider and opencode. When none is working it waits a grace period, 2 minutes by default, and lets the Mac sleep.

It adds the safeguards the manual method lacks. On battery the Mac is allowed to sleep at a floor you choose: 10, 15, 20 or 25%. It pauses whenever macOS reports serious heat. It runs the fans: on the default Balanced profile they hold at least 40% while the lid is closed and agents work, and reach full speed at 90 °C. The panel shows "Lid sleep blocked ✓" only after reading the setting back from the system, and a watchdog turns lid sleep back on within 60 seconds if the app stops.

Setup asks for your password once. The sudo rule it installs covers exactly three pmset commands: lid sleep off, lid sleep on, and sleep now. It needs macOS 14 or later on Apple silicon or Intel, works fully for 14 days without a card, then costs $9.99 a year for up to 3 Macs.

AgentAwake: how it works, pricing and download

07

Which method should you use?

Pick by where the Mac will be. At a desk with a monitor, clamshell mode needs nothing new. For one job you will check on, the two pmset commands are enough. If you close the lid and walk away often, use something that turns the setting back on by itself: the lid-awake script above, or AgentAwake if you also want the heat pause, fan control and a watchdog.

With the lid open, none of this is needed: caffeinate -i <command> keeps a long build or test run going until it ends.

AgentAwake vs caffeinate, pmset, Amphetamine and Hold My Lid