The commit will indeed be created immediately, there's no way to prevent that except for .gitignore I'm aware of. Until you run `jj describe`, it won't have a description.

However, if you don't manually put a branch on it, it'll never get pushed and will stay on your machine only.

You can sit on this personal commit and rebase it on top of any other commit to move around the repo, again and again if you like.