from typing import AsyncGenerator
from agents import Agent, Runner
from openai.types.responses import ResponseTextDeltaEvent

async def stream_response(agent: Agent, prompt: list[dict] | str) -> AsyncGenerator[str, None]:
    """Stream agent response and update the UI."""
    try:
        result = Runner.run_streamed(agent, input=prompt)
        async for event in result.stream_events():
            if event.type == "raw_response_event" and isinstance(event.data, ResponseTextDeltaEvent):
                yield event.data.delta # <-- sends the next piece of response text
    except Exception as e:
        yield f"⚠️🖨 Error: {e}"