MessagePart

type MessagePart =
  | {type: 'text'; content: string}
  | {type: 'reasoning'; content: string}
  | {type: 'tool_call'; id: string; name: string; arguments?: string}
  | {type: 'tool_call_response'; id: string; response?: string}
  | {type: 'file'; file_id: string; mime_type?: string; modality: Modality}
  | {type: 'blob'; content: string; mime_type: string; modality: Modality}
  | {type: 'uri'; uri: string; mime_type?: string; modality: Modality};