weather_agent.py
"""
Serve a Weather Specialist over A2A
===================================
Expose a weather Agent on the dedicated topology port. The trip planner calls
this Agent through the official A2A client at the entity-scoped URL.
Prerequisites: OPENAI_API_KEY, OPENWEATHER_API_KEY, and the `agno[a2a]` extra
Run: .venvs/demo/bin/python cookbook/05_agent_os/15_a2a/multi_agent/weather_agent.py
Try: Fetch GET http://127.0.0.1:7782/a2a/agents/weather-agent/.well-known/agent-card.json
"""
from agno.agent import Agent
from agno.db.sqlite import SqliteDb
from agno.models.openai import OpenAIResponses
from agno.os import AgentOS
from agno.tools.openweather import OpenWeatherTools
# ---------------------------------------------------------------------------
# Create Weather Agent
# ---------------------------------------------------------------------------
db = SqliteDb(
id="a2a-weather-db",
db_file="tmp/a2a_weather.db",
)
weather_agent = Agent(
id="weather-agent",
name="Weather Agent",
description="An A2A specialist for current weather conditions.",
model=OpenAIResponses(id="gpt-5.5"),
db=db,
tools=[
OpenWeatherTools(
units="metric",
enable_forecast=False,
enable_air_pollution=False,
enable_geocoding=False,
)
],
instructions=[
"Use get_current_weather for the requested destination.",
"Return the location, temperature, conditions, and one practical note.",
"If the weather service returns an error, report it clearly.",
],
markdown=True,
)
# ---------------------------------------------------------------------------
# Create AgentOS
# ---------------------------------------------------------------------------
agent_os = AgentOS(
id="a2a-weather-os",
description="AgentOS serving the weather specialist.",
agents=[weather_agent],
a2a_interface=True,
)
app = agent_os.get_app()
# ---------------------------------------------------------------------------
# Run Weather AgentOS
# ---------------------------------------------------------------------------
if __name__ == "__main__":
agent_os.serve(app=app, port=7782)
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[a2a,os]" openai requests
3
Export your API keys
export OPENAI_API_KEY="your_openai_api_key_here"
export OPENWEATHER_API_KEY="your_openweather_api_key_here"
$Env:OPENAI_API_KEY="your_openai_api_key_here"
$Env:OPENWEATHER_API_KEY="your_openweather_api_key_here"
4
Run the example
Save the code above as
weather_agent.py, then run:python weather_agent.py