session-start-hook
Installation
SKILL.md
Startup Hook Skill for Claude Code
Create SessionStart hooks that install dependencies so tests and linters work in Claude Code sessions (CLI, web, or API).
Hook Basics
Input (via stdin)
{
"session_id": "abc123",
"source": "startup|resume|clear|compact",
"transcript_path": "/path/to/transcript.jsonl",
"permission_mode": "default",
"hook_event_name": "SessionStart",
"cwd": "/workspace/repo"
}