directory-structure-enforcement-hooks

To enforce directory structure in Claude Code, this Skill applies three-layer hooks that intercept file operations, validate paths against rules, and block invalid writes with specific exit codes to prevent drift.

Claude Code can drift and ignore CLAUDE.md rules. A PreToolUse hook prevents this by intercepting Write and Edit tools, inspecting the file path, and blocking operations with exit code 2 when paths violate structure.

Detect directory drift by running a Stop hook at session end. This hook scans for structural changes caused by mv commands or external processes, always exiting 0 to avoid blocking session termination while reporting deviations.

Yes, PreToolUse hooks can validate file paths and return exit 0 to allow operations, or exit 2 to block them. The Stop hook always exits 0 to avoid blocking the session end during drift detection scans.

The best way to prevent file drift is a three-layer defense: PreToolUse validation for writes, a Stop hook for session-end drift detection, and hooks.json matcher exclusion to avoid conflicts with generic blockers.