Append to specific Draft from outside the application

I want to be able to quickly capture text on my Mac and append it to a specific draft. I typically use Keyboard Maestro for this kind of thing, but I’m comfortable with AppleScript and shell scripting too.

The way I envision this, I’d press a hotkey to trigger a Keyboard Maestro text entry field, and then Keyboard Maestro would take the text I’ve entered and, using scripting or menu actions or some other method, append that text to the draft with a specified UUID.

It seems like there isn’t an AppleScript command to append text to a draft; is there another way?

Shortcuts is probably the best way to do this…Drafts has Shortcuts actions to update existing drafts that can append/prepend/etc., and those can work in the background without having to mess with URL schemes.

This is also something the capture window is set up to do…though that might be more steps that you want.