A few smaller tools, each of which behaves differently when an agent is holding it.
Stash
A shelf for unfinished work. git stash puts your changes to tracked files aside and returns your folder to the last commit, and git stash pop brings them back. New files git isn't tracking yet stay where they are unless you add -u.
A stash has no branch and no reminder, and agents don't remember across sessions, so work stashed "to get a clean tree" can sit there unnoticed for ever. Anything you care about belongs in a commit on a branch, which costs no more and shows up in the history.
“If you stash, use git stash push -u -m "why", and pop it before your last step. Run git stash list at the end and show me that it is empty. If it isn't, tell me what is in there.”