fabricated citations

Ask a model to back up a claim with sources and it can produce something that looks impeccable: a plausible paper title, a realistic author list, a journal, a year, even a page range and a DOI. The only problem is that none of it exists. The model has seen millions of real citations and learned their format perfectly, so it generates the format flawlessly while the underlying reference is pure invention. Lawyers have been sanctioned for filing briefs built on such phantom cases.

The lesson is that a citation from an LLM is a formatting trick, not evidence. Looking right is the very thing the model is good at, and a fake reference is right where it is weakest — specific, verifiable, and rare in any exact form. Never trust a source the model names until you have found that source yourself. If grounding matters, give the model the documents and ask it to quote only from them.