Was this a GPT model? OpenAI seems to have developed an almost-acknowledged inability to usefully pre-train a model after mid-2024. The recent GPT versions are impassively lacking in newer knowledge.

The most amusing example I’ve seen was asking the web version of GPT-5.1 to help with an installation issue with the Codex CLI (I’m not an npm user so I’m unfamiliar with the intricacies of npm install, and Codex isn’t really an npm package, so the whole use of npm is rather odd). GPT-5.1 cheerfully told me that OpenAI had discontinued Codex and hallucinated a different, nonexistent program that I must have meant.

(All that being said, Gemini is very, very prone to hallucinating features in Google products. Sometimes I wonder whether Google should make a list of Gemini-hallucinated Google features and use the list to drive future product development.)