Only turn end and the moments needing the user should signal. Any other
event reaching the hook, such as agent_completed or auth_success, now
exits without emitting, so a subagent finishing rings nothing even if the
Notification matcher is ignored.
The toast body showed Claude's own message when present and the raw
notification_type otherwise, so permission_prompt and idle_prompt reached
the user as snake_case. Map every event the matcher covers to a readable
label, and keep Claude's message as a suffix when it adds detail.
Notification matcher covers input-needed events only; end of turn had no
signal but idle_prompt, ~60s late. Wire notify-attention.sh on Stop too,
branching on hook_event_name for the message. Signal only: returns
terminalSequence + suppressOutput, never blocks (guard vs BDR-083).
Header documents both client-side prerequisites found in BLK-020.
Notification hook (permission_prompt|idle_prompt|agent_needs_input|
elicitation_*) returns BEL x2 + OSC 777 via the terminalSequence JSON
field (hooks have no controlling TTY). Client side over Remote-SSH:
VS Code accessibility.signals.terminalBell sound:on for the beep,
wenbopan.vscode-terminal-osc-notifier extension for the Windows toast.
Bastien Chanot