Hook Events Reference

Purpose: Quick reference for all Claude Code hook events

Available Events

Event	When It Fires	Can Block?
`PreToolUse`	Before tool calls	Yes (exit 2)
`PostToolUse`	After tool calls complete	No
`PermissionRequest`	Permission dialog shown	Yes (allow/deny)
`UserPromptSubmit`	User submits prompt	No
`Notification`	Claude sends notification	No
`Stop`	Claude finishes responding	No
`SubagentStop`	Subagent task completes	No
`PreCompact`	Before compact operation	No
`SessionStart`	New/resumed session	No
`SessionEnd`	Session ends	No

Matcher Syntax

"Bash" - Match specific tool
"Edit|Write" - Match multiple tools (OR)
"*" - Match all tools
"" - Match all (for Notification)

Exit Codes

Code	Behavior
0	Success, continue execution
1	Error logged, continue execution
2	Block operation, feed stderr to Claude

Input/Output

Hooks receive JSON via stdin:

{
  "tool_name": "Bash",
  "tool_input": { "command": "ls -la" },
  "session_id": "...",
  "transcript_path": "..."
}

Output to stderr is fed back to Claude when blocking (exit 2).

Related

../concepts/hooks-system.md - Hooks overview
../examples/hooks/ - Hook examples

Reference: https://docs.anthropic.com/en/docs/claude-code/hooks