koog

Koog is a JVM (Java and Kotlin) framework for building predictable, fault-tolerant and enterprise-ready AI agents across all platforms – from backend services to Android and iOS, JVM, and even in-browser environments. Koog is based on our AI products expertise and provides proven solutions for complex LLM and AI problems. Maintained by JetBrains on GitHub, where it has earned 4,444 stars from the community.

It's actively developed around agentframework, agentic-ai, agents, and is a solid reference for anyone building with these tools.