Checkpoints

ChatML automatically creates checkpoints as Claude modifies files, giving you the ability to rewind changes at any point.

How Checkpoints Work

• Automatic creation — Checkpoints are created whenever files are modified during a conversation
• Git stash-based — Uses git stash create under the hood for reliable snapshots
• Per-conversation — Checkpoints are scoped to individual conversations
• Metadata tracking — Each checkpoint records the timestamp, message index, and affected files

Rewinding Changes

If Claude takes a wrong turn or you want to undo recent changes:

1. Browse the checkpoint history for the conversation
2. Select the checkpoint you want to revert to
3. ChatML restores the files to that state

This is particularly useful when:

• Claude makes an incorrect refactoring
• You want to try a different approach
• An experiment didn't work out

Checkpoint vs. Git

Checkpoints complement git commits:

• Checkpoints are lightweight, automatic, and conversation-scoped — great for fine-grained undo within a work session
• Git commits are explicit, permanent records — use them to save meaningful progress

You can rewind to a checkpoint and then continue working from that point, without affecting git history.