Prevent destructive operations using Claude Code hooks. Three modes — cautious (warn on dangerous commands), lockdown (restrict edits to one directory), and clear (remove restrictions). Uses PreToolUse matchers for Bash, Edit, and Write.
Three levels of protection against destructive operations during AI coding sessions.
Note: These hooks are skill-scoped — they only activate when you invoke
/safe-mode. The globalpermission-request.jshook in hooks.json provides always-on alerting for dangerous commands. Safe-mode adds opt-in blocking and directory restrictions on top of that.
/safe-mode cautiousIntercepts Bash commands before execution. Warns on dangerous patterns but does not block — the user decides.
Flagged patterns:
| Pattern | Risk |
|---|---|
rm -rf / rm -r | Recursive deletion |
DROP TABLE / DROP DATABASE | SQL data loss |
TRUNCATE | SQL data destruction |
git push --force / git push -f | Remote history rewrite |
git reset --hard | Local history loss |
git clean -f | Untracked file deletion |
git checkout . / git restore . | Discard all changes |
chmod 777 | World-writable permissions |
curl or wget piped to a shell | Piped remote execution |
> /dev/sda / dd if= | Disk-level operations |
:(){ :|:& };: | Fork bombs |
sudo rm | Elevated deletion |
What happens: the hook returns a permission ask, so Claude Code shows you a prompt that names the pattern, for example Safe mode: rm with -r or -f. You approve or reject the command. This prompt appears even in auto mode.
/safe-mode lockdown <path>Restricts Edit and Write operations to a single directory tree. Prevents accidental changes to unrelated code.
How it works:
LOCKDOWN ACTIVE: Edits restricted to src/api/
Blocked: Edit to src/utils/helpers.ts
Reason: File is outside the lockdown path (src/api/)
To edit files outside the lockdown, run: /safe-mode clearUse cases:
Scope: Keyed to the project root. It stays set until /safe-mode clear, and only enforces in sessions where /safe-mode was invoked.
/safe-mode clearRemoves all restrictions for the current session. Both cautious warnings and lockdown restrictions are disabled.
SAFE MODE: All restrictions cleared for this session.Invoking this skill registers one PreToolUse hook for Bash|Edit|Write that runs scripts/safe-mode-guard.js. Skill hooks stay registered for the rest of the session. The guard does nothing until a mode is set.
When the user runs /safe-mode <mode>, run the guard's setter from the project root:
node "${CLAUDE_PLUGIN_ROOT}/scripts/safe-mode-guard.js" set cautious
node "${CLAUDE_PLUGIN_ROOT}/scripts/safe-mode-guard.js" set lockdown src/api/
node "${CLAUDE_PLUGIN_ROOT}/scripts/safe-mode-guard.js" set clearThen report the line the setter prints.
The guard checks tool_input.command against a fixed list of destructive patterns: recursive or forced rm, DROP and TRUNCATE, force-push, hard reset, git clean -f, discarding all changes, chmod 777, piping curl or wget to a shell, disk-level writes, fork bombs, and sudo rm. A match returns permissionDecision: "ask" with the pattern as the reason. No match passes through.
The guard resolves tool_input.file_path against the project root, follows symlinks, and checks that it sits inside the lockdown path. Inside passes through. Outside exits 2, which blocks the edit and tells Claude why.
The mode lives in $TMPDIR/pro-workflow/safe-mode-<hash>.json, keyed by the project root, so two projects never share it:
{ "cautious": true, "lockdownPath": "/Users/dev/project/src/api", "root": "/Users/dev/project" }set clear deletes the file. The file outlives the session, so clear it when you are done; a new session only enforces it again after /safe-mode is invoked, because the hook is skill-scoped.
Cautious and lockdown can run simultaneously:
/safe-mode cautious
/safe-mode lockdown src/api/Now you get:
src/api/ onlyClear removes both.
| Situation | Mode |
|---|---|
| Working on production-adjacent code | Cautious |
| Focused refactoring of one module | Lockdown |
| Unfamiliar codebase, feeling cautious | Cautious |
| Pair programming, limiting AI scope | Lockdown |
| Done with restrictions | Clear |
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