A2UI (Agent to UI) Protocol

This repository contains the specification for the A2UI protocol, a JSONL-based, streaming UI protocol designed to be easily generated by Large Language Models (LLMs).

Project Overview

The A2UI protocol enables a server to stream a platform-agnostic, abstract UI definition to a client, which then renders it progressively using a native widget set. The core design principles are:

• LLM-Friendly: The protocol uses a simple, declarative, and flat structure that is easy for LLMs to generate.
• Progressive Rendering: The UI is streamed as a series of JSONL messages, allowing the client to render the UI as it arrives, improving perceived performance.
• Platform-Agnostic: The protocol defines an abstract component tree, and the client is responsible for mapping these abstract components to its native widget implementations.
• Separation of Concerns: The protocol separates the UI structure (components), the application state (data model), and the client-side widget rendering.

Repository Layout

The repository is structured as follows:

• docs/: This directory contains general information about the A2UI protocol .
• specification/: Contains formal specification documents and JSON schemas for the protocol.