OptionalaudioOptionalidID of a previous conversation item to reference (for item_reference content
types in response.create events). These can reference both client and server
created items.
OptionaltextThe text content, used for input_text and text content types.
OptionaltranscriptThe transcript of the audio, used for input_audio and audio content types.
OptionaltypeThe content type (input_text, input_audio, item_reference, text,
audio).
Base64-encoded audio bytes, used for
input_audiocontent type.