Google Ships ADK for Kotlin 1.0 With On-Device Android Agent Extensions

Google announced the 1.0 general availability of the Agent Development Kit (ADK) for Kotlin on September 9, 2026, in a Developers Blog post by Guillaume Laforge. The release brings the Kotlin toolkit to full feature parity with ADK 1.0 Core while adding Android-first, on-device extensions. The open-source repository at github.com/google/adk-kotlin is licensed under Apache License 2.0.

ADK for Kotlin started as a 0.1 preview aimed at idiomatic agent code for Kotlin, Java, and Android. Version 1.0 is framed as production-ready for both server-side JVM agents and mobile apps that need private on-device inference alongside cloud models.

Core parity and Android extensions

The announcement lists hierarchical multi-agent systems, context compaction for multi-turn chats, human-in-the-loop confirmation flows, long-running and annotation-based tools via @Tool and @Param with KSP compile-time schema generation, session resumability, first-party Java interoperability, and Vertex AI session and memory services. The Kotlin Multiplatform core stays agnostic to model backends, session stores, and memory systems.

Android modules cover on-device agents through LiteRT-LM and ML Kit (beta), hybrid cloud workflows through Firebase AI Logic, and persistence with Room sessions plus AppSearch-indexed memory. Getting started pins com.google.adk:google-adk-kotlin-core:1.0.0 and the matching KSP processor, with optional mlkit-android 1.0.0-beta, litertlm 1.0.0, and firebase-android 1.0.0 artifacts.

Examples in the launch post

Google walks through a database incident-response agent that loads a SKILL.md playbook, calls typed diagnostics tools, and notifies on-call chat, plus an Android financial assistant that pauses on a requireConfirmation fund transfer until the user approves in the UI. Documentation lives at adk.dev, with samples linked from the blog.

Primary sources for this brief are Google’s September 9 Developers Blog announcement, the google/adk-kotlin GitHub repository (Apache 2.0), and adk.dev.