A2UI (a2ui.org) is Google's open-source project (Apache 2.0) for agent-driven interfaces, enabling AI agents to send declarative UI descriptions that clients render natively on web, mobile, and desktop. It uses a streaming JSON format for safe, incremental updates without code execution, supporting multi-agent systems, brand control, and cross-platform consistency with renderers for Angular, Flutter, React, and native.
Key Features
- Secure Declarative UI: Agents send data; clients use pre-approved components to prevent attacks.
- LLM-Friendly: Flat structure for easy generation and progressive rendering.
- Cross-Platform: Renderers for web (React/Angular), mobile/desktop (Flutter/native).
- Interoperable: Open registry for custom components; transports like A2A for agent communication.