feat(renderers): Add React Native renderer

[sivamrudram-eng]

Summary

This PR adds the first React Native implementation of the A2UI renderer, enabling A2UI-compliant agents to generate native mobile UIs on iOS and Android.

Features

Core Components

• A2UIRenderer - Main component for rendering A2UI specifications
• useA2UIStream - Hook for real-time streaming from agent servers

MVP Components (8 of 16)

Component	React Native Mapping	Status
Text	<Text>	✅
Button	<Pressable>	✅
Image	<Image>	✅
Row	<View flexDirection="row">	✅
Column	<View>	✅
Card	<View> with shadow	✅
List	<FlatList>	✅
TextField	<TextInput>	✅

Infrastructure

• JSONL stream parser for real-time updates
• Message dispatcher for A2UI protocol messages
• Surface registry and component buffer for state management
• Data binding support with BoundValue resolution
• Full TypeScript support

Usage Example

import { A2UIRenderer } from "@a2ui/react-native";

const App = () => {
  const spec = {
    surfaceId: "main",
    rootId: "root",
    components: [
      { id: "root", type: "Column", children: ["text1", "btn1"] },
      { id: "text1", type: "Text", content: "Hello A2UI!" },
      { id: "btn1", type: "Button", label: "Click me", action: "doSomething" },
    ],
  };

  return <A2UIRenderer spec={spec} onAction={handleAction} />;
};

Roadmap

• Add remaining components (Modal, Tabs, Slider, etc.)
• Add comprehensive test suite
• Publish to npm as @a2ui/react-native

Implements #428

Standalone Repository

This renderer is also available as a standalone package at:
https://github.com/sivamrudram-eng/a2ui-react-native

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[zeroasterisk]

Nice work @sivamrudram-eng

@ataibarkai is leading the effort for an A2UI react renderer.

Atai and CopilotKit team, can you please review this PR and see what you might want for the official implementation?

Regardless of the outcome (because I think Atai and team are kind of far into their work) we would welcome your future contributions and refinements to make the A2UI react renderer better. We also have a v0.9 spec ~done and there will be improvements to each of these renderers to support v0.9, possibly backwards compatibility, certainly better decoupling of transport and shared library functions... lots more stuff to do :)

[zeroasterisk]

Thanks for this substantial contribution @sivamrudram-eng — 21k lines with 44 files is serious work!

A few notes on where this fits:

1. React Native vs React (web): These are separate efforts. @lukasmoschitz and CopilotKit are leading the React web renderer (Add React renderer #542), but React Native targets a different runtime (native iOS/Android vs browser DOM). There could be opportunities to share protocol/state management logic, but the component implementations are necessarily different.

2. Repo restructuring: We're considering restructuring soon — renderers may move to their own repos within an org. This would give each renderer (Lit, Angular, React, React Native, Flutter) more autonomy and clearer ownership.

3. v0.9 spec: We're close to landing v0.9, which includes better shared library separation and transport decoupling. Any renderer merged now will need updates for v0.9 compatibility.

⚠️ Ownership expectations

Owning a renderer is a significant ongoing commitment — keeping up with spec changes, handling issues, reviewing community PRs, etc. The core team's bandwidth is limited, and we likely won't be able to provide regular reviews or maintenance support for React Native.

Given that, it might be easier to start this as a standalone repo (your own or under an A2UI community org) rather than merging into the monorepo. That way you have full autonomy and aren't blocked waiting on us.

If you're interested in that path, we're happy to link to it from the official docs as a community renderer. Let us know what you think!

Appreciate you pushing the A2UI ecosystem forward! 🙌