Getting Started with Google's Agent Developer Kit (ADK): Build Your First AI Agent in Minutes

Himal Joshi — Wed, 29 Apr 2026 07:34:30 +0000

What Dropped at Google Cloud NEXT '26?
Google Cloud NEXT '26 had a ton of announcements — new TPU chips, Gemini Enterprise, AI cybersecurity. But one thing stood out for developers just getting into AI: the Agent Developer Kit (ADK).
No PhD required. Let's build something.

What's an AI Agent vs a Chatbot?
Chatbot: Responds to your message.
Agent: Gets a goal → figures out the steps → calls tools → takes action.

You ask: "Should I pack a jacket for Tokyo?"
Agent checks weather → evaluates the data → gives you a real answer.

That's the difference.

What Is ADK?
ADK is Google Cloud's open-source framework for building, testing, and deploying AI agents. Key points:

Graph-based logic — you define steps explicitly, no "prompt and pray"
Powered by Gemini models
Works with Agent Studio — visual UI for testing
Open source — runs locally, free to start

Build Your First Agent (3 Steps)
Install:
bashpip install google-adk
Authenticate:
bashgcloud auth application-default login
Write the agent (my_agent.py):
pythonfrom google.adk.agents import Agent
from google.adk.tools import Tool

def get_weather(city: str) -> str:
return f"The weather in {city} is sunny and 25°C."

weather_tool = Tool(
name="get_weather",
description="Get the current weather for a given city.",
function=get_weather,
)

agent = Agent(
model="gemini-2.0-flash",
tools=[weather_tool],
system_prompt="You are a helpful travel assistant."
)

print(agent.run("What's the weather in Tokyo? Should I pack a jacket?"))
Run it:
bashpython my_agent.py
The agent calls the tool, reads the result, and answers — on its own.

Why Graph-Based Matters
Old way: prompt the model and hope it follows steps in order.
ADK way: you define the flow explicitly:
[Input] → [Search] → [Summarize] → [Email] → [Done]
Each step is predictable, debuggable, and production-safe.

My Take
ADK forces you to think about agent logic structurally — which makes debugging 10x easier. The local-first setup means zero cloud costs while learning. And the graph approach actually scales to production without rewriting everything.
Best beginner-friendly agent framework I've tried.
Resources:

ADK GitHub
ADK Docs
NEXT '26 Developer Keynote

DEV Community: Himal Joshi

Getting Started with Google's Agent Developer Kit (ADK): Build Your First AI Agent in Minutes