At Google Cloud Next ‘25, last April, Google released Agent Development Kit (ADK) for Python, a flexible and modular framework for developing and deploying AI agents.

Now at Google I/O, a Java version of ADK has been made available! And I’m glad to have had the chance to participate in its launch, via code samples, documentation, and helping shape the API so it’s idiomatic for Java developers.

In this article, my goal is to give you the basis to get started with the ADK framework, in Java, using the Gemini model, and running your first Java agents locally.

In my previous article, I detailed how to build an AI-powered short story generation agent using Java, LangChain4j, Gemini, and Imagen 3, deployed on Cloud Run jobs.

This approach involved writing explicit Java code to orchestrate the entire workflow, defining each step programmatically. This follow-up article explores an alternative, declarative approach using Google Cloud Workflows.

I’ve written extensively on Workflows in the past, so for those AI agents that exhibit a very explicit plan and orchestration, I believe Workflows is also a great approach for such declarative AI agents.

This project demonstrates how to build a fully automated short story generator using Java, LangChain4j, Google Cloud’s Gemini and Imagen 3 models, and a serverless deployment on Cloud Run.

Every night at midnight UTC, a new story is created, complete with AI-generated illustrations, and published via Firebase Hosting. So if you want to read a new story every day, head over to:

→ short-ai-story.web.app ←

The code of this agent is available on Github. So don’t hesitate to check out the code: