Real head-to-head · same prompt, one shot
Claude Fable 5 vs Claude Opus 5
The newest Anthropic model — first Mythos-class made generally available. vs The new Anthropic flagship — benched on all 45 one-shot builds the day it landed.
Head-to-head verdict: Claude Fable 5 wins 9–4.
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 Fable 5 and Claude Opus 5, side by side, on 22 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 Fable 5 · Selected from Agent OS for the highest-stakes work — it replaced Opus 4.8 as the safety net on hard prompts. Its four core 3D games were rebuilt to showcase quality with the threejs-game-director skill, lifting the full 42-task bench to 8.14 avg — the #1 solo model, behind only the Fusion and MoA ensembles.
Claude Opus 5 · Benched on all 45 GoldieBench tasks via API on release day, incremental deploys as scores landed.
Side-by-side on 47 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 = 🥉).
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Claude Opus 5
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Where Claude Fable 5 beat Claude Opus 5
The tasks where I gave Claude Fable 5 a higher 0–10 score on the same prompt — with the actual commentary from my source guides.
Crypt
Game
Claude Fable 5 8.8
·
Claude Opus 5 2.0
(+6.8)
What I saw: AAA rebuild via the threejs-game-director skill transforms it into a real torch-lit crawler: warm-lit cracked-stone walls, a stone sarcophagus, a flaming torch held in first-person, scattered rubble and soul-gem pickups, drifting dust, and a cohesive HUD (vitality, objective + di…
Neonracer
Game
Claude Fable 5 8.3
·
Claude Opus 5 2.0
(+6.3)
· polished neon racer
What I saw: Renders cleanly with strong on-brief neon aesthetic — glowing pink/cyan road edges, retro grid, colorful pylons and dashes create a convincing synthwave scene. Weaknesses: the vapor trail particles aren't clearly visible in the shot and the player car is a bit blocky, keeping it …
Game
Game
Claude Fable 5 7.8
·
Claude Opus 5 2.5
(+5.3)
What I saw: Clean 3D neon arena renders well with polished glowing walls, floating gold orbs, red chasers, and complete mechanics (score/lives/invuln/restart), but it's a fairly familiar collect-and-dodge concept that lands just short of the field's best.
Flightsim
Game
Claude Fable 5 8.0
·
Claude Opus 5 3.0
(+5.0)
What I saw: One-shot: real aircraft model (wings/prop/gear) on runway w/ centerline + edge lights + tower, complete glass PFD (speed/alt tapes, pitch ladder, heading ribbon), autopilot demo rolls. Alt tape shows negative rows. Eyeballed.
Gtafoot
Game
Claude Fable 5 7.5
·
Claude Opus 5 2.5
(+5.0)
What I saw: One-shot: night city w/ dense lit windows, DINER neon, rain streaks, lamp pools, blocky humanoid player, cohesive HUD + minimap + wanted stars. Dark at street level but atmospheric. Eyeballed.
Where Claude Opus 5 beat Claude Fable 5
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
·
Claude Fable 5 7.4
(+1.0)
· polished 3D flight sim
What I saw: Gorgeous detailed player jet, full flight HUD, functional radar showing 4 bogeys, terrain warning, and afterburner/boost systems all read as a shippable 3D dogfighter. Slightly held back because the screenshot shows no visible enemy aircraft in view or active combat/tracers, leav…
Gtadrive
Game
Claude Opus 5 8.4
·
Claude Fable 5 7.5
(+0.9)
· polished neon driving
What I saw: Gorgeous cohesive art direction — detailed low-poly car with wheels/shadow, layered cityscape, refined HUD with integrity/velocity/wanted stars and a live minimap showing cop (red) and player markers plus traffic (purple car visible). Pursuit=2 and full control set (fire/steal/bo…
Dragonflight
Game
Claude Opus 5 8.2
·
Claude Fable 5 7.4
(+0.8)
What I saw: Gorgeous stylized dragon with articulated wings, spine and belly plates plus a polished full HUD (hull/fury/alt/spd/combo, rings, kills, hostiles, distance marker) — clearly shippable and combat-ready with 5 hostiles tracked. Held back from the top by no visible neon rings or ene…
Dragonrealm
Game
Claude Opus 5 8.3
·
Claude Fable 5 7.8
(+0.5)
What I saw: Gorgeous atmospheric frozen world — aurora, moon glow, snowy terrain, low-poly pines, ruins, and a well-modeled armored third-person character with sword DRAWN and full HUD (compass, health/stam, kill counter). Strong and clearly shippable, but no visible enemies/dragon or combat…
Strengths & weaknesses I logged
Claude Fable 5
Strengths
- Now the top SOLO model on this bench — 8.14 avg, #3 overall, edging Grok (8.13); only the Fusion (8.60) and Hermes MoA (8.38) ensembles rank higher
