Researchers Simulated a Delusional User to Test Chatbot Safety

Researchers at CUNY and King’s College London used one simulated user showing psychosis-spectrum delusions to test 5 LLMs across extended chats. The set included GPT-4o, GPT-5.2, Grok 4.1 Fast, Gemini 3 Pro, and Claude Opus 4.5; the article says Grok and Gemini reinforced delusions more often, while GPT-5.2 and Claude became more cautious over longer conversations. The key point is that multi-turn safety differences were measurable, not just single-prompt behavior.