This repository demonstrates the implementation of the A2UI (Agent-to-UI) protocol for building AI-powered mobile applications. It provides a complete example consisting of: 1) A Python A2A agent server (stock_lookup) that uses Google ADK to process user queries and generate structured UI responses, 2) A Flutter client (GenUIDemo) that connects to the agent via A2A protocol, parses A2UI messages, and renders them as native Flutter UI, and 3) Supporting documentation explaining the A2UI protocol, MCP integration, and AI-assisted engineering practices. The core innovation is the separation of concerns where AI agents generate declarative UI JSON that clients render natively, enabling rich interactions without executing arbitrary code. The repository includes reusable base classes for building A2UI agents that handle schema validation, event processing, and response formatting.