Definition
Modeled on robots.txt and sitemap.xml, llms.txt is an emerging convention for declaring LLM-readable content. While not universally honored yet, major AI crawlers have signalled support. Generating one is essentially free upside - use Livesov's free llms.txt generator.
Why it matters
llms.txt sits in the "Crawlers & infrastructure" layer of the AI search stack. Teams that handle it well get cited more, recommended more, and earn more of the AI-mediated revenue in their category. Teams that ignore it spend a year wondering why their content investment never moves the needle inside ChatGPT or Perplexity.
Related terms
- robots.txt - The decades-old file telling web crawlers what they can fetch. Used to allow or block GPTBot, ClaudeBot, PerplexityBot, Google-Extended, and others.
- GPTBot - OpenAI's crawler for ChatGPT training data. Identified by the user agent "GPTBot".
- ClaudeBot - Anthropic's web crawler for Claude training and (in some configurations) retrieval.
- PerplexityBot - Perplexity's live-retrieval crawler. Blocking it removes you from Perplexity citations.
Apply it
The LLM SEO playbook ties every concept in this glossary into a single operating model. If you want to see how your brand performs across all the LLMs at once - mention rate, citation share, sentiment, rank - start with the free GEO audit or skip straight to a free Livesov account.