{"id":14855,"date":"2026-06-09T10:19:00","date_gmt":"2026-06-09T17:19:00","guid":{"rendered":"https:\/\/www.runwayritz.com\/index.php\/2026\/06\/09\/anthropic-recently-released-a-mythos-class-ai-model-called-claude-fable-details-here\/"},"modified":"2026-06-09T10:23:45","modified_gmt":"2026-06-09T17:23:45","slug":"anthropic-recently-released-a-mythos-class-ai-model-called-claude-fable-details-here","status":"publish","type":"post","link":"https:\/\/www.runwayritz.com\/index.php\/2026\/06\/09\/anthropic-recently-released-a-mythos-class-ai-model-called-claude-fable-details-here\/","title":{"rendered":"Anthropic recently released a Mythos-class AI model called Claude Fable, details here"},"content":{"rendered":"<p><br \/>\n<\/p>\n<div>\n<figure class=\"img-border featured-image\">\n<\/figure>\n<p class=\"wp-block-paragraph\">Back in April, Anthropic unveiled its Claude Mythos AI model that it says is too powerful to be released publicly. Instead, the company shared access with software vendors, including Apple, in an effort to use the model to improve online security.<\/p>\n<p class=\"wp-block-paragraph\">Now, as promised, Anthropic has released what it calls a Mythos-class model that customers can actually use. The new model is called Claude Fable.<\/p>\n<p><span id=\"more-1055846\"\/><\/p>\n<h2 id=\"h-claude-fable-5-and-claude-mythos-5\" class=\"wp-block-heading\">Claude Fable 5 and Claude Mythos 5<\/h2>\n<p class=\"wp-block-paragraph\">Anthropic calls the Claude Fable 5 its first Mythos-class model publicly available to customers. <\/p>\n<p class=\"wp-block-paragraph\">&#8220;The capabilities of the Fable 5 exceed those of any model we&#8217;ve ever made available,&#8221; the company said. &#8220;It ranks high in almost all tested benchmarks of AI capability, showing impressive performance in software engineering, knowledge work, vision, scientific research, and many other areas. When the task is long and complex, Fable 5 leads above our other models.&#8221;<\/p>\n<p class=\"wp-block-paragraph\">Anthropic adds that its new Claude Fable 5 model comes with some protections, given its power:<\/p>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Releasing a capable model comes with risks. Without defenses, Fable 5&#8217;s abilities in areas like cybersecurity can be misused to cause serious damage. We have therefore introduced a model with protections which means that questions on certain topics will find an answer in our most powerful model, the Claude Opus 4.8. To release the model safely and quickly, we tuned these protections carefully\u2014sometimes they will catch harmless requests, although they start, on average, in less than 5% of sessions. With more capable models coming in the coming months, we are working to improve our defenses and reduce false positives as quickly as possible.<\/p>\n<\/blockquote>\n<p class=\"wp-block-paragraph\">Beyond Claude Fable 5, Anthropic also details Claude Mythos 5, which is basically Fable 5 without many protections. Mythos 5 is only available to &#8220;a small group of cyberdefenders and infrastructure providers,&#8221; according to Anthropic. <\/p>\n<figure class=\"wp-block-embed alignwide is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<p><div class=\"youtube-embed\" data-video_id=\"Y9Wz2PV404E\"><iframe loading=\"lazy\" title=\"Introducing Claude Fable 5\" width=\"696\" height=\"392\" src=\"https:\/\/www.youtube.com\/embed\/Y9Wz2PV404E?feature=oembed&#038;enablejsapi=1\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/div>\n<\/p>\n<\/figure>\n<p class=\"wp-block-paragraph\">The company says that both Fable 5 and Mythos 5 cost less than half the price of the Claude Mythos Preview at $10 per million input tokens and $50 per million output tokens. <\/p>\n<p class=\"wp-block-paragraph\">The new, more expensive models perform well compared to the Claude Opus 4.8 and GPT-5.5, according to Anthropic results. <\/p>\n<figure class=\"wp-block-image alignwide size-large\"><img loading=\"lazy\" decoding=\"async\" height=\"576\" width=\"1024\" src=\"https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?w=1024\" alt=\"\" class=\"wp-image-1055858\" srcset=\"https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp 3840w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=155,87 155w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=655,368 655w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=768,432 768w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=1024,576 