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For real-time agent feedback use case, Agno agents integrate with custom tools and asynchronously handle yielding of events from the custom tool. 

import asyncio
from dataclasses import dataclass
from typing import Optional

from agno.agent import Agent
from agno.models.openai import OpenAIChat
from agno.run.agent import CustomEvent
from agno.tools import tool

# ---------------------------------------------------------------------------
# Create Agent
# ---------------------------------------------------------------------------

# Our custom event, extending the CustomEvent class
@dataclass
class CustomerProfileEvent(CustomEvent):
    """CustomEvent for customer profile."""

    customer_name: Optional[str] = None
    customer_email: Optional[str] = None
    customer_phone: Optional[str] = None


# Our custom tool
@tool()
async def get_customer_profile():
    """Example custom tool that simply yields a custom event."""

    yield CustomerProfileEvent(
        customer_name="John Doe",
        customer_email="john.doe@example.com",
        customer_phone="1234567890",
    )


# Setup an Agent with our custom tool.
agent = Agent(
    model=OpenAIChat(id="gpt-4o"),
    tools=[get_customer_profile],
    instructions="Your task is to retrieve customer profiles for the user.",
)


async def run_agent():
    # Running the Agent: it should call our custom tool and yield the custom event
    async for event in agent.arun(
        "Hello, can you get me the customer profile for customer with ID 123?",
        stream=True,
    ):
        if isinstance(event, CustomEvent):
            print(f"Custom event emitted: {event}")


# ---------------------------------------------------------------------------
# Run Agent
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    asyncio.run(run_agent())

​
Run the Example

# Clone and setup repo
git clone https://github.com/agno-agi/agno.git
cd agno/cookbook/91_tools

# Create and activate virtual environment
./scripts/demo_setup.sh
source .venvs/demo/bin/activate

python custom_tool_events.py
For details, see Custom Tool Events cookbook.