
Fable 5 Outperforms GPT-5.6 Sol on NP-Hard Problem, /goal Not a Game Changer
A new benchmark pits Claude Fable 5 against GPT-5.6 Sol on an unpublished NP-hard optimization problem. Fable 5 produced the best overall solution and showed remarkable consistency. The native /goal mode helped in most trials but made average performance worse for both models, revealing that persistence features can amplify both good and bad decisions.








