Anthropic Announces Claude Fable and Mythos 5.2 Models

Anthropic has launched the Claude Fable 5.2 and Claude Mythos 5.2 models, designed to overcome complex technical challenges. As successors to the 5.1 versions released in September, these new models promise improvements in speed and performance across coding, reasoning, and visual processing.

Claude Fable 5.2 has been specifically optimized for software engineering problems, the management of long-term projects, and the coordination of agent teams. The company stated that in preliminary tests, the model solved two open problems related to black hole physics and formalized the proof of Fermat's Last Theorem within 30 hours.

According to data shared by Anthropic, the new models also assisted in designing three different electronic devices from scratch and executing complex software migrations. While Claude Fable 5.2 is available as of today, an exclusive access strategy is being followed for Claude Mythos 5.2, limited to approved organizations.