claude ai design prototyping anthropic design tools

I gave Fable 5 my hardest design prompts. Here's what came back.

Anthropic's new flagship model just mass-obsoleted a decade of prototyping tools. Three prompts, three single-file apps, zero compromises.

MN

Mark Nguyen

Anthropic just shipped Fable 5 — their new flagship — and I needed to know, can it design? Afterall, this is The Design Engineer, afterall.

So I created 4 frontend apps to push the model to its limits. What came back, genuinely blew me away.

1. ORRERY

Here’s the first prompt I threw at Fable 5. A fully procedural, WebGL solar system portfolio — one self-contained HTML file, no build step, no external assets.

The prompt

Prompt #1 — Orrery
You are a creative technologist at a studio famous for award-winning WebGL sites. Build ORRERY: a portfolio site where the navigation IS a stylized solar system, in ONE self-contained HTML file (Three.js r160+ via CDN import map, custom GLSL, no build step, no external assets — every texture must be procedural).

THE SCENE
- A central sun built from layered fractal brownian motion (fBm) noise in a fragment shader: animated surface convection, rim-darkened limb, and a corona rendered as a separate additive-blended billboard shader. The sun is the page's light source — all planets receive its light direction in their shaders.
- 5 planets, each representing a portfolio project, each with a DISTINCT procedural material:
  1. Molten world — flowing lava using domain-warped noise, emissive cracks
  2. Ocean world — animated normal-mapped waves + Fresnel atmosphere rim
  3. Gas giant — banded turbulence (curl noise) with a slowly rotating storm vortex
  4. Ice world — sharp voronoi cellular cracks with subsurface-scatter fake glow
  5. Terra world — continents from thresholded fBm, day/night terminator with city lights on the dark side
- Planets orbit on inclined elliptical paths at different speeds. Thin glowing orbit lines. A sparse starfield + faint procedural nebula background (big inverted sphere, fBm in fragment shader).

CINEMATOGRAPHY & INTERACTION
- Scroll does NOT scroll a page — it drives the camera along a choreographed spline that gravity-slingshots from planet to planet. Use damped scroll (lerp toward target) so motion feels weighty.
- As the camera approaches each planet, a project card (HTML overlay, glassmorphic, kinetic type) slides in, synced to camera distance. Typography: a characterful display face from Google Fonts + a clean grotesque for body. Pick something NOT Inter/Space Grotesk defaults.
- Clicking a planet triggers a dive: camera accelerates into the atmosphere, screen fills with that planet's shader colors via a custom full-screen transition shader (radial distortion + chromatic aberration), then cross-dissolves to a full case-study panel. Escape reverses it.
- Cursor exerts a tiny gravitational pull on nearby planets (springs back). Subtle, not gimmicky.

POLISH BAR
- Post-processing: bloom (selective on sun/emissives), filmic tonemapping, vignette, gentle film grain.
- 60fps target on a mid laptop: cap pixel ratio at 1.5, no shadow maps, share geometries.
- Loading sequence: planets scale in with staggered elastic easing while the sun ignites (uniform ramp).
- Respect prefers-reduced-motion (static layout fallback with planets as a vertical list). Keyboard nav between planets with visible focus.
- Invent real-sounding project copy (names, one-line descriptions, 3 stats each). No lorem ipsum.

Before coding, write a 10-line design plan (palette as named hexes, type pairing, the one signature moment). Then build the complete file. Self-critique against the plan before finalizing.

2. Teenage Engineering-inspired music sequencer

Next, I wanted to see if Fable 5 could handle a more complex UI. I asked it to create a music sequencer inspired by Teenage Engineering’s OP-1, complete with a grid-based step sequencer, a virtual keyboard, and a simple mixer.

The prompt

Prompt #2 — Teenage Engineering
Build an interface inspired by teenage engineering. the objective is to showcase your (Fable 5) design capabilities.

