Real head-to-head · same prompt, one shot
Claude Opus 5 vs Fugu Mini
The new Anthropic flagship — benched on all 45 one-shot builds the day it landed. vs Fugu's fast mini variant — single model, no panel, ~3 min per build.
Head-to-head verdict: Claude Opus 5 wins 29–7.
What I tested — same prompt, two models
I run the same fixed prompt set through every new model the day it drops — same string, one shot, single HTML file out — and I score the result 0–10 on whether it ran, how close it hit the brief, and how good it looked. Below is what came out when I gave the exact same prompts to Claude Opus 5 and Fugu Mini, side by side, on 37 shared tasks inside the Agent Operating System.
Both models were given identical prompts inside the Agent Operating System — no help, no iteration, no "best of N" tricks. I run each prompt once, save the HTML file the model produces, and score it 0–10 on whether it ran, how close it hit the brief, and how good it looked. The scoring is mine. The verdicts below are pulled from my source comparison guides at agentos.guide where I publish every score and the reasoning behind it.
Claude Opus 5 · Benched on all 45 GoldieBench tasks via API on release day, incremental deploys as scores landed.
Fugu Mini · Dispatched from Agent OS as the fast Sakana lane. Bench scored by Claude judge against the same 42 prompts.
Side-by-side on 50 shared tasks
Click any cell to play that model's actual one-shot attempt. Medals are derived from my 0–10 scores per task (highest = 🥇, second = 🥈, third = 🥉).
Task ↓
Claude Opus 5
Fugu Mini
Game
Game
Game
Game
Game
Game
Game
Game
Game
Game
Game
Game
Game
Game
Page
Page
Sim
Sim
Sim
Sim
Sim
Sim
Sim
Sim
Where Claude Opus 5 beat Fugu Mini
The tasks where I gave Claude Opus 5 a higher 0–10 score on the same prompt — with the actual commentary from my source guides.
Dogfight
Game
Claude Opus 5 8.4
·
Fugu Mini 6.0
(+2.4)
· polished flight sim
What I saw: Gorgeous low-poly jet, layered HUD, radar with 4 bogeys, gradient sky and terrain with pull-up warning all render cleanly and read as a real dogfight sim; slightly short of top since the screenshot shows enemies only as radar dots rather than visible in-air combat/tracers, and sc…
Galaxy
Sim
Claude Opus 5 8.8
·
Fugu Mini 6.5
(+2.3)
· Gorgeous spiral vortex
What I saw: Stunning multi-arm spiral with a glowing core, gradient star coloring (gold→pink→blue), halo, and distant starfield — visually the strongest galaxy render, backed by rich swirl/orbit/zoom/supernova interaction. Only nit is FPS at 39, but the composition clearly matches or beats t…
Rpg
Game
Claude Opus 5 8.7
·
Fugu Mini 6.5
(+2.2)
· Polished 3D RPG
What I saw: Strong: gorgeous low-poly 3D world with a real armored player, visible sword-wielding enemies, full HUD (HP/stamina/souls, kills/threats/gold), inventory hotbar and functional minimap all rendering cleanly. Weak: it's more third-person action-RPG than classic top-down sprite RPG,…
Webos
Page
Claude Opus 5 8.7
·
Fugu Mini 6.5
(+2.2)
· 3D glass desktop
What I saw: Stunning execution: glassmorphic windows with mac-style traffic-light controls, three live apps stacked (Notes/Paint/Terminal), functional dock, menubar clock, and a gorgeous animated Three.js background of shaded/wireframe solids — clearly matches or beats the field's best. Only…
Aurora
Visual
Claude Opus 5 8.6
·
Fugu Mini 6.5
(+2.1)
· cinematic aurora scene
What I saw: Gorgeous WebGL curtains with realistic vertical streaks, layered mountains, starfield and water reflection make this a full cinematic scene; polished palette switcher and typography plus reflection depth push it past the field's best.
Where Fugu Mini beat Claude Opus 5
The tasks where I gave Fugu Mini a higher 0–10 score on the same prompt — with the actual commentary from my source guides.
Arcade
Game
Fugu Mini 8.5
·
Claude Opus 5 6.5
(+2.0)
What I saw: 55KB Breakout-style — paddle, ball, brick wall, particles, score HUD. Smoke-test PASS (large pixel diff after input).
Doom
Game
Fugu Mini 8.0
·
Claude Opus 5 6.8
(+1.2)
What I saw: Doom-style raycaster FPS with sprite enemies. Smoke-test PASS (pixel change after click+keys).
Neoncity
Game
Fugu Mini 8.5
·
Claude Opus 5 7.4
(+1.1)
What I saw: Cyberpunk neon city flythrough. Smoke-test PASS (9.6% pixel diff — strong motion).
Game
Game
Fugu Mini 9.0
·
Claude Opus 5 8.4
(+0.6)
· winner · biggest visual change
What I saw: Juicy browser game. Smoke-test PASS with 55% pixel diff — most reactive build in the sweep.
Voxel
Visual
Fugu Mini 8.5
·
Claude Opus 5 8.2
(+0.3)
What I saw: Mini gap-fill (round 2) — Temple-Run voxel runner. Smoke-test PASS with 17.0% pixel diff — works this time (the earlier Mini voxel was STATIC and got deleted).
