Sometimes a change is wrong. Sometimes you only work that out after you accepted it. Neither is a failure — the skill is knowing your way back before you click, not after.
The change isn’t saved until you accept it. So Reject is your first and cheapest undo, and Undo covers most of what gets past it.
The routes, smallest to biggest
Reject the diff. The cheapest undo is the one where nothing happened. The preview pane shows you something you don’t like, you click Reject, and the file is untouched. There’s nothing to undo. This is the entire reason Claude proposes before it writes.
Click Undo. Accepted, then immediately regretted it? The app keeps the originals of the files it touched, so Undo rolls the last change back. No typing, no version control, one click. This covers the common case: you accepted, you looked properly, you changed your mind.
Ask for it in the chat. You can also just say so:
Undo the last change you made to notes.md.Claude reads the conversation, knows exactly what it changed, and proposes the inverse — which you read and accept like any other diff. Best when the change is fresh and small.
Restore from version control. If the folder is tracked in git, restoring a file brings it back to its last saved-and-committed state, wiping out everything since — Claude’s changes and yours. It’s the blunt option, and it works no matter how many turns ago the change happened. You can ask Claude to do this for you in the chat; you don’t need to know the commands.
Picking one
| Situation | Route |
|---|---|
| The diff is still on screen and looks wrong | Reject — it never lands |
| Just accepted, one small change, want it gone | Undo, or ask Claude to revert it |
| Big change, several files, several turns back | Restore from the last commit |
Nothing to memorise. Just notice the shape: the earlier you catch it, the cheaper the undo.
The habit that saves you
One thing turns “back out of this” from a panic into a shrug: save a checkpoint before big changes.
When Claude is about to do something with real reach — a rename across a dozen files, a restructure, anything you couldn’t eyeball in one diff — make sure the current state is committed first. Then if it goes wrong, one restore puts everything back and your earlier work is untouched.
You’ll meet this advice again anywhere version control comes up. It earns the repetition.