In this space I think I'm becoming LLM advocate.

Finding, reading outdated, writing, updating, grooming documentation is so much more expensive than just throwing LLM on repository (or multiple ones) with a "Go Fetch" quest.

Sure, it's ephemeral, but with assumptions of $50/h earn and assumption that non-naive piece of internal documentation takes 8h of work time and will be read ~100 times that comes in at $4 at read which I think is much more expensive than straight token-API costs (and probably much much more expensive than subsidized subscription costs).

And this is generous. Looking at Jira's stats from my past work, many long documents in small (but specialized) team were read 10-20 times boosting the (assumption-average-costs) to $20-$50 per read.

But wait, there's more (;-))! That's all assuming that knowledge absorption is 100%, what if only 50% of document is relevant. What if it's 25% etc.

In the end today there might as well be no documentation for code and LLMs could extract it raw from code. Raw - because I don't think indexers/RAGs/compressers are useful. I found that spending time on building such is fruitless: Indices can (and will) go stale just as materialized documents and lower context saturation results in more hallucinations in the end.

(There are out-of-code documents which obviously have no other source than then themselves so there's no other around it, though)