Build Hook Command

Create a new Claude Code hook for lifecycle automation.

Workflow

1. Invoke hook-builder reference for current patterns:

   • Read skills/claude-code-meta/references/hook-builder.md
   • Get: lifecycle events, matcher syntax, hook types

2. Extract requirements:

   • What event to hook? (PreToolUse, PostToolUse, SessionStart, etc.)
   • What should trigger it? (matcher pattern)
   • What should it do? (prompt, command, or skip)

3. Plan hook:

   • Choose lifecycle event
   • Design matcher (tool pattern, context, etc.)
   • Determine action type

4. Add to plugin.json:

   {
     "hooks": {
       "PreToolUse": [
         {
           "matcher": "Write|Edit",
           "hooks": [
             {
               "type": "prompt",
               "prompt": "Reminder: Check quality gates before proceeding"
             }
           ]
         }
       ]
     }
   }
   

5. Test hook:

   • Trigger the lifecycle event
   • Verify matcher catches correctly
   • Confirm action executes

6. Document:

   • Add comment above hook in plugin.json
   • Document in plugin CHANGELOG
   • Note in README if user-visible

7. Validate:

   • Hook syntax valid JSON
   • Matcher pattern tested
   • Action type appropriate (prompt/command/skip)
   • No infinite loops or recursion

8. Return:

   • Hook event type
   • Matcher pattern
   • Action configured

Criteria

Lifecycle Events:

• PreToolUse - before tool execution (can block)
• PostToolUse - after tool completion
• SessionStart - at session initialization
• SessionEnd - at session termination
• PreCompact - before conversation compaction

Matcher Patterns:

• Tool names: "Read|Write|Edit"
• Regex patterns: ".*\.ts$"
• Context checks: specific file paths

Action Types:

• prompt - inject text into conversation
• command - execute shell command
• skip - prevent tool execution (PreToolUse only)

Best Practices:

• Hooks are deterministic (always run when matched)
• Use for guaranteed behavior, not contextual decisions
• Avoid hooks for complex logic (use skills instead)

See Also

• Full patterns: skills/claude-code-meta/references/hook-builder.md
• Hook guide: https://code.claude.com/docs/hooks-guide