Google explains how to build Generative UI apps with A2UI and CopilotKit agents

Google published a walkthrough for building Generative UI apps with its framework-agnostic A2UI (Agent-to-UI) standard and CopilotKit's agent-integration stack. A2UI sends UI as declarative JSON messages rather than executable code, so clients render only components from a trusted catalog, and the same payload works across React, Angular, Lit, SwiftUI, Jetpack Compose and Flutter. The guide shows wiring a Google ADK agent through AG-UI, defining a Zod-validated component catalog, and building bi-directional surfaces where user inputs flow back to the agent for multi-step flows like booking.