Claude Mythos is different.
Claude Fable 5 and Mythos 5: The System Card
First things first: Claude Fable 5 is the new best publicly available model.
Claude Fable 5 and Claude Mythos 5
Today we’re launching Claude Fable 5: a Mythos-class model that we’ve made safe for general use.
How good is Mythos?
Is Claude Mythos Preview a particularly big jump in AI capabilities?
Anthropic releases Claude Fable, a version of Mythos, days after warning AI is becoming too dangerous
Anthropic is releasing Claude Fable 5, its first Mythos-class model available to the public. The model comes with guardrails that block responses in high-risk areas like cybersecurity and biology.
Claude Mythos #2: Cybersecurity and Project Glasswing
Anthropic is not going to release its new most capable model, Claude Mythos, to the public any time soon.
Claude Opus 5 Is Highly Capable, But Is No Mythos
Claude Opus 5 is a weirder than usual release to evaluate, for two reasons.
Claude Mythos #3: Capabilities and Additions
To round out coverage of Mythos, today covers capabilities other than cyber, and anything else additional not covered by the first two posts, including new reactions and details.
Claude Opus 5: The System Card
Claude Opus 5 is trying to be the best of both worlds.
Claude Mythos Preview \ red.anthropic.com
Earlier today we announced Claude Mythos Preview, a new general-purpose language model. This model performs strongly across the board, but it is strikingly capable at computer security tasks. In response, we have launched Project Glasswing, an effort to use Mythos Preview to help secure the world’s most critical software, and to prepare the industry for the practices we all will need to adopt to keep ahead of cyberattackers.
Introducing Claude Fable 5.1 and Claude Mythos 5.1
Our most advanced models for coding and knowledge work. Their research capabilities also offer an early glimpse of how AI models will contribute to scientific progress.
Claude Mythos Preview: Anthropic's Cybersecurity AI
Guide to Claude Mythos Preview, Anthropic's most capable AI model. Capabilities, benchmarks, Project Glasswing, cybersecurity impact, and business implications.
Is Anthropic's Claude Mythos A Big Stunt, Or A Real Security Threat? What The Experts Say
The federal government summoned financial leaders to an emergency meeting over Claude Mythos last week.
Three Labs With a Plan and A Memorandum
The big story today is the release of Claude Fable 5, the version of Claude Mythos that Anthropic believes they can safely distribute to the people.
A field guide to Claude Fable 5: Finding your unknowns | Claude | Claude by Anthropic
Practical patterns for agentic coding with Claude Fable: how to find your unknowns before, during, and after implementation, from the team at Anthropic.
Claude Fable 5 and Mythos 5: Capabilities
Only three days after the release of Claude Fable 5, Anthropic was forced by the United States Government to make it unavailable, when a jailbreak was brought to its attention, rather than the previous situation of ‘yes obviously experts can jailbreak anything if they care enough’ and ‘yes obviously you can ask Fable to fix your code.’
