To summarize: the classifiers Anthropic puts in front of Fable are way, way too zealous and have way too many false positives.

From my experience, the model itself is very useful when it isn't refusing any of your prompts.

It is, but it's also using tokens at absurd rate, I asked it to review the planned architecture for a medium scale project and it used my 5 hours limit on one prompt just zaaaaap, not even the fable limit straight up the full 5 hour session no more Claude for the afternoon thank you for paying you Max x20 sub. Hell it didn't even bother to finish produce anything worthwhile.

And just to be clear, plan was already done, just had to review it, it got opus 4.8 Max and gpt 5.5 Extra High validated already and they didn't use much resource for it so I just don't get it. I guess they want to use it as a way to feed the extra credit money income.

I'm using a homemade ai consensus thing for planning and I wanted to add fable to it but forget it.

Or maybe I should use fable in low effort reasoning mode and it will be better than opus 4.8 at max ?

Thanks - that's a good phrase we can use to replace the baity title. I've done so above.

(Normally we prefer to find a representative phrase from the article itself, but I found that too daunting and gave up.)

How do you know? Is it really that obvious of a tell between Opus and Fable? My understanding is that they silently downgrade you.