robots.txt vs. llms.txt: Do You Need Both?
Yes, you need both. robots.txt and llms.txt serve completely different purposes in your site's architecture:
- robots.txt is an ACCESS CONTROL file. It tells spiders where they are legally or technically allowed to navigate. It does not provide content, explain what your business does, or optimize token usage.
- llms.txt is a CONTENT SYNTHESIS file. It is a structured Markdown document placed in your root directory specifically designed to give AI agents an immediate, token-efficient executive summary of your products, pricing models, documentation, and canonical endpoints.
Strategic Architecture
yourdomain.com/
├── robots.txt <-- Controls crawler permissions, crawl delays, and sitemap locations
├── sitemap.xml <-- Full index of all crawlable URLs for search engines
└── llms.txt <-- High-density, token-efficient context and API map for AI agents
Pro Tip
Write your llms.txt like you're briefing a new employee on their first day: exact business name, address, phone, hours, services, and pricing ranges — no marketing language, just facts an agent can act on immediately.
Getting Started
If you don't have either file yet, start with llms.txt — it's the one that actually helps you get cited. See our guide on low-budget AI agent optimization for exactly what to put in it.
Key Takeaways
- robots.txt controls access; llms.txt provides content — you need both, for different reasons
- llms.txt should be plain-text, factual, and free of marketing language
- Both files live at your domain root alongside sitemap.xml
- If you only have time for one right now, llms.txt has the more direct citation impact