llms.txt: what it does and does not do in 2026

Google said it plainly this year: llms.txt does not move Search, AI Overviews or AI Mode. Ordinary text. Done. I still saw people install a plugin that “optimises” the file for ranking the same week. That is time gone.

I still put the file up. Not for Google. For agents that want a short briefing before they tear through your HTML. ChatGPT, Perplexity, Claude: they want who you are and where the real pages live. A homepage full of sliders does not help them.

One paragraph. Three or four links that return 200. Prices if they do not change every week. Contact. I have seen 200-line “we are the leading…” files. An agent skips those, and should. Internal search URLs and UTM links do not belong either. That is clutter you will have to maintain.

It will not block training, replace robots.txt, or lift you into an AI Overview. Google cites HTML that answers a question, plus structured data. Not a reading guide in the root. If you want to block training, say so per bot in robots.txt. This file is not a lock.

After a migration, check the links. Dead URLs in llms.txt are worse than no file. Put it on the canonical host, HTTPS, no redirect chain. Keep the AI bots in robots.txt. That file is the yes or no. This one is only the map.