"In SWE-bench Pro for example, Claude Mythos beats out Opus 4.6 by 25%."

"Claude Mythos getting 83% beats out Gemini 3.1 Pro 82% and GPT 5.4 Pro at 80%. But on the subset remix, Claude Mythos gets the same score as Gemini 3.1 Pro and slightly underperforms GPT 5.4 Pro, which gets 88%."

"The geometric mean productivity uplift according to technical staff surveyed within Anthropic was 4x, four times the productivity when using Mythos."

"Humanity's Last Exam designed to test topics so obscure that it would indeed be the last exam that AI would saturate. Well, when allowed some tools, Claude Mythos gets almost two-thirds of those questions right compared to around 50% for other Frontier models."