Author your own Reyn web UI¶
Goal: swap Reyn's web UI for your own visual style without touching
Reyn's engine. The fastest path is claude.ai/design; this page gives
you a paste-ready prompt with a copy button.
How it works in one diagram¶
[your design] ⇄ [OpenUI Layer 0 protocol] ⇄ [Reyn engine]
↑ (window.OPENUI_HOST) ↑
you author (locked) never touch
Reyn's web shell wires the engine in at runtime. Your design only needs to follow the OpenUI protocol — no Reyn-specific glue code.
1. Copy the prompt¶
Click the copy icon at the top-right of the block, then paste it
into a fresh claude.ai/design thread.
# Reyn Design Prompt
You are designing a UI for **Reyn**, a workflow-engine-driven agent OS.
The design will integrate with Reyn via the **OpenUI Layer 0 protocol**
and the **reyn-ui/v1 Layer 1 schema**.
<!-- =================================================================
🔓 EDITABLE — fill in your design brief below.
Edit freely. This is your design intent.
================================================================= -->
## Your design brief
**Brand voice** (1–2 sentences):
> [REPLACE: e.g. "Warm and approachable but technically credible.
> Inspired by Linear's clarity and Stripe's precision."]
**Primary color**: [REPLACE: coral / amber / teal / monochrome / your-pick]
**Mode**: [REPLACE: light / dark / both]
**Density**: [REPLACE: cozy / comfortable / dense]
**Typography**:
- Body: [REPLACE: e.g. Inter, Geist, Söhne]
- Display (optional): [REPLACE: e.g. Instrument Serif for App headers only]
- Mono (Studio only): [REPLACE: e.g. JetBrains Mono, IBM Plex Mono]
**Screens to prioritise** (App side):
- [REPLACE: Today, Conversation, Agent gallery, Library card → guided run]
**Screens to prioritise** (Studio side):
- [REPLACE: Conversation+inspector, Skill graph, Run timeline, Permissions]
**Inspirations** (optional): [REPLACE]
**Avoid** (optional): [REPLACE]
<!-- =================================================================
🔒 LOCKED — DO NOT EDIT BELOW THIS LINE.
This is the OpenUI / reyn-ui/v1 protocol contract. Editing it
will break the engine ↔ design integration.
================================================================= -->
## What is Reyn
Reyn lets non-technical users converse with specialist AI agents and
lets developers build & ship those agents from Markdown. The Reyn UI
has **two faces**:
- **App** — friendly end-user surface (default landing). Tone:
Claude.ai / OpenClaw / ChatGPT. Hides engine vocabulary entirely.
- **Studio** — dense developer surface. Build & debug skills, inspect
runs, edit permissions. Tone: Linear / Vercel / Cursor / Temporal /
LangSmith. Surfaces engine vocabulary verbatim.
The two faces share agent identity (name, color, avatar) and a
top-right App ↔ Studio toggle, but **share nothing else** — different
chrome, density, vocabulary.
## How the design connects to the engine
Reyn implements the **OpenUI Layer 0 protocol**. The design reads four
globals on `window`:
- `window.OPENUI_HOST` — `{ invoke(action, payload?), listen(channel, handler) }`
- `window.OPENUI_DATA` — initial data (shape: `ReynUiData`)
- `window.OPENUI_SCHEMA` — `"reyn-ui/v1"`
- `window.OPENUI_DESIGN_MODE` — `true` standalone, `false` embedded
## Required components, data shape, actions, channels
Specified canonically in:
- Component contracts: `docs/deep-dives/spec/openui/schemas/reyn-ui-v1/components.md`
- Data shape (`ReynUiData`): `docs/deep-dives/spec/openui/schemas/reyn-ui-v1/data.types.ts`
- Actions / channels: `docs/deep-dives/spec/openui/schemas/reyn-ui-v1/manifest.yaml`
Treat as the contract: every required component must be exported,
prop shapes must match, action / channel names must be used as defined.
## Hard rules
- **No hardcoded mock data inside components.** Read from
`window.OPENUI_DATA` when embedded, fallback mock when standalone.
Mock lives in a separate `data.js`.
- **All user actions go through `window.OPENUI_HOST.invoke()`.** Every
user-driven side-effect (sending a message, answering an
intervention, attaching to an agent, switching face, accepting a
permission, cancelling a run) MUST `await
window.OPENUI_HOST.invoke(<action>, <payload>)`. Local-only state
updates stay in component state.
- **All async data goes through `window.OPENUI_HOST.listen()`** with
unsubscribe on unmount.
- **No `fetch` / `XMLHttpRequest` / `WebSocket` calls in components.**
- **No global state libraries** (Zustand, Redux, …). Local state only.
