Often when LLMs give me some command option or advice I haven’t seen before I try to independently verify it. And I’ve often been frustrated just how hard it is to find this info from the source documents.

Though a lot of the time this is more an inefficiency of the documentation and Google rather than something only LLMs could do.

As the rate of 'hallucinations' seems to have dropped dramatically (at least IME as regards non-existent flags and the like), I'm more concerned with usage. I often use grep.app/GH code search to look for usage examples as a sanity check when things look "off", for exactly the reason you described--there's often a total lack of good documentation on things like that, especially on "younger" tools/stuff.