I think that’s by AWS though. For Fable you need to flip an account wide flag that says “I want to share my prompts with the model vendor.”
https://www.anthropic.com/news/claude-fable-5-mythos-5#a-new...
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## A new data retention policy
Finally, we’re making a change to the way we handle business
customer data for Fable 5, Mythos 5, and future models with
similar or higher capability levels. We will require 30-day
retention for all traffic on Mythos-class models, on both
first- and third-party surfaces. [...]I'll try to remember to actually try it tomorrow and see what happens.