Lark Event

# Lark Events

> **Prerequisite:** Read [`../lark-shared/SKILL.md`](../lark-shared/SKILL.md) first for authentication, `--as user/bot` switching, `Permission denied` handling, and safety rules.

## Core commands

| Command | Purpose |
|------|------|
| `lark-cli event list [--json]` | List all subscribable EventKeys |
| `lark-cli event schema <EventKey> [--json]` | Show an EventKey's params and output schema |
| `lark-cli event consume <EventKey> [flags]` | Blocking consume; events → stdout NDJSON |
| `lark-cli event status [--json] [--fail-on-orphan]` | Inspect the local bus daemon status |
| `lark-cli event stop [--all] [--force]` | Stop the bus daemon |


## Common flags

| Flag | Description |
|---|---|
| `--param key=value` / `-p` | Business params (repeatable; comma-separated for multi-value). Unknown keys fail with valid names listed inline |
| `--jq <expr>` | jq expression to filter / transform each event; empty output skips the event |
| `--max-events N` | Exit after N events. Default 0 = unlimited |
| `--timeout D` | Exit after duration D (e.g. `30s`, `2m`). Default 0 = no timeout. Whichever of `--max-events` / `--timeout` fires first wins |
| `--output-dir <dir>` | Write each event as a file (relative paths only; prevents traversal) |
| `--quiet` | Suppress stderr diagnostics. **AI should not use this** — it silences the ready marker |
| `--as user\|bot\|auto` | Identity for the session (see lark-shared) |


## Examples

```bash
# Default: stream every event for the key (no filter, no projection)
lark-cli event consume im.message.receive_v1 --as bot

# Grab one sample event to inspect payload shape
lark-cli event consume im.message.receive_v1 --max-events 1 --timeout 30s --as bot

# Run for 10 minutes then auto-exit
lark-cli event consume im.message.receive_v1 --timeout 10m --as bot

# Consume multiple EventKeys concurrently (one shape per process, no dispatcher)
lark-cli event consume im.message.receive_v1          --as bot > receive.ndjson &
lark-cli event consume im.message.reaction.created_v1 --as bot > reaction.ndjson &
wait

```

## Call flow

1. `lark-cli event list --json` → pick a legal key
2. `lark-cli event schema <key> --json` → read `resolved_output_schema` + `jq_root_path` to determine field paths
3. `lark-cli event consume <key> [--jq '<expr>']` → consume

## Subprocess contract

### Ready marker

`event consume`'s stderr emits a fixed line `[event] ready event_key=<key>`. **Parent processes should block on stderr until this line appears, then start reading stdout.** Do not fall back to `sleep`.

### stdin EOF = graceful exit

`event consume` treats stdin close as a shutdown signal (wired for AI subprocess callers). `< /dev/null` / `nohup` / systemd's default `StandardInput=null` will cause an immediate graceful exit (stderr `reason: signal`). To keep running:

- Feed stdin a source that never EOFs: `< <(tail -f /dev/null)`
- Or run bounded: `--max-events N` / `--timeout D`

### Exit codes & reason

On exit, the last stderr line is `[event] exited — received N event(s) in Xs (reason: ...)`.

| exit code | reason | Trigger |
|---|---|---|
| 0 | `reason: limit` | `--max-events` reached |
| 0 | `reason: timeout` | `--timeout` reached |
| 0 | `reason: signal` | Ctrl+C / SIGTERM / stdin EOF |
| non-0 | `Error: ...` (no `exited` line) | Startup / runtime failure (permissions, network, params, config) |

Orchestrators shou