Add a2ui-oat: framework-free web renderer (v0.9)

[MisterTK]

Add a2ui-oat to Community Renderers

a2ui-oat is a lightweight, framework-free A2UI renderer for the web, built on Oat CSS semantic styling.

What it provides

• 37 catalog components — all 16 basic catalog components plus 21 Oat-native extensions (tables, pagination, progress, meter, skeleton loaders, toasts, tooltips, alerts, breadcrumbs, sidebars, accordions, switches, badges, avatars, video, audio, grid, dropdown, autocomplete, OatHTML escape hatch)
• 22 registered client-side functions — data (fetchPage, fetchAndAppend, subscribeSSE, subscribeWebSocket), navigation (openUrl, navigateTo), UI (showToast, debounce), formatting (formatDate, formatNumber, formatString, formatCurrency, pluralize), logic (and, or, not), validation (required, regex, length, numeric, email)
• ~13KB total client footprint — Oat CSS + JS + companion libraries, minified and gzipped
• Zero framework dependencies — no React, Angular, Lit, or build tooling required
• Custom catalog with theme support (7 properties mapped to CSS custom properties)
• @a2ui/web-lib integration via registerWithWebLib() one-call setup
• Dual-mode architecture — A2UI Mode (structured, catalog-validated) and Direct Mode (trusted agents emit semantic HTML)

Why this fills a gap

Every existing web renderer in the registry targets a framework (React, Lit, Angular). a2ui-oat is the first framework-free option — deploy via CDN include or npm install, no build step required. This makes it the lowest-friction path for agents that need to render A2UI on the web.

Links

• GitHub: https://github.com/MisterTK/a2ui-oat
• npm: https://www.npmjs.com/package/a2ui-oat
• Live demo: https://mistertk.github.io/a2ui-oat/
• Architecture doc: https://github.com/MisterTK/a2ui-oat/blob/main/docs/architecture.md
• Catalog validation: npm install a2ui-oat && npm run validate (16/16 checks pass)

Spec version

v0.9 only. Uses createSurface, updateComponents, updateDataModel message format with custom catalog support.

License

MIT

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[gemini-code-assist]

Code Review

This pull request adds the a2ui-oat renderer to the ecosystem documentation, updating the community renderer table and providing a detailed description of its features. Feedback was provided to shorten the description of a2ui-oat to maintain consistency with other entries in the document.

[gemini-code-assist]

This highlight description is quite detailed compared to the others in this section. To maintain consistency across the document and improve scannability, please consider shortening it to be a similar length to the other entries (2-3 sentences).

Here is a suggested revision that captures the key features more concisely:

Suggested change

**a2ui-oat** is the first framework-free web renderer, built on [Oat CSS](https://oat.ink/) semantic styling. It maps 37 catalog components (all 16 basic + 21 extensions) to semantic HTML with zero framework dependencies (~13KB total client footprint). It includes 22 registered client-side functions (pagination, SSE streaming, WebSocket, routing, formatting, validation), a custom catalog with theme support, and a dual-mode architecture that also supports direct HTML rendering for trusted agents. v0.9 only, with `@a2ui/web-lib` integration via `registerWithWebLib()`.

**a2ui-oat** is the first framework-free web renderer, built on [Oat CSS](https://oat.ink/) semantic styling. It provides 37 components and 22 client-side functions with a minimal footprint (~13KB). Key features include a custom catalog with theme support, a dual-mode architecture, and `@a2ui/web-lib` integration. v0.9 only.