# Hook Development

> Use when creating, modifying, or debugging Claude Code hooks — PreToolUse, PostToolUse, Stop, SubagentStop, SessionStart, SessionEnd, UserPromptSubmit, PreCompact, Notification. Covers the plugin `hooks/hooks.json` wrapper format vs. the user `settings.json` direct format, matchers, security patterns, `$CLAUDE_PLUGIN_ROOT` portability, lifecycle limitations, and debugging. Trigger on "add a hook", "validate tool use", "block dangerous commands", "enforce completion", "hook-based automation".

- Skill: `kanevry/hook-development-3` (Agent Skill)
- Install (CLI): `npx skillmds@latest add kanevry/hook-development-3`
- Raw SKILL.md: https://api.skillmd.com/api/skills/kanevry/hook-development-3/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- Author: Kanevry (https://skillmd.com/u/kanevry)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/kanevry/hook-development-3

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# hook-development

> **Portable mirror — generated, do not edit.** The canonical skill body lives at
> [`skills/hook-development/SKILL.md`](../../../skills/hook-development/SKILL.md); read that file for the full instructions.
> This mirror carries only agentskills.io-spec-legal frontmatter so harnesses that
> discover skills under `.agents/skills/` can find and route to the skill.
>
> Regenerate with `node scripts/generate-agents-skills.mjs`.