Jamieson O'Reilly @theonejvo

Did I just unlock claude-fable-5-lite? 😂

Since Fable 5 got pulled (US export control order, Anthropic is contesting it), I wanted to see how much of its character lives in the system prompt vs. the model itself.

I ran the leaked Fable 5 prompt on Opus 4.8 head-to-head against stock 4.8.

Jun 13, 2026 View on X →

https://x.com/theonejvo/status/2065816283476824126