Mythos 5.1, Fable 5.1 and Opus 5.5: Model Welfare

If you are familiar with my previous posts on model welfare for new Claude models, you can skip the Introduction and The Story So Far. This post goes over model welfare and related concerns, the same way I previously did for Fable and Mythos 5, Opus 5, Opus 4.8 and Opus 4.7. Events overtook me before I could post this for Mythos and Fable 5.1, so I am combining the reports there with the one for Opus 5.5, along with selected other related observations. Model Welfare: The Story So Far (As Per Fable Model Welfare Post). Everything impacts everything.

First reported by Don't Worry About the Vase. This page is a short excerpt; the full text is theirs.