Write the sample application

To write an application in Python:

1. Create a new parent directory namedparent_folder and change directory into it:

   mkdirparent_foldercdparent_folder

2. In theparent_folder directory, create a new subdirectory namedmulti_tool_agentand change directory into it:

   mkdirmulti_tool_agentcdmulti_tool_agent

3. Create an__init__.py file to import the agent:

   from.importagent

4. Create anagent.py file to define the agent for answering questionsabout the time and weather in a specified city:

   importdatetimefromzoneinfoimportZoneInfofromgoogle.adk.agentsimportAgentdefget_weather(city:str)->dict:"""Retrieves the current weather report for a specified city.    Args:        city (str): The name of the city for which to retrieve the weather report.    Returns:        dict: status and result or error msg.    """ifcity.lower()=="new york":return{"status":"success","report":("The weather in New York is sunny with a temperature of 25 degrees"" Celsius (77 degrees Fahrenheit)."),}else:return{"status":"error","error_message":f"Weather information for '{city}' is not available.",}defget_current_time(city:str)->dict:"""Returns the current time in a specified city.    Args:        city (str): The name of the city for which to retrieve the current time.    Returns:        dict: status and result or error msg.    """ifcity.lower()=="new york":tz_identifier="America/New_York"else:return{"status":"error","error_message":(f"Sorry, I don't have timezone information for{city}."),}tz=ZoneInfo(tz_identifier)now=datetime.datetime.now(tz)report=(f'The current time in{city} is{now.strftime("%Y-%m-%d %H:%M:%S %Z%z")}')return{"status":"success","report":report}root_agent=Agent(name="weather_time_agent",model="gemini-2.0-flash",description=("Agent to answer questions about the time and weather in a city."),instruction=("You are a helpful agent who can answer user questions about the time and weather in a city."),tools=[get_weather,get_current_time],)

5. Create a.env file and add the following variables:

   GOOGLE_GENAI_USE_VERTEXAI=TRUEGOOGLE_CLOUD_PROJECT=PROJECT_IDGOOGLE_CLOUD_LOCATION=REGION

   Replace the following:

   • PROJECT_ID: the Google Cloud project ID.
   • REGION: the region you plan to deploy your service in.

6. Navigate to the parent folder directoryparent_folder, and create arequirements.txt fileto add thegoogle-adk dependency:

   google-adk

   Your source project includes the following structure:

   parent_folder/├── requirements.txt└── multi_tool_agent/    ├── __init__.py    ├── agent.py    └── .env

Your app is finished and ready to be deployed.

Deploy to Cloud Run from source

Deploy from source automatically builds a container image from source codeand deploys it.

1. In your source code directory (parent_folder), deploy to Cloud Run using thefollowing command:

   gcloudrundeploy--source.

   1. When you are prompted for the service name, press Enter to accept thedefault name, for exampleweather-agent.

   2. If you are prompted to enable additional APIs on the project,for example, the Artifact Registry API, respond by pressingy.

   3. When you are prompted for region: select theregionof your choice, for exampleeurope-west1.

   4. If you are prompted to create a repository in the specified region, respond by pressingy.

   5. If you are prompted toallow public access:respondy. You might not see this prompt if there is a domainrestriction organization policy that prevents it; for more details see theBefore you begin section.

   Then wait a few moments until the deployment is complete. On success, thecommand line displays the service URL. Navigate to/list-apps from your service URL. For example,https://weather-agent-123456789101.us-central1.run.app/list-apps.

Run your agent

To query the ADK agent, run the following curl commands:

1. To get the list of apps, run the following command:

   curl -X GETSERVICE_URL/list-apps

   ReplaceSERVICE_URL with the URL of your deployed service.

2. To start a session, run the following command:

   curl -X POSTSERVICE_URL/apps/multi_tool_agent/users/u_123/sessions/s_123 -H "Content-Type: application/json" -d '{"key1": "value1", "key2": 42}'

3. To query the agent, run the following command:

   curl -X POSTSERVICE_URL/run \-H "Content-Type: application/json" \-d "{\"appName\": \"multi_tool_agent\",\"userId\": \"u_123\",\"sessionId\": \"s_123\",\"newMessage\": { \"role\": \"user\", \"parts\": [{ \"text\": \"What's the weather in New York today?\" }]}}"

The agent returns the weather information in the results of your query.

For more information and examples about the supported curl commands, seeUse the API Server in ADK documentation.