- **No bundler / framework configs.** The host owns the build.
- **App face vocabulary**: never expose `phase`, `artifact`,
`control_ir`, `event`, `validation`, `schema`. Studio uses these
verbatim.
- **i18n**: App face strings come from `OPENUI_DATA.COPY[lang]`.
- **Two HTML entries (REQUIRED)**:
- `Reyn.html` — host-mountable runtime, hash-routed App/Studio
mount, no artboards. This is what `reyn web` loads.
- `Reyn UI.html` — design canvas with artboards (designer mode only).
- **`Reyn.html` MUST trigger Babel transformation explicitly** if it
uses babel-standalone:
```html
<script>
(function () {
var t = setInterval(function () {
if (window.Babel && Babel.transformScriptTags) {
clearInterval(t);
Babel.transformScriptTags();
}
}, 50);
})();
</script>
```
Auto-runner fires on DCL, which has already passed when the host
shell injects the design.
## Now generate
Append one of these on the next line and send:
> `→ App + Studio` (recommended — both faces in one export)
>
> `→ App` (App face only)
>
> `→ Studio` (Studio face only)
Begin by enumerating which screens you'll cover and your token /
typography proposal, then iterate.
2. Fill in the brief¶
Inside claude.ai/design, edit ONLY the section between the
🔓 EDITABLE markers. Replace each [REPLACE: …] placeholder with
your choice. Leave everything below 🔒 LOCKED untouched.
3. Iterate visually¶
Tweak colors, layout, copy in plain English on the canvas chat. Don't ask Claude Design to change the OpenUI globals or component names — those are the locked contract that lets Reyn's engine wire in.
4. Export and drop in¶
Use Export → .zip, then:
DESIGN=warm-coral # whatever slug you like
mkdir -p "reyn/local/designs/$DESIGN"
unzip ~/Downloads/Reyn-export.zip -d "reyn/local/designs/$DESIGN"
Refresh / restart reyn web. The design picker discovers it
automatically.
Example briefs¶
Default coral¶
Brand voice: Warm and approachable, like a knowledgeable friend.
Inspired by Claude.ai App tone and Stripe's precision.
Primary color: coral
Mode: light
Density: comfortable
Body: Inter
Display: Instrument Serif (App headers only)
Mono: JetBrains Mono (Studio)
Inspirations: Claude.ai, Linear, OpenClaw
Avoid: generic SaaS purple, Tailwind-default look
Dark monochrome (terminal-inspired)¶
Brand voice: Quiet competence. The interface gets out of the way.
Inspired by Vercel and the bare elegance of well-tuned
terminal apps.
Primary color: monochrome (zinc 50→950)
Mode: dark
Density: dense
Body: Inter
Mono: JetBrains Mono
Inspirations: Vercel dashboard, Linear's dark mode, Warp
Avoid: any color that isn't a neutral
Nordic¶
Brand voice: Cool, precise, breathing. Inspired by Nordic minimal
design and the Notion-but-quieter aesthetic.
Primary color: muted blue-gray (oklch 0.62 0.06 240)
Mode: both
Density: cozy
Body: Inter
Display: Söhne (App)
Mono: IBM Plex Mono
Inspirations: Notion, Things 3, Bear Notes
Avoid: anything saturated
Troubleshooting¶
- White screen — host shell can't see the design's globals. Most
often: the
Babel.transformScriptTags()polling snippet is missing. - Design doesn't appear in the picker — check
reyn/local/designs/<slug>/Reyn.htmlexists. The shell fetches exactly this filename. - Engine doesn't respond to messages — your
submithandler isn't callingwindow.OPENUI_HOST.invoke('agent.submit', { agentId, text }). The PR31-era v1 export had this bug; check the design'sapp-screens.jsxandstudio-screens.jsxfor the wiring. - Styles don't apply — the design's
<link href="styles.css">tag must be inside the design's HTML, not in the shell. The shell rewrites the relative URL automatically.
See also¶
The full operational guide and the OpenUI Layer 0 protocol spec live in
the repository under docs/deep-dives/spec/design/ and
docs/deep-dives/spec/openui/ (= internal contract docs, not part of
the public site). Browse them on GitHub if you need the deeper detail:
docs/deep-dives/spec/design/design-author-guide.md— the full operational guide (richer than this how-to)docs/deep-dives/spec/design/multi-design-selection.md— three-root layout (local/project/ bundled), selection prioritydocs/deep-dives/spec/openui/— the OpenUI Layer 0 protocol spec (you don't need to read it to author a design; it's the contract the locked zone enforces)