Claude Opus 5: what actually changed, and who should switch

Claude Opus 5 landed July 24 at $5/$25 per million tokens — the same as Opus 4.8 and exactly half of Fable 5. We break down the pricing table, the five-level effort ladder the press got wrong, Fast mode's 2.5x-for-2x tradeoff, and the ARC-verified benchmark jump.