Claude Code

#Why Checkpoints Matter

Other AI tools generate code and hope you catch mistakes. Claude Code shows you exactly what’s about to change before it happens—then asks for permission.

This “checkpoint workflow” is what makes Claude Code safe for serious refactoring work.

#How Checkpoints Work

#Step 1: Request a Change

Refactor the UserService to use dependency injection

#Step 2: Review the Plan

Claude Code responds with its understanding:

• Files it will modify
• The approach it’s taking
• Potential risks or considerations

You can adjust the plan before any changes happen.

#Step 3: Preview Diffs

For each file, you see a visual diff:

- constructor() {
-   this.db = new Database();
- }
+ constructor(private db: Database) {}

Review each change. Ask questions. Request modifications.

#Step 4: Approve or Reject

Only after you approve does Claude Code apply changes. You stay in control.

#Tips for Effective Checkpoint Use

#1. Review Diffs Thoroughly

Don’t just glance. The AI occasionally makes logical errors that look plausible. Check that:

• Variable names are consistent
• Logic flows correctly
• Edge cases are handled

#2. Ask “Why” Questions

Claude Code excels at explanation. If a change seems odd:

Why did you choose to extract this into a separate function?

You’ll get a reasoned answer that helps you evaluate the decision.

#3. Iterate Before Approving

You can modify the plan multiple times:

Actually, let's also add error handling for network failures

Claude Code adjusts the diff without losing previous work.

#4. Use Partial Approvals

You can approve some files while rejecting others:

Apply the changes to user-service.ts but skip the tests for now

#Pro Tip

For large refactors, break them into smaller checkpoints. Instead of “refactor entire auth system,” do “refactor auth types” → “refactor auth service” → “refactor auth middleware”. Each checkpoint is safer and easier to review.