# `Codex.Events.CollabAgentSpawnBegin`
[🔗](https://github.com/nshkrdotcom/codex_sdk/blob/v0.16.1/lib/codex/events.ex#L1226)

Collab event emitted when an agent spawn starts.

# `t`

```elixir
@type t() :: %Codex.Events.CollabAgentSpawnBegin{
  call_id: String.t() | nil,
  model: String.t() | nil,
  prompt: String.t() | nil,
  reasoning_effort: String.t() | atom() | nil,
  sender_thread_id: String.t() | nil
}
```

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*Consult [api-reference.md](api-reference.md) for complete listing*