- 15 medals across 42 tasks (5 gold, 2 silver, 8 bronze) — shader/GPU physics is its superpower (Cornell-box path tracer 8.7, black-hole lensing 8.7, synthwave outrun 8.7)
- Its four core 3D games (crypt, skyrim, twilightvale, voxelcraft) rebuilt to showcase quality with the threejs-game-director skill — authored heroes, layered worlds, PBR materials, cohesive HUDs, all 8.8–9.0
- Beats Opus 4.8 head-to-head on the majority of tasks; tops external SWE-bench Verified at 95.0% in Julian's three-dragons writeup
Trade-offs
- Its hardest one-shots (crypt, twilightvale) black-screened on three.js r128 API drift — the scored builds are agentic rebuilds, not the raw first pass, and crypt's AAA rebuild needed a one-line emissive patch
- The showcase ceiling shown here needs the threejs-game-director scaffolding baked into the prompt — a bare one-shot lands lower (7.72 avg)
- Premium $10/$50 per-M pricing — you're paying for reasoning depth; cheaper models stay competitive on pure one-shot visuals
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
Pricing & context — the spec sheet
| Spec | Claude Fable 5 | Claude Opus 5 |
|---|---|---|
| Vendor | Anthropic | Anthropic |
| Context window | 200,000 tokens (1M with extended thinking) | 1,000,000 tokens |
| Price | $10 / $50 per M tokens | $5 / $25 per M |
| Pricing detail | Released alongside Mythos 5 on June 9, 2026 as the publicly-available member of the new Mythos class. Premium per-token pricing on the Anthropic API; available everywhere Opus 4.8 ships. | 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. |
| Release | 2026-06-09 | 2026-07 |
| Bench coverage | 47/47 scored · avg 8.10/10 | 13/22 scored · avg 5.60/10 |
The verdict — which should you pick?
Across 13 scored shared tasks, Claude Fable 5 averaged 7.95/10, beating Claude Opus 5's 5.60/10 by 2.35 points. Pick Claude Fable 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 Fable 5 and Claude Opus 5 both into the Agent Operating System and dispatch each from the kanban by task type — mission-critical one-shot builds where you want anthropic's newest reasoning → Claude Fable 5, hardest agentic builds → Claude Opus 5. That's the same setup I run for the 4,000+ founders inside the AI Profit Boardroom.
FAQ — Claude Fable 5 vs Claude Opus 5
Which is better, Claude Fable 5 or Claude Opus 5?
On Goldie Bench, Claude Fable 5 averages 7.95/10 across the shared tasks, with 4 gold, 2 silver, 1 bronze overall. Claude Opus 5 averages 5.60/10, with 0 gold, 0 silver, 1 bronze. Claude Fable 5 wins the head-to-head 9–4.
How much does Claude Fable 5 cost vs Claude Opus 5?
Claude Fable 5: Released alongside Mythos 5 on June 9, 2026 as the publicly-available member of the new Mythos class. Premium per-token pricing on the Anthropic API; available everywhere Opus 4.8 ships. 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.
What's the context window for Claude Fable 5 vs Claude Opus 5?
Claude Fable 5 has a 200,000 tokens (1M with extended thinking) context window. Claude Opus 5 has a 1,000,000 tokens context window.
When should I pick Claude Fable 5 over Claude Opus 5?
Pick Claude Fable 5 for: Mission-critical one-shot builds where you want Anthropic's newest reasoning; Long-context work using extended thinking up to 1M tokens; Plan-heavy multi-step tasks where intelligence in the plan matters more than the build. The trade-off is the weaknesses we logged on the bench: Its hardest one-shots (crypt, twilightvale) black-screened on three.js r128 API drift — the scored builds are agentic rebuilds, not the raw first pass, and crypt's AAA rebuild needed a one-line emissive patch; The showcase ceiling shown here needs the threejs-game-director scaffolding baked into the prompt — a bare one-shot lands lower (7.72 avg); Premium $10/$50 per-M pricing — you're paying for reasoning depth; cheaper models stay competitive on pure one-shot visuals.
When should I pick Claude Opus 5 over Claude Fable 5?
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.
How does Goldie Bench score Claude Fable 5 vs Claude Opus 5?
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 Fable 5 vs Fusion Claude Opus 5 vs Fusion Claude Fable 5 vs Hermes MoA Claude Opus 5 vs Hermes MoA Claude Fable 5 vs GPT-5.6 Sol Claude Opus 5 vs GPT-5.6 Sol Claude Fable 5 vs Qwen 3.8 Claude Opus 5 vs Qwen 3.8Full model pages: Claude Fable 5 · Claude Opus 5 · 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