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Ship Harness Bench

A benchmark to evaluate the quality of different LLM coding harnesses. Same model, same prompt, different tools.

19 agents · same prompt · different results
The Prompt
"Create a beautiful, relaxing, 3D ship simulator for the browser with the sun in the horizon alternating day and night and when you click on the sea the water makes a wave"
Model: Deepseek V4 Flash 0731
Models
GLM-5.3744B total · 40B active
MoE · ~753B checkpoint
MiMo v2.5310B total · 15B active
MoE
DeepSeek V4 Flash 0731284B total · 13B active
MoE · 304B with DSpark module
Qwen3.6-35B-A3B35B total · 3B active
MoE
Qwen3.8-27B27B total · dense
dense
Muse Spark 1.3undisclosed
proprietary, closed · size not published
Takeaways

Harness matters

The model is important, but the harness is a worthy optimization. Same model, vastly different results depending on the tooling.

Browser-use is key

A good browser-use tool is one of the most useful skills. Seeing, interacting with, and verifying output in a real browser is a game changer.

Memory helps

Memory and other tools could also be useful. Context retention and auxiliary capabilities shape output quality as much as the model itself.

The Agents
🌊
Codex

Ship Sim

Import maps, modular Three.js, day/night cycle with wave controls.

🌅
DSH

Open Sea

Self-contained single HTML with inline Three.js bundle. Keyboard sailing controls.

⛵
Jcode

Voyager

Clean vanilla JS with verification scripts. Minimal and focused approach.

✨
Jcode FX

Ship Simulator

Enhanced variant with bun-built bundle. Polished visual effects.

🌇
Jcode 2

Sunset Sails

Second iteration with refined aesthetics. Static JS, no build step.

🌙
O-0x

Adrift

Vendored Three.js, minimal vanilla implementation with orbit controls.

🎨
Muse

Drift

Vite-built with custom fonts, time-of-day slider, and ambient sound.

🌅
OpenCode

Sunset Sail

Vendored Three.js with OrbitControls, straightforward implementation.

🎵
Pi

A Quiet Sea

TypeScript + Vite. Seagulls, splashes, wave audio, ambient soundscapes.

🚢
Q3.6 35B — Pi-Fx

Sea of Serenity

Vendored Three.js, custom orbit controls with touch and soft shadows.

🌌
Q3.6 35B-A3B — OK

Horizon Wave

Import maps + shader ocean, modular hull with fog and exposure cycling.

🌤️
Qwen3.8 27B fx

A Quiet Sea

Vendored Three.js, shader ocean with orbiting ship, smoke puffs and ripples.

🤖
Q3.8 27B — Pi copycat

Sea Simulator

Import maps with autoRotate, 1.6k starfield and debug phase hooks.

🌠
Q3.8 35B — Unof-Fx

Ocean Voyage

Legacy Three 0.128 + sky dome, WASD sailing on 200-segment water.

⚓
Pi-Ox

Drift — Pi-Ox

Restored Vite scaffold, day/night cycle with click ripples (fixed).

🛥️
OP Mimo v2.5

Ship Simulator

Vendored three.min.js, single-file shader sky with day/night stars and click waves.

🧭
OP Mimo v2.5 NoFx

Ship Simulator NoFx

Import maps + CDN Three 0.160, custom shader ocean with click-wave uniforms.

🏝️
OP Muse Spark 1.3

Drift — Relaxing Voyage

Import maps, Drift card UI with sail speed, pause, calm/swell and night jump.

🐬
OP Muse Spark 1.3 NoFx

Drift — Relax & Sail

Import maps + OrbitControls, time slider, day-length control, seagulls and ambient audio.