1024w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=1536,864 1536w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=2048,1152 2048w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=350,197 350w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=140,79 140w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=1600,900 1600w, https:\/\/9to5mac.com\/wp-content\/uploads\/sites\/6\/2026\/06\/036229d8f9be9a5a911dbbd863b3c6cc09a79a70-3840x2160-1.webp?resize=150,84 150w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\"\/><\/figure>\n<p class=\"wp-block-paragraph\">Anthropic says the two new models &#8220;can operate independently longer than any previous Claude models.&#8221; This improves Claude&#8217;s use in software engineering, information work, vision, and memory and long-term content. <\/p>\n<figure class=\"wp-block-embed alignwide is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<p><div class=\"youtube-embed\" data-video_id=\"CIQBP1w4B1M\"><iframe loading=\"lazy\" title=\"Claude Fable 5 beats Pok\u00e9mon FireRed only using vision\" width=\"696\" height=\"392\" src=\"https:\/\/www.youtube.com\/embed\/CIQBP1w4B1M?feature=oembed&#038;enablejsapi=1\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/div>\n<\/p>\n<\/figure>\n<p class=\"wp-block-paragraph\">Claude Fable 5 arrives for customers starting today. Anthropic says it expects demand for Fable 5 to be &#8220;very high, and difficult to predict.&#8221; For that reason, subscription plans will have access to Fable 5 in stages, according to Anthropic<\/p>\n<ul class=\"wp-block-list\">\n<li>From today until June 22, Fable 5 is included in the Pro, Max, Team, and Enterprise plans based on the chair at no additional cost.<\/li>\n<li>On June 23rd, we will remove Fable 5 from those plans. Using it after that will require usage credits. If the capacity is acceptable, we will expand the installed window.<\/li>\n<li>After this point\u2014when sufficient volume allows us to do so\u2014we intend to reinstate Legend 5 as a regular part of subscription plans. We aim to do this as soon as possible.<\/li>\n<\/ul>\n<p class=\"wp-block-paragraph\">You can read more about Anthropic&#8217;s new Claude Fable 5 model here.<\/p>\n<p class=\"wp-block-paragraph\"><strong>News about Anthropic:<\/strong><\/p>\n<div class=\"google-preferred-source-badge\">\n<p>\t\t\t<img decoding=\"async\" class=\"google-preferred-source-badge-dark\" src=\"https:\/\/9to5mac.com\/wp-content\/themes\/ninetofive\/dist\/images\/google-preferred-source-badge-dark.png\" alt=\"Add 9to5Mac as a favorite source on Google\"\/><br \/>\n\t\t\t<img decoding=\"async\" class=\"google-preferred-source-badge-light\" src=\"https:\/\/9to5mac.com\/wp-content\/themes\/ninetofive\/dist\/images\/google-preferred-source-badge-light.png\" alt=\"Add 9to5Mac as a favorite source on Google\"\/><\/p><\/div>\n<div class=\"ad-disclaimer-container\">\n<p class=\"disclaimer-affiliate\"><em>FTC: We use auto affiliate links to earn income.<\/em> More.<\/p>\n<p><!-- post ad --><\/div>\n<\/p><\/div>\n\n","protected":false},"excerpt":{"rendered":"<p>Back in April, Anthropic unveiled its Claude Mythos AI model that it says is too powerful to be released publicly. Instead, the company shared access with software vendors, including Apple, in an effort to use the model to improve online security. Now, as promised, Anthropic has released what it calls a Mythos-class model that customers [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":14856,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":{"0":"post-14855","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-smartphones-tablets"},"_links":{"self":[{"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/posts\/14855","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/comments?post=14855"}],"version-history":[{"count":1,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/posts\/14855\/revisions"}],"predecessor-version":[{"id":14857,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/posts\/14855\/revisions\/14857"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/media\/14856"}],"wp:attachment":[{"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/media?parent=14855"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/categories?post=14855"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.runwayritz.com\/index.php\/wp-json\/wp\/v2\/tags?post=14855"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}