In this context, it would mean building a knowledge base the model can link to that is considered authoritative. So maybe the LLM is has some slop in it's training, and that causes it to try and output some junk, but if it can't match it to it's verified ground-truth KB it doesn't end up outputting it.

The problem is figuring out what is the authoritative sources.

But we're talking about AI writing and/or influencing other people's online discourse, not?