What's the prompt for the Particleforge test?

Particle Forge — sculpt swirling particle systems with mouse gravity. Every model receives this exact prompt, one shot, single HTML file out.

Sim

Particleforge

Q: What's the best AI model for Particleforge?

Claude Opus 5 — Gorgeous dense 26k-particle field with rich additive-blended color, glow sprites, and a comprehensive control panel (7 shapes, 4 gravity modes, force/pull sliders, burst/pause/auto-orbit) plus live stats at 69 FPS. Only minor nit: the current shape reads more like a diffuse cloud than a crisp torus, but overall this clearly matches/tops the field's best.

Q: How many AI models attempted Particleforge?

24 models on Goldie Bench have attempted Particleforge: Claude Fable 5, Fugu Ultra, Fugu Mini, Fusion, Gemini 3.6 Flash, GLM-5.2, GPT-5.6 Sol, Grok, Inkling, Kimi K2.7, Kimi K3, MiniMax M3, Hermes MoA, Muse Spark 1.2, Opus 4.8, Claude Opus 5, Qwen 3.8, Qwen 3.7, Claude Sonnet 5, Kimi K2.7 · Fast, Kimi K2.7 · No-Think, Kimi K2.7 · Quality, DeepSeek V4 Pro, DeepSeek V4 Flash.

Particle Forge — sculpt swirling particle systems with mouse gravity.

CategorySim

Models tested24

Scored19/24

Avg score7.39/10

WinnerClaude Opus 5

What I asked each model — the Particleforge prompt

Every model on this page got this exact prompt inside the Agent Operating System: Particle Forge — sculpt swirling particle systems with mouse gravity.

Single HTML file out. No iteration. No examples in the system prompt. Whatever each model produced on the first run is what's on this page. 24 frontier models have attempted it so far: Claude Fable 5, Fugu Ultra, Fugu Mini, Fusion, Gemini 3.6 Flash, GLM-5.2, GPT-5.6 Sol, Grok, Inkling, Kimi K2.7, Kimi K3, MiniMax M3, Hermes MoA, Muse Spark 1.2, Opus 4.8, Claude Opus 5, Qwen 3.8, Qwen 3.7, Claude Sonnet 5, Kimi K2.7 · Fast, Kimi K2.7 · No-Think, Kimi K2.7 · Quality, DeepSeek V4 Pro, DeepSeek V4 Flash.

Why this task matters. Particleforge is a textbook test of sim-class capability — the kind of build that exposes whether a model is doing pattern-matching or actual reasoning. Shipping this cleanly is the floor for what I expect from a frontier model — every model on the leaderboard should at least attempt it.

How each model handled Particleforge

Ranked by my 0–10 score from the source comparison guides on agentos.guide. Click any to play the actual one-shot HTML the model produced.

Claude Fable 5 Anthropic

• 7.6/10

What I saw: Clean render with a glowing forge core, ringed particle formation and legible mode/hint HUD; the repel state correctly pushes particles into a crisp orbital shell. However the particles read mostly white with muted hue variation and the arrangement is a static ring rather than dynamic swirling, keeping it strong-but-shy of the field's best.

▶ Play Claude Fable 5's attempt →

Fugu Ultra Sakana AI

• 8.0/10

What I saw: Ultra v2 (gap-fill) — mouse-gravity particle sculptor. Smoke-test PASS (2.6% diff).

▶ Play Fugu Ultra's attempt →

Fugu Mini Sakana AI

• 8.0/10

What I saw: Mouse-gravity particle sculptor. Smoke-test PASS (8.4% pixel diff).

▶ Play Fugu Mini's attempt →

Fusion OpenRouter

🥈 8.5/10

What I saw: Particle Forge — sculpt swirling particle systems with mouse gravity. Multiple presets (vortex/attractor/repulsor/magnet), colour schemes, FPS counter. 19KB.

▶ Play Fusion's attempt →

Gemini 3.6 Flash Google

• 3.5/10

What I saw: Polished glassmorphism UI with presets and sliders, but the core requirement—visible swirling particles—is completely absent in the screenshot, showing only an empty gradient background. The WebGL particle system failed to render, gutting the entire brief.

▶ Play Gemini 3.6 Flash's attempt →

GLM-5.2 Zhipu / Z.ai

• 7.5/10

What I saw: 32KB · plays clean · plain

▶ Play GLM-5.2's attempt →

GPT-5.6 Sol OpenAI

🥉 8.4/10 · polished 3D forge

What I saw: Strong: a beautifully rendered 3D particle ring with glowing core, orbital rings, and gradient particle coloring, backed by a clean glassy control panel with attract/repel modes, force slider, and burst — polished and clearly on-brief. Slight weakness is the particles reading as a static torus shell in the still rather than a chaotic swirling well, but the interaction hooks and Three.js physics are all present.

▶ Play GPT-5.6 Sol's attempt →

Grok xAI

• 8.0/10

What I saw: Sculpt swirling particle systems with mouse gravity, multiple presets, FPS counter. 18KB.

