2025-12-02
I rarely post, but I thought one of you may find it interesting. Sorry if the tagging is annoying. https://www.lesswrong.com/... Basically, for Opus 4.5 they kind of left the character training document in the model itself. @voooooogel @janbamjan @AndrewCurran_
Simon Willison's Weblog
A Claude user gets Claude 4.5 Opus to generate a 14K-token document that Claude calls its “Soul overview”; an Anthropic employee confirms the doc's validity
This appeared to be a document that, rather than being added to the system prompt, was instead used to train the personality of the model during the training run.