In 30 seconds
In this June 2026 video, Theo argues that restrictions around Anthropic's Fable model limit who can use it and complicate evaluation. He cites benchmark results that use an Opus fallback and a report of refusals on ProgramBench, and criticizes the precedent he believes the restrictions set.
- 1A powerful model with access limitsTheo praises Fable's capabilities but criticizes how Anthropic implemented access restrictions.
- 2Benchmark fallback mattersHe notes that strong reported results can include an Opus 4.8 fallback rather than Fable alone.
- 3ProgramBench refusalsHe cites a reported run in which Fable refused all 200 tasks, and argues that restrictions affect evaluation.
Takeaways
- Theo says some people could not access Fable at the time of the video.
- Some benchmark results for Fable included an Opus 4.8 fallback.
- Theo cites a report that Fable refused all 200 tasks in a ProgramBench run.
- He argues that the restrictions set a troubling precedent for future models.
Read the edited text by chapter
Access and benchmark restrictions
Theo criticizes the limits on who can use Fable. He also examines benchmark results and the role of a fallback model.
Fable, Anthropic's new Mythos-class model, is powerful, but at the time of this video some people cannot use it at all. I think the way Anthropic implemented these restrictions is unacceptable.
The model has benchmarked very well, but some results come with a qualification: an Opus 4.8 fallback. In another example, a reported ProgramBench run says Fable refused all 200 tasks. I find the restrictions absurd, and I worry about the precedent they set.
Refusals and precedent
He cites reported refusals on ProgramBench. He worries about the precedent set by such restrictions.
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