Function textMessageStartChunk

packages/ai/tests/helpers/processor-harness.ts:32–39

(messageId = 'msg-1')

/** A TEXT_MESSAGE_START chunk for an assistant message. */
export function textMessageStartChunk(messageId = 'msg-1'): StreamChunk {
  return {
    type: EventType.TEXT_MESSAGE_START,
    timestamp: Date.now(),
    messageId,
    role: 'assistant',
  }
}

/** A ui-resource CUSTOM event chunk (MCP Apps). */
export function uiResourceChunk(