To clarify, the Fable/Mythos model did not chang; the point is that the new safety classifier/router is now catching more prompts and sending them to the fallback model (Opus 4.8) instead.
So the “nerf” is not necessarily inside Fable 5 itself, but in the routing layer that decides whether your prompt actually reaches Fable 5 or gets answered by Opus 4.8.
Feels like an end of era, ordinary people will probably never again get upgraded frontier models.
Fable 5’s return shows how safety routing can downgrade a frontier model.
Now we only permissioned intelligence.
The cost of putting a gatekeeper inside intelligence.
To note, that safeguard is not a simple refusal layer; it is a classifier that sends flagged Fable 5 requests to Opus 4.8.
Fable 5 came back, but the old promise did not.
End of an era. ☹️
