A2UI - Google's open source declarative protocol for Agent-driven user interaction interfaces

What is A2UI?

A2UI (Agent-to-User Interface) is Google's open source Agent-driven interface protocol that solves the problem of generating complex interactive interfaces for AI agents. Through a declarative JSON format, the AI agent describes the structure of the user interface, and the client application (such as Flutter, Angular, etc.) will convert these descriptions into native components to achieve cross-platform compatibility and dynamic updating.The core advantage of A2UI is its non-executable code characteristics, all UI descriptions are static data, do not execute the code, so as to avoid the security risks of the LLM generated code. The core advantage of A2UI is its non-executable code feature. It supports progressive rendering, adapting to the real-time interaction requirements of dialog scenarios, and is framework-independent, so that the same JSON configuration can be rendered on different platforms. The same JSON configuration can be rendered on different platforms. Forms, maps, and other components can be dynamically generated according to the context of the dialog. For example, when ordering food, AI can directly pop-up interface with date selector to avoid tedious Q&A. The project has been integrated into the Gemini 3 model , you can quickly experience the restaurant booking through GitHub and other demo cases .

Features of A2UI

• Declarative JSON format: A2UI uses the JSON format to describe the user interface. The AI agent defines the UI structure in this format, and the client application renders it as the actual interface, realizing a concise and easy-to-generate UI description.
• Non-executable code design: All UI descriptions are static data without code execution, avoiding the security risks that may be brought by LLM generated code and ensuring the security of the interface generation process.
• Progressive rendering support: A2UI supports incremental update of the interface, which is suitable for real-time interactions in dialog scenarios, and is able to gradually render the interface according to user inputs to improve the smoothness of interactions.
• Cross-platform compatibility: The same JSON configuration can be rendered on different platforms such as Web, mobile, etc. It supports multiple front-end frameworks (e.g., Flutter, Angular, Lit, etc.) and realizes a consistent user experience across multiple platforms.
• safety first: The client application maintains a "catalog" and is only allowed to render trusted components from the catalog, reducing the risk of security vulnerabilities such as UI injection.
• LLM friendly: The flat, streaming JSON structure is designed to facilitate LLM generation. LLM can build the UI step-by-step without the need to generate perfect JSON at once, reducing the difficulty of generation.
• Dynamic update capability: A2UI supports dynamic updating of the interface, which can adjust the interface content in real time according to user operation or data changes, and enhance the flexibility of interaction.
• Open Source and Community Collaboration: A2UI is an open source project that encourages community participation, where developers can contribute code, suggest improvements, and work together to advance the project.

A2UI's core strengths

• safe and reliable: Adopting non-executable code design, all UI descriptions are static data, which avoids the security risk brought by code execution and ensures the security of the interface generation process.
• Efficient generation: The flat, streaming JSON structure is designed for easy LLM generation and supports AI agents to build UI step by step, which reduces the difficulty and improves the generation efficiency.
• cross-platform compatibility: The same JSON configuration can be rendered on multiple platforms such as Web, mobile, etc. It supports mainstream front-end frameworks such as Flutter, Angular, Lit, etc. and realizes a consistent user experience on multiple platforms.
• dynamic interaction: Support progressive rendering and dynamic update, able to adjust the interface content in real time according to user operations or data changes, enhancing the flexibility and smoothness of interaction.
• Easy to expand: The client application maintains a trusted component catalog, and the agent can only request components in the rendering catalog, reducing the risk of security vulnerabilities such as UI injection, while facilitating extension and maintenance.
• Community SupportAs an open source project, A2UI encourages community participation, where developers can contribute code, suggest improvements, and work together to promote the project's development and adapt to more application scenarios.

What is the official website of A2UI

• Project website:: https://a2ui.org/
• GitHub repository:: https://github.com/google/a2ui

Who A2UI is for

• AI developer: Developers working on AI agents or intelligent assistants, A2UI can help them quickly build dynamic user interfaces that enhance the experience of AI-user interaction.
• front-end engineer: Developers using front-end frameworks such as Flutter, Angular, Lit, etc. can easily realize cross-platform UI rendering with A2UI to improve development efficiency.
• product manager: Product managers who are concerned about user experience and interaction design, A2UI can help them quickly validate and iterate the product interface and optimize the user interaction process.
• data scientist: Scientists who need to dynamically present AI-generated data to users, A2UI supports dynamic updates and progressive rendering to better present data-driven interfaces.
• Corporate Technical Team: Teams looking to integrate AI capabilities into enterprise applications, A2UI provides a secure and efficient way to build AI-driven user interfaces for a wide range of business scenarios.