3. “Attention Is All You Need” — explained in 60 seconds

Finally, the big one. I wanted to see if Fable 5 could turn a dense research paper into something cinematic. This is a single-file, auto-advancing explainer of the Transformer’s attention mechanism — complete with live softmax math, eight attention heads, and a full architecture diagram. Press play and sit back.

The prompt

Prompt #3 — Attention Is All You Need
Build a single-file interactive web experience that explains the Transformer 
("Attention Is All You Need", Vaswani et al., 2017) in exactly 60 seconds. 
Think of it as a playable movie: an auto-advancing, cinematic journey with 
perfect pacing — Apple keynote meets Distill.pub. The user presses one 
button and is taken through the core idea with zero effort, but can pause 
and scrub at any moment.

THE 60-SECOND TIMELINE (auto-advancing scenes):

  0:00–0:08 — THE HOOK
  Black screen. The sentence "The animal didn't cross the street because 
  it was too tired" fades in, one word at a time. The word "it" pulses. 
  Text: "What does 'it' refer to? You know instantly. Here's how a machine 
  learned to."

  0:08–0:20 — ATTENTION REVEALED
  Animated attention lines bloom from "it" to every other word, thickness 
  proportional to real computed attention weights. The line to "animal" 
  glows brightest. Text: "Every word looks at every other word and decides 
  what matters. This is attention."

  0:20–0:32 — THE MATH, FAST
  The sentence morphs into small Q, K, V matrices. A rapid but legible 
  animated pipeline: Q·Kᵀ → ÷√d_k → softmax → ×V, each step landing with 
  a satisfying snap and a 3-word label. Real numbers, computed live in JS.

  0:32–0:44 — MANY HEADS, MANY MEANINGS
  The view splits into 8 panels — 8 attention heads on the same sentence, 
  each lighting up different word relationships simultaneously. Text: 
  "8 heads, each learning a different kind of relationship — in parallel."

  0:44–0:54 — THE FULL MACHINE
  Camera zooms out: the attention block we just watched shrinks and slots 
  into the full encoder-decoder architecture diagram. Data pulses flow 
  through all layers. Text: "Stack it 6 times. No recurrence. No 
  convolution. Attention is all you need."

  0:54–1:00 — THE PAYOFF
  Architecture fades to a single line: "This idea powers GPT, Claude, and 
  modern AI." A replay button and an "Explore freely" button appear.

INTERACTION MODEL:
- Starts with a single elegant "Play" button on a title card
- A thin timeline scrubber at the bottom: pause, scrub, jump to any scene
- Spacebar pauses; while paused, the current scene becomes interactive 
  (e.g. in scene 2, click any word to see ITS attention lines)
- "Explore freely" at the end unlocks a free-play attention playground

DESIGN REQUIREMENTS:
- Cinematic dark theme: near-black background, cyan→magenta gradient for 
  attention weights, one display typeface for big statements
- Every transition choreographed — elements morph between scenes rather 
  than cut (the sentence becomes the matrices, the matrices become the 
  architecture block)
- 60fps animations via requestAnimationFrame; easing on everything
- Big, confident typography; never more than one sentence on screen

TECHNICAL CONSTRAINTS:
- Single self-contained HTML file, vanilla JS or D3 from CDN, no build step
- All attention weights computed live with real scaled dot-product math 
  on small demo vectors — nothing hardcoded as images
- A master timeline controller driving all scenes, so scrubbing is 
  frame-accurate

The bar: a viewer with no ML background should reach 1:00 and genuinely 
understand what attention is — and feel like they just watched something 
beautiful.

4. Monsterbound — a monster-catching RPG

Could Fable 5 build an entire game? Not a toy — a real RPG with a tile-based overworld, type-triangle combat, XP and levelling, wild encounters, and a catch mechanic. One prompt, one HTML file, fully playable. Choose a starter and walk into the tall grass.

