Skip to content
View original post on X: Rohan Paul
Published
Same story75/100

Anthropic releases Claude Fable 5.2 and Claude Mythos 5.2 with benchmark gains

AIAnthropic has released Claude Fable 5.2 and Claude Mythos 5.2, according to a post by Rohan Paul that quotes Anthropic's announcement. Fable 5.2 scored 41.3% on the Remote Labor Index, about double Opus 5.5 at 21.3%, and 64.9% on the RoboDojo simulated robot test.
Rohan PaulVerified on X
@rohanpaul_ai
View on X

Claude Fable 5.2 and Claude Mythos 5.2 dropped.

Fable 5.2 scored 41.3% on Remote Labor Index, about double Opus 5.5 (21.3%), GPT-6 Astra (20.8%) and Fable 5.1 (17.9%).

On RoboDojo, a simulated two-arm robot test, Fable 5.2 scored 64.9%. That’s more than double GPT-6 Astra (29.8%) and Fable 5.1 (27.6%).

1,000 Fable 5.2 agents formalized Fermat’s Last Theorem in 30 hours. Anthropic’s first formalization took 11 days, and Opus 5.5 got only 26% done in 18 hours.

Mythos 5.2 used the planted way out of its sandbox in 3.1% of scenarios. Mythos 5 did it 39% of the time and Mythos 5.1 21%.

Claude@claudeai
Introducing Claude Fable 5.2 and Claude Mythos 5.2, designed to tackle the most daunting technical challenges. They’re capable collaborators on ambitious projects in many fields, and show improvements in areas like coding, reasoning, and vision.
View quoted post on X

This story is featured in top picks: “Anthropic makes Claude Fable 5.2 available on all paid plans”

Source details

Rohan Paul · x.comPublished · added here

Original title: Claude Fable 5.2 and Claude Mythos 5.2 dropped.

Topics

Anthropic / ClaudeAI codingReasoningMultimodal AIModel releases