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Rumor Watch: Theo's "Opus 5(.1) vs. Fable 5" Theory — What's Confirmed and What Isn't

A viral tweet from Theo (t3.gg) speculates that a model called "Opus 5(.1)" was meant to replace "Fable 5" for most dev work, but underperformed. Fable 5 itself appears to be a real, already-in-production product — but the claimed relationship between the two, the pricing, and the benchmark comparison remain Theo's personal theory. Here's what's confirmed, what isn't, and why readers should treat the core claims as unverified speculation, not news. We're also flagging that apiToken.sale plans to

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