Async Events Streaming

Stream events from a workflow as it runs.

Install dependencies:

uv pip install agno openai sqlalchemy yfinance

Code

async_events_streaming.py

import asyncio
from textwrap import dedent
from typing import AsyncIterator

from agno.agent import Agent
from agno.db.sqlite import SqliteDb
from agno.models.openai import OpenAIResponses
from agno.run.workflow import WorkflowRunOutputEvent, WorkflowRunEvent
from agno.team import Team
from agno.tools.hackernews import HackerNewsTools
from agno.tools.yfinance import YFinanceTools
from agno.workflow.types import StepInput, StepOutput
from agno.workflow.workflow import Workflow

# Define agents
hackernews_agent = Agent(
    name="Hackernews Agent",
    model=OpenAIResponses(id="gpt-5.2"),
    tools=[HackerNewsTools()],
    role="Extract key insights and content from Hackernews posts",
)
finance_agent = Agent(
    name="Finance Agent",
    model=OpenAIResponses(id="gpt-5.2"),
    tools=[YFinanceTools()],
    role="Get stock prices and financial data",
)

writer_agent = Agent(
    name="Writer Agent",
    model=OpenAIResponses(id="gpt-5.2"),
    instructions="Write a blog post on the topic",
)


async def prepare_input_for_web_search(
    step_input: StepInput,
) -> AsyncIterator[StepOutput]:
    """Generator function that yields StepOutput"""
    topic = step_input.input

    # Create proper StepOutput content
    content = dedent(f"""\
        I'm writing a blog post on the topic
        <topic>
        {topic}
        </topic>

        Search the web for atleast 10 articles\
        """)

    # Yield a StepOutput as the final result
    yield StepOutput(content=content)


async def prepare_input_for_writer(step_input: StepInput) -> AsyncIterator[StepOutput]:
    """Generator function that yields StepOutput"""
    topic = step_input.input
    research_team_output = step_input.previous_step_content

    # Create proper StepOutput content
    content = dedent(f"""\
        I'm writing a blog post on the topic:
        <topic>
        {topic}
        </topic>

        Here is information from the web:
        <research_results>
        {research_team_output}
        </research_results>\
        """)

    # Yield a StepOutput as the final result
    yield StepOutput(content=content)


# Define research team for complex analysis
research_team = Team(
    name="Research Team",
    members=[hackernews_agent, finance_agent],
    instructions="Research tech topics from Hackernews and the web",
)


async def main():
    content_creation_workflow = Workflow(
        name="Blog Post Workflow",
        description="Automated blog post creation from Hackernews and the web",
        steps=[
            prepare_input_for_web_search,
            research_team,
            prepare_input_for_writer,
            writer_agent,
        ],
        db=SqliteDb(
            session_table="workflow_session",
            db_file="tmp/workflow.db",
        ),
    )

    resp: AsyncIterator[WorkflowRunOutputEvent] = content_creation_workflow.arun(
        input="AI trends in 2024",
        stream=True,
        stream_events=True,
    )
    async for event in resp:
        if event.event == WorkflowRunEvent.condition_execution_started.value:
            print(event)
            print()
        elif event.event == WorkflowRunEvent.condition_execution_completed.value:
            print(event)
            print()
        elif event.event == WorkflowRunEvent.workflow_started.value:
            print(event)
            print()
        elif event.event == WorkflowRunEvent.step_started.value:
            print(event)
            print()
        elif event.event == WorkflowRunEvent.step_completed.value:
            print(event)
            print()
        elif event.event == WorkflowRunEvent.workflow_completed.value:
            print(event)
            print()


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