Anthropic's Claude Fable 5.2 and Mythos 5.2 AI Models Are Now Available in Microsoft Foundry

Microsoft is bringing Anthropic’s latest frontier AI models to Microsoft Foundry, giving developers and businesses more powerful tools. The new Claude Fable 5.2 and Mythos 5.2 models target demanding work across software engineering, cybersecurity, scientific research, and finance.

Claude Fable 5.2 is built for complex engineering and research

Microsoft announced the new models’ availability in Foundry as soon as they were announced by Anthropic yesterday. The company describes them as its most capable generally available models for technical fields.

One of the highlights of the models is that they can handle large software projects across multiple repositories. Fable 5.2 can investigate difficult engineering problems, make architectural decisions, test changes, and revisit earlier assumptions when something doesn’t add up.

Interestingly, Anthropic says the model can work through ambiguous engineering tasks for hours or even days. It can coordinate multiple subagents and flag results that cannot be reproduced. This could make it useful for developers handling projects that require several rounds of implementation and verification. In addition, Fable 5.2 can help formalize mathematical proofs, tackle difficult physics computations, and investigate complicated financial scenarios.

Mythos 5.2 brings specialized AI capabilities

Meanwhile, Claude Mythos 5.2 targets cybersecurity and life sciences. Microsoft says it supports authorized security teams working on system hardening, undocumented software, and vulnerability analysis. For researchers, Mythos 5.2 can synthesize scientific literature, coordinate analyses, and support biomolecular design. Access is restricted to authorized customers through Anthropic’s verification programs.

Pricing, availability, and safety controls

Claude Fable 5.2 is priced $8 per million input tokens and $40 per million output tokens. The Fast version doubles those rates to $16 and $80, respectively. Both models are generally available through Microsoft Foundry and hosted on Anthropic. Microsoft also highlights additional safeguards against misuse in cybersecurity and biology. Certain blocked requests receive responses from alternative Claude models instead. Lastly, it should be noted that Mythos access requires customers to contact their Microsoft account team.