This event is the output of audio transcription for user audio written to the
user audio buffer. Transcription begins when the input audio buffer is
committed by the client or server (in server_vad mode). Transcription runs
asynchronously with Response creation, so this event may come before or after
the Response events.

Realtime API models accept audio natively, and thus input transcription is a
separate process run on a separate ASR (Automatic Speech Recognition) model,
currently always whisper-1. Thus the transcript may diverge somewhat from
the model’s interpretation, and should be treated as a rough guide.

Returned when input audio transcription is configured, and a transcription
request for a user message failed. These events are separate from other
error events so that the client can identify the related Item.

Returned when an earlier assistant audio message item is truncated by the
client with a conversation.item.truncate event. This event is used to
synchronize the server’s understanding of the audio with the client’s playback.

This action will truncate the audio and remove the server-side text transcript
to ensure there is no text in the context that hasn’t been heard by the user.

Returned when an error occurs, which could be a client problem or a server
problem. Most errors are recoverable and the session will stay open, we
recommend to implementors to monitor and log error messages by default.

Returned when the input audio buffer is cleared by the client with a
input_audio_buffer.clear event.