流式传输

流式传输允许您在代理运行过程中订阅其更新。这对于向最终用户展示进度更新和部分响应非常有用。

要进行流式传输，您可以调用Runner.run_streamed()，这将返回一个RunResultStreaming。调用result.stream_events()会为您提供一个异步流，包含StreamEvent对象，这些对象将在下面进行描述。

原始响应事件

RawResponsesStreamEvent 是从LLM直接传递的原始事件。它们采用OpenAI Responses API格式，这意味着每个事件都有一个类型（如response.created、response.output_text.delta等）和数据。如果您想在生成响应消息时立即将其流式传输给用户，这些事件非常有用。

例如，这将逐个token输出由LLM生成的文本。

import asyncio
from openai.types.responses import ResponseTextDeltaEvent
from agents import Agent, Runner

async def main():
    agent = Agent(
        name="Joker",
        instructions="You are a helpful assistant.",
    )

    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
    async for event in result.stream_events():
        if event.type == "raw_response_event" and isinstance(event.data, ResponseTextDeltaEvent):
            print(event.data.delta, end="", flush=True)


if __name__ == "__main__":
    asyncio.run(main())

运行项目事件和代理事件

RunItemStreamEvent是更高级别的事件。它们会在项目完全生成时通知您。这使您可以在"消息已生成"、"工具已运行"等层级推送进度更新，而不需要针对每个令牌。同样地，AgentUpdatedStreamEvent会在当前代理发生变化时（例如由于交接操作）为您提供更新。

例如，这将忽略原始事件并向用户流式传输更新。

import asyncio
import random
from agents import Agent, ItemHelpers, Runner, function_tool

@function_tool
def how_many_jokes() -> int:
    return random.randint(1, 10)


async def main():
    agent = Agent(
        name="Joker",
        instructions="First call the `how_many_jokes` tool, then tell that many jokes.",
        tools=[how_many_jokes],
    )

    result = Runner.run_streamed(
        agent,
        input="Hello",
    )
    print("=== Run starting ===")

    async for event in result.stream_events():
        # We'll ignore the raw responses event deltas
        if event.type == "raw_response_event":
            continue
        # When the agent updates, print that
        elif event.type == "agent_updated_stream_event":
            print(f"Agent updated: {event.new_agent.name}")
            continue
        # When items are generated, print them
        elif event.type == "run_item_stream_event":
            if event.item.type == "tool_call_item":
                print("-- Tool was called")
            elif event.item.type == "tool_call_output_item":
                print(f"-- Tool output: {event.item.output}")
            elif event.item.type == "message_output_item":
                print(f"-- Message output:\n {ItemHelpers.text_message_output(event.item)}")
            else:
                pass  # Ignore other event types

    print("=== Run complete ===")


if __name__ == "__main__":
    asyncio.run(main())