Generative UI

Understanding AG-UI’s relationship with generative UI specifications

AG-UI and Generative UI Specs

Several recently released specs have enabled agents to return generative UI, increasing the power and flexibility of the Agent<->User conversation.

A2UI, MCP-UI, and Open-JSON-UI are all generative UI specifications. Generative UIs allow agents to respond to users not only with text but also with dynamic UI components.

Specification	Origin / Maintainer	Purpose
A2UI	Google	A declarative, LLM-friendly Generative UI spec. JSONL-based and streaming, designed for platform-agnostic rendering.
Open-JSON-UI	OpenAI	An open standardization of OpenAI’s internal declarative Generative UI schema.
MCP-UI	Microsoft + Shopify	A fully open, iframe-based Generative UI standard extending MCP for user-facing experiences.

Despite the naming similarities, AG-UI is not a generative UI specification — it’s a User Interaction protocol that provides the bi-directional runtime connection between the agent and the application.

AG-UI natively supports all of the above generative UI specs and allows developers to define their own custom generative UI standards as well.