Free prompt · Prompts & Workflows

Opus 5 vs Fable 5: The four one-shot test prompts

The four full physics-demo prompts from the Opus 5 vs Fable 5 test. Paste each into both models, no follow-ups, compare the builds.

Charlie Hills Added 24 July 2026 · Free

What’s inside

1The test in one picture
2Run order and timings
31 · The wind tunnel
42 · The gravity sandbox
53 · The double pendulum
64 · Inside the Earth

The test in one picture

!The one-prompt test, how to run it

That’s the first part. The rest of this guide is free too.

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