I think a fundamental philosophical hurdle to consider here is: Who is the definitive authority of truth? “Facts” are a man-made concept used to describe or explain things as they are understood or believed by the source who is sharing the “fact”. All facts come from people, and all people are inherently biased, intentionally or not.
A great classic example is history. It is often said that history is written by the “winners”, meaning that history as we know it is merely a collection of notarized personal anecdotes and hearsay, from their points of view. But what about the “facts” that originated from the “losers” who never got the chance to memorialize them? Or got swept under the rug with the evidence destroyed?
Even science lol. Our understanding of scientific concepts is constantly changing. Once upon a time “the earth is flat” was an indisputable fact.
I realize this is kind of derailing the actual topic, but I think it’s something to consider early on in the process. A BS detector with no omniscience is not going to be a reliable tool. Thorough reviewing of sources can minimize some issues, but you will inevitably encounter “alternative facts” and contradictory/inconclusive information sneaking its way in.