Claude Fable 5.2 (Max) by @AnthropicAI ranks #1 on Agent Arena, ahead of Claude Opus 5.5 (Max) in 9 of the 10 categories where both are ranked. In the 10th category, there is a statistical tie.

Where Fable really shines over Opus is its visual taste.

Net improvement score for Fable 5.2 vs. Opus 5.5 (both Max) across key categories:

• Overall: 30.48% vs. 19.51%
• Visual design: 45.34% vs. 23.29%
• Documents: 31.51% vs. 17.88%
• Knowledge work: 25.67% vs. 13.24%
• Code: 31.45% vs. 22.24%

In Business & Finance, the gap is too small to call.

But the scores only show that Fable is ahead, not where the gap comes from. So we looked at what makes Fable 5.2 different from Opus 5.5 across real-world sessions.