Related, from Ethan Mollick:
“One thing I mentioned only in passing in my Fable post is that, for long running tasks, Fable starts to develop its own dialect as its many agents and tasks reinforce themselves and make Claudish language ever more Claudish.
You need to ask it to report out in plain English.
This was after a 9 hour task, and it all makes sense, actually, but takes way too much effort to parse, like reading Shakespearian English.”

The United States Government has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States. This includes Anthropic employees who are foreign nationals.
Anthropic is currently disabling Fable 5 and Mythos 5 for all customers.
https://www.anthropic.com/news/fable-mythos-access