Let Claude Code Work on a Whole Repo Safely

Letting an agent loose on a whole repo is fine, with guardrails. Start with the one that has changed: on Pro, Max and Team plans, interactive terminal sessions now start in auto mode, where a classifier approves actions instead of you. Do not assume it will stop and ask.

1. Check the mode first

The status bar tells you: ⏵⏵ auto mode on versus ⏸ manual mode on. Press Shift+Tab to move to Manual if you want a prompt before each action. Full detail in permissions and allowlists.

2. Work on a branch

git checkout -b ai/feature-x

What it does: gives you a throwaway. If the session goes sideways you delete the branch instead of unpicking commits on main.

3. Plan before multi-file changes

Press Shift+Tab into plan mode, or prefix a single prompt with /plan. Claude reads and proposes; edits stay blocked until you approve. Correcting a plan costs nothing; correcting a bad refactor costs an afternoon.

4. Deny what you never want run

{
  "permissions": {
    "deny": ["Bash(rm *)", "Bash(git push *)", "Read(./.env)", "Read(./.env.*)"]
  }
}

What it does: refuses destructive commands and secret reads regardless of the mode, because deny rules are enforced by Claude Code rather than requested of the model. They also match inside subshells, so echo "$(rm -rf tmp)" is caught too.

5. Review in chunks, and run the tests

Ask for small focused commits rather than one giant change, read diffs before approving, and run tests after each chunk. Give it the map too — a good CLAUDE.md with your commands, conventions and “don’t touch” folders keeps it out of the wrong files.

For genuinely parallel work, isolate it properly with git worktrees rather than two agents in one checkout.

If it goes wrong

/rewind

What it does: opens the rewind menu to restore code and conversation to an earlier checkpoint. Double-tapping Esc on an empty prompt opens the same thing. Press Esc once to stop Claude mid-action the moment it heads somewhere you didn’t intend.

The pattern: check the mode → branch → plan → small reviewed steps → tests. Sensible permissions are what let you move fast without a bad day.

Source: Choose a permission mode.