Ask HN: Is Claude Fable 5 built from scratch or just better data?

A Hacker News user questioned whether Anthropic's Claude Fable 5 represents a new architecture trained from scratch or merely improved fine-tuning on Opus 4.8, noting the model's "version 5" label lacks a corresponding Fable-4 predecessor. The inquiry highlights confusion over the model's technical lineage and the significance of its versioning.

| |||||||||||| 1 point by | I am trying to understand why Claude Fable 5 is different, is it a new architecture, or trained from scratch or just a better fine tuning on top of Opus 4.8? Why is it labeled as new type of model with a version 5? We don't have Fable-4, what does it compare to? | ||||||||||| |