
Claude Fable 5 Review: Mythos Power, Real Guardrails
Claude Fable 5 delivers the strongest coding and long-context results Anthropic has ever shipped publicly, but its safety classifiers block enough legitimate work to make that power conditional.
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Claude Fable 5 delivers the strongest coding and long-context results Anthropic has ever shipped publicly, but its safety classifiers block enough legitimate work to make that power conditional.

Claude Fable 5 is Anthropic's first publicly available Mythos-class model, with safety classifiers that fall back to Claude Opus 4.8 for high-risk requests across cybersecurity, biology, and chemistry.

Anthropic opens Mythos-class capabilities to the public with Claude Fable 5 at $10/$50 per million tokens, days after calling for a global AI pause.

PM Mark Carney's AI for All commits $2.3 billion to hit 250,000 new jobs and 60% business adoption by 2034 - but critics call it a wish list without hard delivery mechanisms.

Three papers: strategic attack timing exposes gaps in AI control evaluations, Perplexity's agents slash task time by 87%, and Lean4 formal proofs make agent workflows more reliable.

Anthropic published internal data showing Claude writes 80% of its own codebase - and called for a coordinated global AI pause - four days after filing a $965B IPO.

OpenAI's new Lockdown Mode cuts the network exits that prompt injection attacks use to steal data from ChatGPT - but won't stop malicious instructions from entering the model in the first place.

Three new arXiv papers expose how developers miss AI sabotage 94% of the time, why LLMs converge structurally in code evolution, and how ZK proofs could verify frontier AI training.

A bipartisan Congressional bill would freeze state AI laws for three years and require frontier developers to publish catastrophic risk plans, submit to federal audits, and face $1M daily fines.

Florida becomes the first US state to hold an AI CEO personally liable, filing an 83-page complaint accusing OpenAI and Sam Altman of hiding ChatGPT's dangers while racing for market share.

Three new papers tackle how routine AI use quietly rewires emotional habits, how to spend compute where failures cost most, and why agentic RAG errors compound before anyone notices.

Anthropic analyzed 832 banned accounts over 12 months and found AI-assisted threat actors grew from a third to more than half of all high-risk cases.