# arc hook

Arc agent documentation

Harness hook entrypoints (hook payload JSON on stdin)

[CLI reference index](/arc/docs/reference/cli) · [CLI behavior guide](/arc/docs/guides/cli)

## arc hook

Harness hook entrypoints (hook payload JSON on stdin)

```text
usage: arc hook [-h] [--base-url BASE_URL] {session-start,stop}

positional arguments:
  {session-start,stop}  which harness hook event fired

options:
  -h, --help            show this help message and exit
  --base-url BASE_URL

```

### Argument defaults

| Argument | Required | Default | Choices |
| --- | --- | --- | --- |
| `event` | yes | null | ['session-start', 'stop'] |
| `--base-url` | no | "http://127.0.0.1:6969" | — |