Anthropic Unveils Faster, Cheaper Claude Fable 5.2 and Mythos 5.2 AI Models

Anthropic has launched Claude Fable 5.2 and Claude Mythos 5.2, its most powerful AI models to date. Both models are faster and cheaper than their predecessors. The company claims they can complete tasks such as building an operating system in eight days and solving Fermat's Last Theorem in 30 hours.

Fable 5.2 is available to all users through Claude apps, Claude Code, the API, and major cloud platforms including Amazon Web Services, Google Cloud, and Microsoft Azure. On Pro and standard Team plans, Fable can account for up to 50 percent of weekly usage limits. Mythos 5.2 is reserved for vetted organizations and comes without the cybersecurity and biology restrictions applied to Fable.

“Fable and Mythos are the same model with different safeguards.”

Prices have fallen by 20 percent compared with the previous generation. Fable 5.2 and Mythos 5.2 cost 7.19 euros per million input tokens and 35.94 euros per million output tokens. The previous Fable 5.1 and Mythos 5.1 cost 8.98 euros and 44.92 euros respectively.

An optional fast mode generates responses up to 2.5 times faster but costs twice as much. In fast mode, input tokens cost 14.38 euros per million and output tokens cost 71.88 euros per million. This mode is available in Claude Code and on Google and Microsoft clouds.

Anthropic says Fable 5.2 produces about 55 percent fewer unnecessary blocks than Fable 5.1. However, Fable still blocks most cybersecurity and biology tasks, routing those requests to older Opus models. Mythos 5.2 has no such blocks.

The launch comes shortly before Anthropic's initial public offering on the Nasdaq, for which the company is courting investors. Independent testing also places Fable 5.2 in the lead on the Intelligence Index from Artificial Analysis.