custom-hooks

name	custom-hooks
version	1.0.0
description	Create project-specific hook scripts and register them in settings.json. Extends the framework's enforcement layer.
trigger	manual
depends-on	[]
references	[]
disable-model-invocation	true
user-invocable	true
allowed-tools	Read, Glob, Grep, Bash, Edit, Write
argument-hint	<hook-event> "<description>"

---

custom-hooks

Creating a custom hook: $ARGUMENTS

Supported Hook Events

Present available Claude Code hook events:

Event	When It Fires	Can Block?	Input Fields
SessionStart	Once at session start	No	session data
PreToolUse	Before any tool call	Yes (exit 2)	tool_name, tool_input
PostToolUse	After any tool call	No	tool_name, tool_input, tool_output
Stop	When model wants to stop	Yes (exit 2)	last_assistant_message
UserPromptSubmit	When user submits prompt	No	user_prompt
SubagentStop	When a subagent completes	No	last_assistant_message
WorktreeCreate	When a worktree is created	No	—
WorktreeRemove	When a worktree is removed	No	—

Matchers (for PreToolUse and PostToolUse): Filter by tool name — Bash, Edit, Write, Read, Glob, Grep, or combinations with | (e.g., Edit|Write).

1. Understand Requirements

Parse $ARGUMENTS to determine:

• Event type: Which hook event to listen to
• Purpose: What the hook should do
• Blocking vs Advisory: Should it block (exit 2) or just warn (exit 0)?

If unclear, ask:

• "Should this hook block the action or just warn?"
• "Should it fire on specific tools only, or all tools?"
• "Should it run on subagents too?"

2. Generate Hook Script