Anthropic Releases Claude Fable 5.2 and Claude Mythos 5.2 Models
Anthropic released two new models, Claude Fable 5.2 and Claude Mythos 5.2, stating that both have improvements in coding, reasoning, and vision, and that generation speed is also faster than version 5.1. Claude Fable 5.2 launches today and excels at handling highly difficult software engineering problems; it can orchestrate teams of agents and take on long-horizon projects. Claude Mythos 5.2 is initially available only to vetted organizations. Anthropic said that in pre-release testing, the two models completed software migrations that were previously difficult to achieve, designed three working electronic devices from scratch, solved two open problems in black hole physics, and formally proved Fermat's Last Theorem within 30 hours.
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Anthropic simultaneously released two 5.2 models and provided a specific task list from pre-release testing, which can be used to assess their capability positioning and scope of availability.
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Anthropic is announcing two new models today: Claude Fable 5.2 and Claude Mythos 5.2, which it says are designed to take on “daunting” technical challenges. The company claims the new models show improvements in coding, reasoning, and vision, and can generate outputs faster than the 5.1 versions of the Fable and Mythos models.
Claude Fable 5.2 is good at challenging software engineering problems, Anthropic says, and can orchestrate agent teams and tackle long-running projects. The new model has also solved some complex scientific problems, including two open theoretical physics problems.
During prerelease testing, the two models have “helped our engineers complete otherwise-infeasible software migrations, designed three working electronic devices from scratch, solved two open problems in the physics of black holes, made substantial progress on robotics evaluations, and formalized the proof of Fermat’s Last Theorem in 30 hours,” Anthropic says.
Claude Fable 5.2 is launching today. As for Claude Mythos 5.2, only vetted organizations will have access to start. The new 5.2 models follow the release of Claude Fable 5.1 and Claude Mythos 5.1 in September .