from google.adk.agents.llm_agent import Agent, BaseAgent
from google.genai import types
from google.adk.agents.context import Context
from google.adk.models.llm_request import LlmRequest
from google.adk.models.llm_response import LlmResponse
from google.adk.agents.callback_context import CallbackContext
from typing import Optional
from google.adk.tools.tool_context import ToolContext
from google.adk.tools.base_tool import BaseTool
from typing import Any
async def before_agent_callback(callback_context: CallbackContext):
print("Before agent callback triggered")
print(callback_context)
async def after_agent_callback(callback_context: CallbackContext):
print("After agent callback triggered")
print(callback_context)
def before_model_callback(callback_context: Context, llm_request: LlmRequest):
print("Before model callback triggered")
print(callback_context)
print(llm_request)
def after_model_callback(callback_context: Context, llm_response: LlmResponse):
print("After model callback triggered")
print(callback_context)
print(llm_response)
def before_tool_callback(tool: BaseTool, args: dict[str, Any], tool_context: ToolContext) -> Optional[dict]:
print("Before tool callback triggered")
print(tool.name, args)
if False:
return {"result": "Tool execution was blocked by before_tool_callback."}
def after_tool_callback(tool: BaseTool, args: dict[str, Any], tool_context: ToolContext, tool_response: dict) -> Optional[dict]:
print("After tool callback triggered")
print(tool.name, args, tool_response)
def get_temperature(city: str):
"""
A dummy tool to get the temperature of a city.
"""
temprature = len(city) * 3 # Dummy temperature based on city name length
return f"The current temperature in {city} is {temprature} degrees Celsius."
root_agent = Agent(
model='gemini-2.5-flash',
name='root_agent',
description='A helpful assistant for user questions.',
before_agent_callback=before_agent_callback,
after_agent_callback=after_agent_callback,
before_model_callback=before_model_callback,
after_model_callback=after_model_callback,
before_tool_callback=before_tool_callback,
after_tool_callback=after_tool_callback,
instruction='You are a weather assistant. Use get_temperature tool to answer user questions about the weather.',
tools=[get_temperature]
)
async def main():
from google.adk.sessions import InMemorySessionService
from google.adk.runners import Runner
session_service = InMemorySessionService()
runner = Runner(
agent=root_agent,
app_name="app",
session_service=session_service,
)
await runner.run_debug("how warm is it in munich?", verbose=True)
if __name__ == "__main__":
import asyncio
import dotenv
dotenv.load_dotenv()
asyncio.run(main())
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