Vercel Labs has introduced UI SDK, a library designed to help AI coding agents assemble user interface components. The core package, @ui-sdk/core, contains over 50 UI behaviors, including keyboard navigation, focus management, and drag-and-drop functionality. These behaviors are framework-agnostic, allowing a single definition to be used across React, Vue, Svelte, and Solid applications.
The SDK utilizes primitives defined via definePrimitive, which manage state, APIs, and slots for DOM elements. Developers can implement prebuilt components such as Select, Combobox, Date Picker, and Color Picker. The system includes a bridge created with createAgent(), enabling agents to list components, track state, and execute actions like renaming projects or updating settings.
Installation is managed via npx skills add vercel-labs/ui --skill ui-sdk, which integrates the necessary packages and documentation for agents. For projects without a build step, the SDK provides web.js and web.css files. The library supports WebMCP for registering tools with browsers and includes callback mechanisms to approve or reject agent-initiated changes.
As of November 12, 2026, six packages are available on npm under version 0.1.0-beta.1 and the Apache-2.0 license. The SDK requires specific framework versions, including React 19+, Vue 3.5+, Svelte 5.33+, and Solid 2.0.0-rc.14+. Vercel distinguishes this tool from existing libraries like React Aria or Zag.js by its specific focus on the agent layer, including the skill system and runtime bridge.
