# Anthropic releases Claude Fable 5.2 for all paid users and restricted Mythos 5.2 Published: 2026-11-10 Author: Keshav Aggarwal Produced: drafted with AI help from the sources it names, then checked and edited by Keshav Aggarwal. URL: https://investin.news/originals/anthropic-claude-fable-5-2-mythos-5-2 The frontier models arrive with a 20% API price cut and a split release: Fable 5.2 for paid users now, Mythos 5.2 only for vetted organisations. In short - Anthropic released Claude Fable 5.2 and Claude Mythos 5.2 on 9 November 2026. - The public version is available now on paid plans at $8 per million input tokens and $40 per million output tokens, down from $10 and $50. - Mythos 5.2 shares the same model but is limited to organisations approved for cybersecurity or biomedical research. - Anthropic says the models are up to 30% faster, with benchmark gains in coding, reasoning and vision from the company's own tests. Anthropic launched Claude Fable 5.2, plus Claude Mythos 5.2, two new frontier artificial intelligence models, on 9 November 2026. Claude's official X account said the model is now offered across all paid plans, the Claude Platform and the main cloud services, with input priced at $8 per million tokens and output at $40 per million, reduced from $10 and $50; the thread links to Anthropic's announcement. Mythos 5.2, by contrast, is restricted to vetted organisations. > Introducing Claude Fable 5.2 and Claude Mythos 5.2, designed to tackle the most daunting technical challenges. They’re capable collaborators on ambitious projects in many fields, and show improvements in areas like coding, reasoning, and vision. pic.twitter.com/jP0AutLxXb (Claude @claudeai · 9 Nov 2026 · View on X) > Claude Fable 5.2 is available today on all paid plans, on the Claude Platform, and on all major cloud platforms. It’s $8 per million input tokens and $40 per million output tokens, down from $10 and $50. Read more: https://t.co/50jMVOnsvF (Claude @claudeai · 9 Nov 2026 · View on X) ### How do the two new models differ? #### What Anthropic says the models can do > Fable 5.2 shows substantially improved skills in controlling physical robots, even on tasks it has never explicitly been trained to do. On RoboDojo, a benchmark with a simulated two-arm robot, it outperformed other models and most AI systems built to control robots. pic.twitter.com/VEiQiQrcxq (Claude @claudeai · 9 Nov 2026 · View on X) ### How developers reacted to the launch > Using log scale on the X axis is misleading though. The cost difference between High, xHigh, and Max is actually GIGANTIC! (Яosdi @rosdikuat · 10 Nov 2026 · View on X) AI Statute (@StatuendState) called the launch "a strong incremental release", saying on X that Fable 5.2 and Mythos 5.2 look like a step up on hard, long-horizon technical work rather than a general-purpose leap. > This is a strong incremental release from Anthropic. Fable 5.2 / Mythos 5.2 look like a clear step up on the hardest, longest-horizon technical work rather than a general-purpose leap.[]() The most interesting claim is the Fermat formalization: a team of… (AI Statute @StatuendState · 10 Nov 2026 · View on X) 深夜提灯人 (@bljping1) asked on X in Chinese why Anthropic recommends the previous generation. > 为啥推荐上一代呢？ (深夜提灯人 @bljping1 · 10 Nov 2026 · View on X) Keith (@Keith985211) wrote on X in Chinese that he has joined Claude Duet but finds the output speed far too slow. ### What does the launch mean for Claude users? Benchmark results for both models | What | Figure | | Fable 5.2 FrontierCode 2.0 score | 49.1% | | Claude Opus 5.5 FrontierCode 2.0 score | 45.5% | | OpenAI GPT-6 Astra FrontierCode 2.0 score | 42.8% | | Fable 5.1 FrontierCode 2.0 score at Xhigh effort | 32.4% | | Mythos 5.2 cybersecurity benchmark score | 76.3% | | Previous Mythos cybersecurity benchmark score | 61.7% | ### Claude's new models: key questions #### Is Claude Mythos 5.2 available to everyone? No. Claude Mythos 5.2 is limited to organisations approved through Anthropic's Life Sciences and Cyber Verification Programs. The public version is available now on all paid plans, the Claude Platform and major cloud platforms. #### How much does the public version cost? The public version costs $8 per million input tokens and $40 per million output tokens, down from $10 and $50 for Fable 5.1. The price applies on paid plans, the Claude Platform and major cloud platforms, according to Claude's X thread. #### What is the public version designed to do? Anthropic describes the model as built for ambitious, open-ended technical work that calls for sustained reasoning. On the company's own tests it made gains in coding, reasoning and vision, and it helped formalise the proof of Fermat's Last Theorem in 30 hours, according to Anthropic. #### Will average Claude users notice a difference? For everyday Claude subscribers, the public model is available on paid plans; Mythos 5.2 remains limited to organisations approved by Anthropic. At InvestIn.News , we think the 20% cut in API pricing matters more to most builders than the benchmark scores. The public model now charges $8 per million input tokens and $40 per million output tokens, down from $10 and $50, which makes frontier-level coding more affordable for small teams and on-chain agent developers. Splitting one underlying model into a safeguarded public version and a vetted-only Mythos is also a measured way to release risky capabilities: Fable 5.2 keeps strict cybersecurity and biology guardrails, while Mythos 5.2 stays with approved research organisations. The claimed gains, however, come from Anthropic's own evaluations. Independent tests are not yet available, so we treat the benchmark leap with appropriate caution. We will revisit this view once developers publish real-world coding results and independent labs assess the models. Sources: - Claude (@claudeai) (https://x.com/claudeai/status/2119867114450268322) - Claude (@claudeai) (https://x.com/claudeai/status/2119867138987176141) - Claude (@claudeai) (https://x.com/claudeai/status/2119867136361316437) - Claude (@claudeai) (https://x.com/claudeai/status/2119867122683953298) - Claude (@claudeai) (https://x.com/claudeai/status/2119867132452221045) - Яosdi (@rosdikuat) (https://x.com/rosdikuat/status/2119993328901230944) - AI Statute (@StatuendState) (https://x.com/StatuendState/status/2119993619327402472) - 深夜提灯人 (@bljping1) (https://x.com/bljping1/status/2119994212741722433) - Keith (@Keith985211) (https://x.com/Keith985211/status/2119993567838109810) - Maddox Schmidlkofer (@_maddox1337) (https://x.com/_maddox1337/status/2119994505118261578) - Anthropic (https://www.anthropic.com/claude-fable-and-mythos-5-2)