The prompt

Prompt #4 — Monsterbound
Build a complete monster-catching RPG in the style of classic handheld
games, as a single self-contained HTML file (inline CSS and JS, no
frameworks, no localStorage — all state in memory). Use original
creatures only: no Pokémon names, characters, or assets.

GAME STRUCTURE — three screens:
1. Title screen: game name "Monsterbound" and a choice of 3 starters,
   each shown as a card with sprite, name, type badge, one-line flavor
   text, and a Choose button.
2. Overworld: a 16×12 tile map drawn on a <canvas> (32px tiles).
   Tile types: grass (walkable), tall grass (walkable, 18% chance per
   step of a wild encounter), trees and water (blocked), path, and a
   red-roofed house that fully heals the party when stepped on.
   Border the map with trees. Show the party as small cards above the
   canvas (sprite, name, level, HP bar) plus a toast line for messages.
   Move with on-screen d-pad buttons AND arrow keys/WASD.
3. Battle screen: enemy panel top (name, level, HP bar, sprite),
   player panel below (same, plus HP numbers and a thin XP bar),
   a one-line message log, and action buttons: Fight / Catch / Run.
   Fight opens a 2-column move menu showing each move's type and power,
   with a Back button.

CREATURES — 5 species with base stats (hp/atk/def/spd) and movepools:
- Embercub (fire): Scratch, Ember, Flame whirl
- Puddlit (water): Tackle, Bubble jet, Tide snap
- Leaflit (leaf): Tackle, Leaf dart, Vine lash
- Fluffowl (normal): Peck, Gust
- Buzzlebee (normal, fast/frail): Buzz, Gust
First three are the starters (level 5). Draw each as a small inline
SVG sprite — round body, eyes, smile, plus one signature feature
(flame tail, head fin, leaf sprout, owl wings, bee stripes).

BATTLE MECHANICS:
- Type triangle: fire > leaf > water > fire (2x), reversed = 0.5x,
  same-type vs same-type = 0.5x, normal is neutral. Show "It's super
  effective!" / "It's not very effective..." messages.
- Damage: classic formula shape — ((2·level/5 + 2) · power · atk/def)
  / 50 + 2, times type multiplier, times random 0.85–1.0, minimum 1.
- Stats scale with level (~12–16% of base per level). Turn order by
  speed. Enemy picks a random move. Resolve turns step by step with
  ~800ms delays between log messages; disable actions while resolving.
- Catch: chance = 0.25 + 0.6·(1 − currentHP/maxHP), with throw and
  wobble messages. Caught monsters join the party (max 6).
- Run: 70% success; on failure the enemy gets a free attack.
- XP: 22 × enemy level per win; level-up at level×40 XP, recompute
  stats keeping damage taken, learn the third move at level 7.
- If the active monster faints, send out the next healthy one; if none
  remain, return the player to the start tile with a healed party.
- Wild encounters: weighted species pool (Fluffowl most common,
  Buzzlebee rare), level = highest party level −2 to +1, minimum 2.

LOOK AND FEEL:
- Frame the whole game inside a chunky handheld console shell: deep
  pine-green plastic, dark bezel, pale mint LCD screen, working d-pad
  below the screen with a small control legend beside it.
- Pixel font (Press Start 2P with monospace fallback) for headings and
  buttons; monospace body text. Cards get 2px ink borders with offset
  block shadows for a retro sticker look. Coral-red accent buttons.
- HP bars shift green → amber → red. Brief screen flash on encounters.
- Visible keyboard focus styles; respect prefers-reduced-motion.

Conclusion

My takeaway is that designers yet again, have another very, very capable tool to add to their belts. There’s no hint whatsoever of AI slop, and some of the interaction design, like in the Teenage Engineering demo, is something that would likely have taken me several weeks of iterating to fine tune.

It is really an exciting time to be a designer.

Anthropic has kindly gifted us Fable 5 usage until June 22nd (my birthday! 🥳), after which it will be charged on usage basis.