tool_hook.py
"""Show how to use a tool execution hook, to run logic before and after a tool is called."""
from typing import Any, Callable, Dict
from agno.agent import Agent
from agno.models.openai import OpenAIChat
from agno.tools.websearch import WebSearchTools
from agno.utils.log import logger
# ---------------------------------------------------------------------------
# Create Agent
# ---------------------------------------------------------------------------
def logger_hook(function_name: str, function_call: Callable, arguments: Dict[str, Any]):
# Pre-hook logic: this runs before the tool is called
logger.info(f"Running {function_name} with arguments {arguments}")
# Call the tool
result = function_call(**arguments)
# Post-hook logic: this runs after the tool is called
logger.info(f"Result of {function_name} is {result}")
return result
agent = Agent(
model=OpenAIChat(id="gpt-4o"), tools=[WebSearchTools()], tool_hooks=[logger_hook]
)
# ---------------------------------------------------------------------------
# Run Agent
# ---------------------------------------------------------------------------
if __name__ == "__main__":
agent.print_response("What's happening in the world?", stream=True, markdown=True)
# ---------------------------------------------------------------------------
# Async Variant
# ---------------------------------------------------------------------------
"""Show how to use a tool execution hook with async functions, to run logic before and after a tool is called."""
import asyncio
from inspect import iscoroutinefunction
from typing import Any, Callable, Dict
from agno.agent import Agent
from agno.tools.websearch import WebSearchTools
from agno.utils.log import logger
async def logger_hook(
function_name: str, function_call: Callable, arguments: Dict[str, Any]
):
# Pre-hook logic: this runs before the tool is called
logger.info(f"Running {function_name} with arguments {arguments}")
# Call the tool
if iscoroutinefunction(function_call):
result = await function_call(**arguments)
else:
result = function_call(**arguments)
# Post-hook logic: this runs after the tool is called
logger.info(f"Result of {function_name} is {result}")
return result
agent = Agent(tools=[WebSearchTools()], tool_hooks=[logger_hook])
asyncio.run(agent.aprint_response("What is currently trending on Twitter?"))
Run the Example
1
Set up your virtual environment
uv venv --python 3.12
source .venv/bin/activate
uv venv --python 3.12
.venv\Scripts\activate
2
Install dependencies
uv pip install -U agno ddgs openai
3
Export your OpenAI API key
export OPENAI_API_KEY="your_openai_api_key_here"
$Env:OPENAI_API_KEY="your_openai_api_key_here"
4
Run the example
Save the code above as
tool_hook.py, then run:python tool_hook.py