Google finally said it: llms.txt does nothing for Search. Here is what actually reads it.

By the DenverSEO.io team · 2026-10-19

What Google said, in the record

Two official statements settle it. The Search Central changelog entry dated June 15, 2026 notes that Google Search does not use llms.txt. And the AI optimization guide, updated July 10, 2026, says sites do not need to create “new machine readable files, AI text files, markup, or Markdown” to appear in AI features; a page has to be indexed and eligible for a normal snippet.

Chrome’s own Lighthouse documentation, from the team that shipped the Agentic Browsing audit, calls llms.txt an “emerging convention” and audits only whether the file returns a server error. A missing file is marked not applicable. That is the strongest endorsement it has from any Google property: please do not 500.

What the logs say

Ahrefs looked at request logs across 137,210 domains for May 2026. The findings, in their words and numbers:

• 28% of the domains publish an llms.txt.
• 97% of those files received zero requests during the month.
• 96% of the requests that did arrive came from bots, not humans or assistants answering a question.
• 1.1% of requests came from AI retrieval crawlers, the ones that feed live answers.
• The second most active fetcher was Claude-Code, a developer tool reading the file while someone programs, which is a very different use from a customer asking for a plumber.

So the file is being read, a little, by software that is building things, and almost never by the systems that decide whether your business is recommended. That matches what we see in our own logs: a handful of fetches a month, most from developer agents and scrapers.

Why it was oversold

Because it is easy. Writing a Markdown summary of your site takes an afternoon and produces a visible deliverable. Fixing JavaScript rendering, naming every button, cleaning a structured-data graph and rewriting service pages to open with the answer takes weeks and produces nothing you can screenshot. Agencies sold the afternoon. John Mueller’s comparison of llms.txt to the old meta keywords tag, reported secondhand, is the right frame: a self-declared signal that costs nothing to fake, which is exactly why retrieval systems do not lean on it.

Keep it, for the right reasons

We publish llms.txt and llms-full.txt on this site and we are not taking them down. Three honest reasons:

1. They cost nothing and cannot hurt, provided they do not contradict the site.
2. Developer agents do read them. If a developer is using an AI tool to evaluate vendors or integrate with you, the file is a courtesy.
3. Writing one forces you to state what the site is for in plain language, which is a useful exercise even if nobody else reads the result.

Two cautions. Keep it consistent with the HTML; a file that claims services the site does not describe reads as noise. And never put instructions in it. A file that tells a model what to say about you is, since Google’s May 2026 spam policy update, an attempt to manipulate generative AI responses, and it is also a prompt-injection surface on your own domain.

What to do instead

The same five things we put in every LLM SEO engagement, each verifiable in View Source:

1. Serve the answer in the initial HTML. Several AI crawlers do not run JavaScript. Our note on what AI crawlers actually read has the per-crawler details.
2. Let the right crawlers in. OAI-SearchBot, PerplexityBot, ClaudeBot and Googlebot. Check with the AI crawler checker.
3. Make every service page a quotable passage. Question-shaped heading, answer in the first two sentences, a number and a date.
4. One set of business facts, everywhere. Site, schema, Google Business Profile, directories.
5. Measure with a transcript, not a score. Twenty real questions, six engines, monthly.

Then score the page with the machine-readability analyzer. It reads the HTML the way a retriever does, which is the test llms.txt was pretending to pass.