JetBrains releases Compose Multiplatform 1.12.0 with AI agent tools

JetBrains has released Compose Multiplatform 1.12.0, introducing several significant updates for developers, including enhanced AI integration and improved resource management.

A key feature is the experimental Model Context Protocol (MCP) server for Compose Hot Reload. This allows AI coding agents to connect directly to running applications. Through this server, agents can trigger reloads, take screenshots, inspect semantic trees, simulate user inputs like clicks and text, and read application logs. This enables AI agents to autonomously verify their own code changes by inspecting the rendered UI and catching runtime exceptions.

For web development, the update introduces automatic font fallback. When an application encounters characters not supported by its current fonts, it will now automatically download the appropriate Noto font subset to render text correctly. This ensures proper display of emojis and various scripts, such as Arabic, Japanese, and Devanagari, without requiring developers to bundle additional fonts.

Additionally, a new experimental v2 API for window and dialog states has been introduced for desktop applications. This API provides more granular control over window positioning and sizing, allowing developers to specify which screen a window appears on and manage state changes more effectively through an asynchronous approach.