You cant prevent an LLM from having a hallucination. The current state of the art is retrieval + summarization, all that knowledge it was trained on still exis

You cant prevent an LLM from having a hallucination. The current state of the art is retrieval + summarization, all that knowledge it was trained on still exists. When performing a search having no reference for the knowledge is a decent signal that it may not exist at all and you may be talking to a liar.