The Map: A2UI isn’t a lonely island. It lives in a bustling city of AI tools. Here is how the pieces fit together.
The 3-Layer “Agentic Stack”
Building a modern AI Product requires multiple, decoupled layers. As the industry standardizes, A2UI handles the Native-First Presentation Layer.
| Layer | Responsibility | Players |
|---|---|---|
| Intelligence | The Brain | GPT-4o, Gemini 2.5, Claude 3.5 |
| Orchestration | The Brain’s Logic & Workflows | LangChain, Oracle Open Agent Spec |
| Interaction | The Event Stream & Tool Calls | AG-UI (CopilotKit), Vercel AI SDK |
| Context (Data) | The Extensible Memory | MCP (Model Context Protocol) |
| Presentation | The Visual Face & Surfaces | A2UI, MCP Apps (Iframes), React, Flutter |
Ecosystem Players
1. CopilotKit (The Integrator)
CopilotKit is the Rocket Ship. A2UI is the Engine.
CopilotKit provides the plug-and-play SDKs (<CopilotSidebar />) that internally use A2UI to render the UI.
- Learn about CopilotKit
- Official Tool: Use the official A2UI Composer to generate and inspect declarative interfaces.
2. Flutter GenUI SDK (Official Validation)
As explicitly featured in the official specifications, the GenUI SDK serves as a primary reference implementation for A2UI on mobile and desktop clients. It leverages A2UI under the hood to stream native Dart/Flutter widgets generated by intelligent agent workflows.
2. Model Context Protocol (The Context & Tools)
MCP, now governed by the Agentic AI Foundation, allows Agents to read your calendar, files, and database seamlessly (surpassing 97M monthly SDK downloads as of early 2026). While the recent MCP Apps extension allows rendering full HTML iframes as UI resources, A2UI complements this by focusing strictly on Native Presentation.
- MCP = Input (Context & Tools) and isolated HTML Sandboxes
- A2UI = Output (Native Component Blueprints)
3. Enterprise Mesh (A2A)
In large companies, “Sales Agent” talks to “Legal Agent”. They need a standard language. A2UI is that language.
- Scenario: Sales Agent asks Legal Agent for a contract draft. Legal Agent replies with a
contract-viewerUI component, which the Sales Agent forwards to the user.
Why Open Standard Matters?
Proprietary standards lock you in.
- OpenAI Actions: Locked to ChatGPT.
- A2UI: Open Source. You own the renderer. You own the components. You own the user experience.