koog

Koog is an open-source JetBrains framework designed for building AI agents on the JVM ecosystem, providing a first-class development experience for both Kotlin and Java developers. Its key differentiator is the ability to deploy agents across multiple targets, including JS, WasmJS, Android, and iOS, using Kotlin Multiplatform. Koog is ideal for developers looking to create custom AI agents with a high degree of flexibility and control.

koog is best for . It sits in the Coding category and is a freemium option.

koog is listed as freemium. Check the official website for current, detailed pricing tiers.

koog scored 7.8 out of 10 in 2026, based on six weighted metrics: usefulness, quality, ease of use, value, reliability, and popularity.

Koog offers a unique combination of idiomatic Kotlin DSL and fluent builder-style Java APIs, making it an attractive choice for developers already familiar with these languages. The framework provides a range of advanced features, including history compression, agent persistence, and structured output, which can be used to optimize and enhance the functionality of AI agents. Koog's support for integrations with popular tools and protocols, such as Spring Boot, Ktor, and OpenTelemetry, makes it easy to incorporate into existing development workflows.

Koog's open-source nature and lack of commercial support may be a limitation for some users, particularly those requiring enterprise-level support and maintenance. The framework's steep learning curve, due to its complex architecture and customization options, may deter some developers from adopting it. Koog's focus on the JVM ecosystem may limit its appeal to developers working with other platforms or languages.

koog is a solid, well-rounded option for . Its 7.8/10 score reflects dependable performance in the Coding category.