title: "Google ADK for the Battle-Tested Agent Developer" description: "An experienced agent developer evaluates Google's Agent Development Kit (ADK) with hands-on code examples in Python and Java, comparing it honestly against LangGraph and Claude Code. Covers LlmAgent, FunctionTool, LiteLLM model swapping, and the ADK web dev UI." keywords: ["Google ADK", "Agent Development Kit", "multi-agent framework", "LlmAgent", "FunctionTool", "LiteLLM", "Google ADK vs LangGraph", "ADK Java SDK", "ADK tutorial", "Google ADK Python", "ADK multi-agent patterns"] series: "Google ADK Deep Dive" part: 1 date: 2026-03-30 author: "Rick Hightower" ---
Cover image: A battle-tested developer evaluating Google ADK alongside LangGraph and Claude Code agent frameworks
This is Part 1 of a 3-part series on Google ADK.
In Part 1, we build a single agent with tools locally. In Part 2, we orchestrate multi-agent workflows. In Part 3, we deploy to production and connect agents across frameworks via A2A.
Series links:
You've built multi-agent systems in LangGraph. You've orchestrated Claude Code sub-agents. You've wired up MCP tools and debugged token-limit blowouts at 2 AM. Now Google's Agent Development Kit wants your attention.
Fair enough. Let's see what it actually looks like from the inside.
I'll be honest: I was skeptical. Every cloud provider has released an "agent framework" in the last year, and most of them are thin wrappers around prompt templates with a press release attached. But ADK surprised me. It's not perfect, and I have real criticisms, but it's a genuine framework with genuine ideas. Let me show you what I found.
This isn't a getting-started tutorial. You can find those on Google's docs site. This isn't a press release rewrite. You can find those on every tech blog that ran the announcement verbatim. This is what happens when you hand ADK to someone who builds with LangGraph and Claude Code every day and say "go build something real."
By the end of Part 1 you’ll have a single Google ADK agent with tools running locally (Python + Java), with session state set up and ready to be exposed via A2A in Part 3.