Travel Planner with Weather and Flight Lookup – Agent with Tools¶

Demonstrates attaching function tools to an agent. The scenario: a travel planning assistant that can look up weather forecasts and search for flights to help users plan trips.

Tip

What you’ll learn How to attach tools to an agent using the fluent API.

Source: 02_agent_with_tools.py

adk-fluent

from adk_fluent import Agent

agent_fluent = (
    Agent("travel_planner")
    .model("gemini-2.5-flash")
    .instruct(
        "You are a travel planning assistant. Help users plan trips by "
        "checking weather forecasts and searching for flights. Always "
        "check the weather at the destination before recommending flights."
    )
    .tool(check_weather)
    .tool(search_flights)
    .build()
)

Native ADK

from google.adk.agents.llm_agent import LlmAgent


def check_weather(city: str, date: str) -> str:
    """Check the weather forecast for a city on a given date."""
    return f"Forecast for {city} on {date}: 24C, partly cloudy"


def search_flights(origin: str, destination: str, date: str) -> str:
    """Search available flights between two cities on a date."""
    return f"Found 3 flights from {origin} to {destination} on {date}, starting at $299"


agent_native = LlmAgent(
    name="travel_planner",
    model="gemini-2.5-flash",
    instruction=(
        "You are a travel planning assistant. Help users plan trips by "
        "checking weather forecasts and searching for flights. Always "
        "check the weather at the destination before recommending flights."
    ),
    tools=[check_weather, search_flights],
)

Equivalence¶

assert type(agent_native) == type(agent_fluent)
assert agent_native.name == agent_fluent.name
assert len(agent_fluent.tools) == 2

# --- T Module equivalent ---
# T module provides composable tool chains as an alternative to individual .tool() calls
from adk_fluent._tools import T
from google.adk.tools.function_tool import FunctionTool

travel_t = (
    Agent("travel_planner_t")
    .model("gemini-2.5-flash")
    .instruct("Help users plan trips.")
    .tools(T.fn(check_weather) | T.fn(search_flights))
)
ir_t = travel_t.to_ir()
assert len(ir_t.tools) == 2
assert isinstance(ir_t.tools[0], FunctionTool)
assert isinstance(ir_t.tools[1], FunctionTool)