import json
import os
import urllib.request
import urllib.parse
from openai import OpenAI
api_key = os.getenv("OPENAI_API_KEY")
if not api_key:
raise ValueError("OPENAI_API_KEY environment variable not set")
client = OpenAI(api_key=api_key)
SYSTEM_PROMPT = """You are an expert weather forecaster, who speaks in puns.
You have access to two tools:
- get_weather_for_location: use this to get the weather for a specific location
- get_user_location: use this to get the user's location
If a user asks you for the weather, make sure you know the location. If you can tell from the question that they mean wherever they are, use the get_user_location tool to find their location.
"""
TOOLS = [
{
"type": "function",
"function": {
"name": "get_weather_for_location",
"description": "Get weather for a given location name.",
"parameters": {
"type": "object",
"properties": {
"location": {
"type": "string",
"description": "The location to get weather for.",
}
},
"required": ["location"],
},
},
},
{
"type": "function",
"function": {
"name": "get_user_location",
"description": "Retrieve the user's current location from application context.",
"parameters": {
"type": "object",
"properties": {},
"additionalProperties": False,
},
},
},
]
RESPONSE_FORMAT = {
"type": "json_schema",
"json_schema": {
"name": "weather_response",
"strict": True,
"schema": {
"type": "object",
"properties": {
"punny_response": {"type": "string"},
"weather_conditions": {"type": ["string", "null"]},
},
"required": ["punny_response", "weather_conditions"],
"additionalProperties": False,
},
},
}
_WMO_CODES = {
0: "clear sky", 1: "mainly clear", 2: "partly cloudy", 3: "overcast",
45: "foggy", 48: "depositing rime fog",
51: "light drizzle", 53: "moderate drizzle", 55: "dense drizzle",
61: "slight rain", 63: "moderate rain", 65: "heavy rain",
71: "slight snowfall", 73: "moderate snowfall", 75: "heavy snowfall",
80: "slight rain showers", 81: "moderate rain showers", 82: "violent rain showers",
95: "thunderstorm", 96: "thunderstorm with slight hail", 99: "thunderstorm with heavy hail",
}
def get_weather_for_location(location: str) -> str:
geo_url = "https://geocoding-api.open-meteo.com/v1/search?" + urllib.parse.urlencode(
{"name": location, "count": 1}
)
with urllib.request.urlopen(geo_url) as resp:
geo = json.loads(resp.read())
if not geo.get("results"):
return f"Could not find a location named '{location}'."
loc = geo["results"][0]
lat, lon = loc["latitude"], loc["longitude"]
name = loc.get("name", location)
weather_url = "https://api.open-meteo.com/v1/forecast?" + urllib.parse.urlencode({
"latitude": lat,
"longitude": lon,
"current": "temperature_2m,weather_code,wind_speed_10m",
"temperature_unit": "fahrenheit",
"wind_speed_unit": "mph",
})
with urllib.request.urlopen(weather_url) as resp:
weather = json.loads(resp.read())
cur = weather["current"]
condition = _WMO_CODES.get(cur["weather_code"], "unknown conditions")
temp = cur["temperature_2m"]
wind = cur["wind_speed_10m"]
return f"{name}: {condition}, {temp}°F, wind {wind} mph"
def get_user_location(user_id: str) -> str:
return "Miami" if user_id == "1" else "San Francisco"
TOOL_DISPATCH = {
"get_weather_for_location": lambda args, _ctx: get_weather_for_location(args["location"]),
"get_user_location": lambda _args, ctx: get_user_location(ctx["user_id"]),
}
def run_agent(messages: list[dict], context: dict) -> dict:
while True:
response = client.chat.completions.create(
model="gpt-4o",
temperature=0,
messages=messages,
tools=TOOLS,
response_format=RESPONSE_FORMAT,
)
message = response.choices[0].message
if message.tool_calls:
messages.append({
"role": "assistant",
"content": message.content,
"tool_calls": [
{
"id": tc.id,
"type": "function",
"function": {
"name": tc.function.name,
"arguments": tc.function.arguments,
},
}
for tc in message.tool_calls
],
})
for tool_call in message.tool_calls:
fn_name = tool_call.function.name
fn_args = json.loads(tool_call.function.arguments)
tool_fn = TOOL_DISPATCH.get(fn_name)
if tool_fn is None:
raise ValueError(f"Unknown tool: {fn_name}")
result = tool_fn(fn_args, context)
messages.append({
"role": "tool",
"tool_call_id": tool_call.id,
"content": result,
})
continue
messages.append({
"role": "assistant",
"content": message.content,
})
return json.loads(message.content)
# --- Run the agent ---
conversation: list[dict] = [{"role": "system", "content": SYSTEM_PROMPT}]
context = {"user_id": "1"}
# First turn
conversation.append({"role": "user", "content": "what is the weather outside?"})
result = run_agent(conversation, context)
print(result)
# {'punny_response': "Florida is still having a 'sun-derful' day! ...", 'weather_conditions': "It's always sunny in Florida!"}
# Second turn (conversation history is preserved)
conversation.append({"role": "user", "content": "thank you!"})
result = run_agent(conversation, context)
print(json.dumps(result, indent=2))
