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Part of Generative Engine Optimization

llms.txt

A plain-text Markdown file at /llms.txt that lists the highest-signal URLs on your site for LLM crawlers.

Overview

llms.txt is a community standard (originally proposed by Jeremy Howard) for a Markdown file at the root of a domain. It functions like a curator's note for LLMs: instead of crawling everything, models can read llms.txt and prioritize the canonical pages — docs, key landing pages, changelogs, glossaries. Pair it with llms-full.txt for long-form context that fits inside a single LLM ingestion.

Components

Key facts

  • llms.txt lives at the domain root, exactly like robots.txt.
  • It is Markdown, not XML — designed for LLMs to read directly.
  • Most sites publish a 30–80 line file; bigger isn't better.

How to apply llms.txt

  1. 1

    Review llms.txt generator

    Build the file. Check the current implementation, correct factual or technical gaps, then verify the public page rather than relying on configuration alone.

  2. 2

    Review Per-CMS guides

    WordPress, Shopify, Webflow setup. Check the current implementation, correct factual or technical gaps, then verify the public page rather than relying on configuration alone.

Implementation checks

CheckPass conditionEvidence to keep
AccuracyEvery claim matches the visible page and current source material.Source URL and review date
DeliveryImportant content is present in the public server response.Saved response or crawler test
ConsistencyNames, URLs, dates, and definitions agree across related pages.Template and entity audit
MeasurementA fixed test shows whether discovery or answer accuracy changed.Baseline and follow-up results

Common mistakes

  • Treating llms.txt as a one-time task instead of maintained site infrastructure.
  • Publishing claims or markup that visitors cannot verify on the page.
  • Changing several variables at once, then guessing which change affected visibility.
  • Measuring a single AI answer instead of a fixed panel of repeatable prompts.

Questions about llms.txt

What is llms.txt?
llms.txt is a community standard (originally proposed by Jeremy Howard) for a Markdown file at the root of a domain. It functions like a curator's note for LLMs: instead of crawling everything, models can read llms.txt and prioritize the canonical pages — docs, key landing pages, changelogs, glossaries. Pair it with llms-full.txt for long-form context that fits inside a single LLM ingestion.
Where should implementation start?
Start with llms.txt generator, verify the public result, then work through the remaining components in order. Record a baseline before making changes so the follow-up is meaningful.
How should success be measured?
Track technical validity, crawler access, accurate extraction, and citation presence across a fixed set of relevant questions. A single answer or crawler visit is not a trend.