This is the model that will be used to extract the structured output.
To provide your own custom system and user prompts for structured output extraction, populate the messages array with your system and user messages. You can specify liquid templating in your system and user messages.
For text extraction, you must reference 'transcript', 'messages', or 'messagesWithConfidence' with the {{}} syntax to access the conversation history.
In structured outputs, {{messages}} includes conversation text and tool calls/results but omits caller transcription-confidence fields. Text extraction can use {{messagesWithConfidence}} when the output needs the original message history with transcription confidence. These variables also apply in structured-output schema descriptions. Audio-targeted (messages-with-audio) extraction ignores custom messages. Stored call artifacts and API messages retain their confidence data.
Between the system or user messages, you must reference a variation of the structured output with the {{}} syntax to access the structured output definition.
i.e.:
{{structuredOutput}}
{{structuredOutput.name}}
{{structuredOutput.description}}
{{structuredOutput.schema}}
If model is not specified, GPT-4.1 will be used by default for extraction, utilizing default system and user prompts.
If messages or required fields are not specified, the default system and user prompts will be used.