Is your RAG manpages thing on github somewhere? I was thinking about doing something like that (it's high on my to-do list but I haven't actually done anything with llms yet.)
$ man --html="$(which markitdown)" <man page>
My tool can read stdin, send it to an LLM, and do a couple nice things with the reply. Not exactly RAG, but most man pages fit into the context window so it's okay.