▶ Play Grok's attempt →

Inkling Thinking Machines

• 3.2/10

What I saw: The title typography is gorgeous with a clean gradient and neon glow, but the actual particle system barely renders — only a handful of scattered dots and one clustered blob are visible instead of 8000 swirling particles, so the core brief (sculpting a particle swirl) is effectively broken/invisible.

▶ Play Inkling's attempt →

Kimi K2.7 Moonshot AI

• 7.5/10

What I saw: Particle sculptor with mouse gravity + preset modes.

▶ Play Kimi K2.7's attempt →

The winner on Particleforge

Claude Opus 5 took gold on this task. Colorful particle forge.

What I saw: Gorgeous dense 26k-particle field with rich additive-blended color, glow sprites, and a comprehensive control panel (7 shapes, 4 gravity modes, force/pull sliders, burst/pause/auto-orbit) plus live stats at 69 FPS. Only minor nit: the current shape reads more like a diffuse cloud than a crisp torus, but overall this clearly matches/tops the field's best.

See Claude Opus 5's full model card: /models/opus5. Direct head-to-head against the runner-up: Claude Opus 5 vs Fusion.

Every attempt — live, playable

Side by side. Click any tile to run that model's actual one-shot HTML in a new tab.

▶ LIVE

Claude Fable 5

Anthropic

Clean render with a glowing forge core, ringed particle formation and legible mode/hint HUD; the repel state correctly pushes particles into a crisp orbital shell. However the particles read mostly white with muted hue variation and the arrangement is a static ring rather than dynamic swirling, keeping it strong-but-shy of the field's best.

▶ LIVE

Fugu Ultra

Sakana AI

Ultra v2 (gap-fill) — mouse-gravity particle sculptor. Smoke-test PASS (2.6% diff).

▶ LIVE

Fugu Mini

Sakana AI

Mouse-gravity particle sculptor. Smoke-test PASS (8.4% pixel diff).

▶ LIVE

Fusion 🥈

OpenRouter

Particle Forge — sculpt swirling particle systems with mouse gravity. Multiple presets (vortex/attractor/repulsor/magnet), colour schemes, FPS counter. 19KB.

▶ LIVE

Gemini 3.6 Flash

Google

Polished glassmorphism UI with presets and sliders, but the core requirement—visible swirling particles—is completely absent in the screenshot, showing only an empty gradient background. The WebGL particle system failed to render, gutting the entire brief.

▶ LIVE

GLM-5.2

Zhipu / Z.ai

32KB · plays clean · plain

▶ LIVE

GPT-5.6 Sol 🥉

OpenAI

Strong: a beautifully rendered 3D particle ring with glowing core, orbital rings, and gradient particle coloring, backed by a clean glassy control panel with attract/repel modes, force slider, and burst — polished and clearly on-brief. Slight weakness is the particles reading as a static torus shell in the still rather than a chaotic swirling well, but the interaction hooks and Three.js physics are all present.

▶ LIVE

Grok

xAI

Sculpt swirling particle systems with mouse gravity, multiple presets, FPS counter. 18KB.

▶ LIVE

Inkling

Thinking Machines

The title typography is gorgeous with a clean gradient and neon glow, but the actual particle system barely renders — only a handful of scattered dots and one clustered blob are visible instead of 8000 swirling particles, so the core brief (sculpting a particle swirl) is effectively broken/invisible.

▶ LIVE

Kimi K2.7

Moonshot AI

Particle sculptor with mouse gravity + preset modes.

▶ LIVE

Kimi K3

Moonshot AI

Polished chrome — gradient title, presets, gravity slider, glowing core and 61fps at 14k particles all read well, and the trails/orbiter system is real. But the screenshot shows only a sparse thin ring of orbiters rather than a dense swirling forge of particles, so the core 'sculpt swirling systems' visual feels underwhelming and empty compared to the field's best.

▶ LIVE

MiniMax M3

MiniMax

Particle sculptor with mouse gravity + preset modes + FPS counter.

▶ LIVE

Hermes MoA

Hermes · Mixture of Agents

Polished particle sculptor with smooth gravity/swirl physics, mode toggle, bursts, idle drift, and a nice glowing aesthetic with reticle — clearly beats SOLO Opus 4.8's plain build and edges past Grok/Fugu, but it lacks the multiple preset modes (vortex/attractor/repulsor/magnet) and FPS counter that give Fusion (8.5) its breadth, so it lands just shy of the field leader.

▶ LIVE

Muse Spark 1.2 🥉

How I scored Particleforge — methodology

Three axes, 0–10 each, averaged. Runs: drop the .html in a browser; if it opens to a broken page, it scores zero. Hits the brief: did the model ship the thing the prompt asked for, or a different thing it found easier. Looks good: visual polish, motion, interactivity — where most of the gap between gold and silver lives.

My scores trace back to the source comparison guides on agentos.guide. See the full methodology page for data provenance, including which source guide each cell's score came from.

More sim benchmarks: all tasks in the Sim category · See the best AI model for Particleforge · Back to the leaderboard

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Particleforge

What I asked each model — the Particleforge prompt

How each model handled Particleforge

The winner on Particleforge

Every attempt — live, playable

How I scored Particleforge — methodology

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