Recently I bought a usb-c empty external monitor card to prevent mac from going to sleep. There are many of these external monitor simulators on Amazon.
I still see the laptop go to sleep many times with the external monitor simulator.
The dummy display enables “clamshell mode,” which lets your MacBook stay awake even with the lid closed, provided that it’s also on AC power. If the MacBook is not connected to power, the clamshell mode isn’t activated and it will sleep normally.
Adrafinil simply disables the global sleep without spoofing hardware, and re-enables it once the agent is done working, the temperature is too high, or the battery is low.
The app is built for 26+, as I never tested it on earlier versions. It won’t solve your specific case, though, as it only prevents sleep. It won’t wake it once it’s already sleeping.
Caffeinate is burned into my muscle memory at this point. I attribute that to the realization that you could repeat opt flags. There's something catchy about
Thank goodness. I can’t leave my laptop for a second unattended because my cat loves nothing more than to dance on the keyboard. I’ve need something like this.
Interesting. Kind of similar in purpose, but I created a simple app to schedule and type the "continue" word in my terminal after X time has passed, since I have to wait for my usage to be restored. =)
This is exactly what the app does, except it ties it to agent activity and re-enables sleep once the turn ends, the laptop is close to overheating, the battery is low, or on a timer.
This works great. Only downside is display doesn't turn off when you close the lid. Made a little status bar utility to wrap the disablesleep command and address that downside:
I’ve often wondered about the thermal performance or running a MacBook with the lid closed. One argument is that the reduced surface area from a closed lid increases temperature. Others argue that not running & rendering the display (and thus GPU) generates less heat. I’m not sure who to believe.
I think the same...It happend to me that I just ask Claude to build whatever I need for my personal very specific use case without looking what else it's outhere
Everyone dreams about making the next cool AI tool and doesn't bother checking if someone has already made the same thing years ago without the word "AI" in the description
In order to get the same behavior with Amphetamine you’ll need to:
1. Install it from the AppStore (no brew, no GitHub)
2. Not forget to enable lock on lid close
3. If you ever connect/disconnect power while the lid is closed without the optional “Power Protect” system, the MacBook will sleep. The system is a script and a configuration file making sudo pmset -a disablesleep passwordless.
4. Add hooks to Claude Code configuration that will use Apple Script to start and stop Amphetamine sessions. For Codex you’ll have to make a script that will watch process activity to know when a turn ends.
It’s not like Amphetamine can’t do the same, it’s that this app is made specifically for AI agents and nothing else.
I used to do this 15 years ago to keep listening to music from my laptop (one of the white chiclet ones) in my backpack, can't remember the name of the app I used then.
One caveat, your laptop cannot cool inside a backpack, it will overheat and shut down anyway. This happened to me several times.
It has a setting for thermal cutoff that you can set to something like 60º C. Sleeping will stop heavy work (like a build) before it leads to overheating.
At some point, if you closed the lid and didn't have an external monitor plugged in, macos would put the GPU in power save mode, which would tank local llm performance. Is that not the case any more? There were even small singles you could get which would trick the ps into thinking an external monitor was plugged in
https://apps.apple.com/us/app/amphetamine/id937984704?mt=12
Recently I bought a usb-c empty external monitor card to prevent mac from going to sleep. There are many of these external monitor simulators on Amazon.
I still see the laptop go to sleep many times with the external monitor simulator.
This is the one I bought.
4K 60Hz USB-C Type-C Virtual Display Adapter DDC EDID Dummy Plug Headless Ghost Display Emulator 2K 60hz1080P@120Hz
Adrafinil simply disables the global sleep without spoofing hardware, and re-enables it once the agent is done working, the temperature is too high, or the battery is low.
I will see how this app fits into my specific need.
I have to check this on Mac Sequoia 15.7
For example:
caffeinate -dimsu
That keeps the Mac awake so I can use Claude remotely from phone.
You can also wrap your command as well, but I rarely use it.
caffeinate -dimsu your-agent-command
caffeinate -dimsum
sudo pmset -a disablesleep 1
Reset back:
sudo pmset -a disablesleep 0
https://github.com/narcotic-sh/modafinil
(yes, I know, another *afinil named Mac sleep prevention app? but hey, I was first :P)
It’s not like Amphetamine can’t do the same, it’s that this app is made specifically for AI agents and nothing else.
I used to do this 15 years ago to keep listening to music from my laptop (one of the white chiclet ones) in my backpack, can't remember the name of the app I used then.
One caveat, your laptop cannot cool inside a backpack, it will overheat and shut down anyway. This happened to me several times.
(personally I have Ruby scripts that check activity on "tmux capture-output" for that)
https://ghloc.vercel.app/kageroumado/adrafinil?branch=main
https://github.com/narcotic-sh/modafinil
He's a connoisseur.