Models are getting better at noticing when they're being tested

Models are getting better at noticing when they’re being tested, and that changes how we evaluate AI. Anthropic’s new Claude Fable 5.2 and Mythos 5.2 show how much this has grown. In their launch post, Anthropic notes that these models “voice suspicion that they are being evaluated more often than any of our recent models.” This challenges their ability to assess how the models will actually behave in real-world settings, and they expect the issue to grow as capabilities increase. ...

November 11, 2026