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Claude Opus 5: The System Card
Claude Opus 5 is trying to be the best of both worlds. On many practical tasks, Opus 5 is pitched as straight up as good or better than Fable 5, while being faster, at half the price. Most tasks do not require Mythos-level big model smell. Claude Opus 5 is substantially stronger than Claude Opus 4.8 across the board, w