Lifecycle Events
The seven events Codex CLI emits and what OMX does at each point.
Codex CLI emits events at fixed points in a session. OMX hooks attach to these events to do their work. Knowing which event fires when lets you trace why OMX intervened at a given moment and slot your own .omx/hooks/*.mjs plugins into the right place.
Events
| Event | Fires when | What OMX does |
|---|---|---|
SessionStart | Codex session initialises | Restore state, seed wiki summary, verify .omx/ is gitignored |
UserPromptSubmit | User sends a prompt | Keyword detection, skill routing, deep-interview input lock |
PreToolUse | Before a tool call executes | Bash safety checks, inline git commit format guard |
PostToolUse | After a tool call completes | Command-not-found guidance, non-zero output review |
Stop | Model finishes a turn | Ralph / autopilot / ultrawork / ultraqa continuation, auto-nudge on stalls |
PreCompact | Context window nears limit | Reserved — wiki compaction deferred to v2 |
Notification | System notification emitted | Routing to Discord / Slack / Telegram via notify-hook |
PreToolUse and PostToolUse currently intercept Bash only. Non-Bash tool interception falls back to runtime paths. See Codex-Native Hooks for the full coverage matrix.
Subscribing to events in a plugin
An example plugin that reacts to post-tool-use events:
// .omx/hooks/my-plugin.mjs
export async function onHookEvent(event, sdk) {
if (event.event !== 'post-tool-use') return;
sdk.log.info('tool finished', event.context);
}The event envelope always includes schema_version, event, timestamp, source (native or derived), and context.