The complete system prompt. Twist-owned — the runtime appends recent thread notes as conversation history and nothing else.
Spoken verbatim to open the conversation. Null to let the agent open.
How many recent notes to supply as history. Null for the default of 20.
TTS voice identifier. Null for Plot's default voice.
Requested cap in seconds. Clamped down to the platform maximum, never up. Null for the platform maximum.
Invoked with the finished ChatSession once the session ends.
Delivered at-least-once: a retry after a transient failure can invoke this callback again for the same session. Write it to be safe to run more than once for the same ChatSession.id.
How a realtime conversation should be run. Returned by the twist's spec callback when the user taps a chat action.