What runs when (the seven events)
Part 1 · PLUGIN STRUCTURE AND ARCHITECTURE · Slide 5 of 60
CLI event hook what it does
────────────────── ─────────────────────── ─────────────────────────
SessionStart session-start.sh banner, laws, the packet
UserPromptSubmit coord-nudge.sh "log this prompt's work"
router.sh "this looks like /verb"
PreToolUse (Agent) spawn-gate.sh refuses unlawful spawns
PreToolUse (Bash) pretool-gate.sh ship gate, shadow guard
SubagentStop agent-ledger.sh receipts every lane
Stop completion-gate.sh "done" must earn itself
PreCompact pre-compact.sh bank before memory shrinks
SessionEnd session-end.sh crash cushion, ledger roll
Every entry declares its own timeout. Every hook fails OPEN
and silent: a broken hook never takes the session down.