I usually assume that my audience has approximately all the context that I have. I'll structure things like lists of links or otherwise not explain relevant background. I think having a take on the background is often the most interesting thing, though! Approximately nobody has read exactly what I've read, or thinks in exactly the way I do, so it makes little sense to only keep the most absolutely original thoughts and not explain the rest. Literature review, for instance, is an extremely valuable service, but one that is mostly helpful insofar as one explains and compresses the literature!