Big fan of reader mode. For me, a direction better than llms.txt would be to encourage sites to improve their markup (think semantic web era) so agents could get the text version from that the way reader mode does. Would achieve the same thing - save tokens.

This isn't difficult and I think the reason it hasn't been done is that publishers want clicks and ad views. Which begs the question: why would they start doing it for agents?

I know about reader mode but rarely use it. Perhaps I feel like any web site that needs it doesn't have anything worth reading.