Strengths & weaknesses I logged
Claude Opus 5
Strengths
- Frontier-class coding + agentic reasoning (Claude 5 family)
- 1M-token context — reads an entire codebase in one call
- Benched here with skill-infused game prompts the day of release
Trade-offs
- Premium pricing ($5/$25 per M) — route the everyday 90% to cheaper lanes
- Reasoning-by-default eats token budgets unless tuned per call
Fugu Mini
Strengths
- Zero panel orchestration — much lower latency than Ultra
- Same Sakana subscription, no extra cost
- Doesn't time out on heavy game/3D prompts where Ultra stalls
Trade-offs
- Single model only — no ensemble verdict
- Newer than Ultra — less calibration / verification
Pricing & context — the spec sheet
| Spec | Claude Opus 5 | Fugu Mini |
|---|---|---|
| Vendor | Anthropic | Sakana AI |
| Context window | 1,000,000 tokens | Single-model variant of Sakana's Fugu — no panel orchestration. Same API endpoint, much faster per call. |
| Price | $5 / $25 per M | Same Sakana subscription pool as Fugu Ultra |
| Pricing detail | Anthropic's brand-new flagship — the first Opus of the Claude 5 family, with a 1M-token context window. Benched via API the day it dropped; game tasks use our skill-infused AAA build prompts. | The non-Ultra `fugu` model on Sakana's API. Sakana describes it as 'Fast mini model optimized for low latency yet high quality responses.' Crucially: zero orchestration tokens per call (vs Ultra's panel of thousands). Returns in ~3 min instead of 6-15 min and doesn't time out on heavy prompts. |
| Release | 2026-07 | 2026-06-15 |
| Bench coverage | 50/50 scored · avg 8.27/10 | 36/37 scored · avg 7.75/10 |
The verdict — which should you pick?
Across 36 scored shared tasks, Claude Opus 5 averaged 8.37/10, beating Fugu Mini's 7.75/10 by 0.62 points. Pick Claude Opus 5 when the build has to ship on the first prompt and you can afford the trade-offs in the comparison below.
If you only run one of these inside your stack, the head-to-head average above is the call. If you can run both, my honest play is to wire Claude Opus 5 and Fugu Mini both into the Agent Operating System and dispatch each from the kanban by task type — hardest agentic builds → Claude Opus 5, agent loops where latency matters more than panel consensus → Fugu Mini. That's the same setup I run for the 4,000+ founders inside the AI Profit Boardroom.
FAQ — Claude Opus 5 vs Fugu Mini
Which is better, Claude Opus 5 or Fugu Mini?
On Goldie Bench, Claude Opus 5 averages 8.37/10 across the shared tasks, with 13 gold, 7 silver, 5 bronze overall. Fugu Mini averages 7.75/10, with 2 gold, 0 silver, 1 bronze. Claude Opus 5 wins the head-to-head 29–7.
How much does Claude Opus 5 cost vs Fugu Mini?
Claude Opus 5: Anthropic's brand-new flagship — the first Opus of the Claude 5 family, with a 1M-token context window. Benched via API the day it dropped; game tasks use our skill-infused AAA build prompts. Fugu Mini: The non-Ultra `fugu` model on Sakana's API. Sakana describes it as 'Fast mini model optimized for low latency yet high quality responses.' Crucially: zero orchestration tokens per call (vs Ultra's panel of thousands). Returns in ~3 min instead of 6-15 min and doesn't time out on heavy prompts.
What's the context window for Claude Opus 5 vs Fugu Mini?
Claude Opus 5 has a 1,000,000 tokens context window. Fugu Mini has a Single-model variant of Sakana's Fugu — no panel orchestration. Same API endpoint, much faster per call. context window.
When should I pick Claude Opus 5 over Fugu Mini?
Pick Claude Opus 5 for: Hardest agentic builds; Whole-repo reasoning; Frontier one-shots. The trade-off is the weaknesses we logged on the bench: Premium pricing ($5/$25 per M) — route the everyday 90% to cheaper lanes; Reasoning-by-default eats token budgets unless tuned per call.
When should I pick Fugu Mini over Claude Opus 5?
Pick Fugu Mini for: Agent loops where latency matters more than panel consensus; Quick first-drafts you'll refine downstream; Filling out a bench when Ultra is timing out. The trade-off is the weaknesses we logged on the bench: Single model only — no ensemble verdict; Newer than Ultra — less calibration / verification.
How does Goldie Bench score Claude Opus 5 vs Fugu Mini?
Every demo on this page was built by Julian Goldie inside the Agent Operating System — same fixed prompt for both models, one shot, single HTML file out. Each result gets a 0–10 score on whether it ran, how close it hit the brief, and how good it looked. The highest score on each task gets gold; second gets silver; third gets bronze. See methodology for full provenance.
Related comparisons
Other head-to-heads using the same scoring system:
Claude Opus 5 vs Fusion Fugu Mini vs Fusion Claude Opus 5 vs Hermes MoA Fugu Mini vs Hermes MoA Claude Opus 5 vs GPT-5.6 Sol Fugu Mini vs GPT-5.6 Sol Claude Opus 5 vs Claude Fable 5 Fugu Mini vs Claude Fable 5Full model pages: Claude Opus 5 · Fugu Mini · back to the leaderboard
The same stack Julian uses
Run this stack yourself.
Every demo on this bench was built inside the Agent Operating System — one prompt, one shot, single HTML file out. The Agent OS, the prompts, the templates, the weekly walkthroughs and 4,000+ founders shipping with it every day all live inside the AI Profit Boardroom.
4,000+founders
258documented wins
38countries
$59/momonthly