Anthropic launches Fable 5.2 and Mythos 5.2 with different safeguards
Anthropic says the models deliver faster responses, while access to Mythos is limited to specific programs and enterprise plans.
Anthropic has launched Claude Fable 5.2 and Claude Mythos 5.2, claiming gains in coding, reasoning and vision. The company says both communicate more clearly than their 5.1 predecessors and generate output up to 30 percent faster.
Although they use a common underlying model, the two versions have different restrictions. Publicly available Fable includes safeguards intended to prevent cybersecurity and biology misuse. Mythos does not carry the same restrictions; access comes through Anthropic's Life Sciences and Cyber Verification Programs or Claude Security on Enterprise plans.
Benchmarks indicate advantages over Opus 5.5 in fields including cybersecurity, computer use and multidisciplinary reasoning. Anthropic also reports that Fable 5.2 requires fewer tokens for challenging work at the medium effort setting than Fable 5.1.
Availability for Fable 5.2 extends to every platform. Its allowance reaches up to 50 percent of the weekly usage limit on Pro plans and standard Team seats. A fast mode can increase token-generation speed by up to 2.5 times through Microsoft Foundry, Claude Code, the Claude Platform and Claude Models on Google Cloud.
