New: free AI Visibility Check — see where ChatGPT, Gemini & AI Overviews mention your brand. Get yours →
Technical

AI Crawlers, robots.txt and llms.txt: A Plain-English Setup Guide

Ravi Fuleriya 2 min read Updated 21 Oct 2026
Two strategists planning at a whiteboard

Photo: Paymo / Unsplash

Key takeaways

  • Separate search bots (which affect whether you are cited) from training bots (which affect model training).
  • Blocking Google-Extended does not remove you from Google Search or AI Overviews.
  • llms.txt is a low-cost addition, but no major engine has confirmed it affects citations.

Two kinds of AI bot

AI companies run different crawlers for different jobs. Search and retrieval bots fetch pages so an assistant can cite them in an answer. Training bots collect content to train future models. Many businesses want to allow the first and choose freely about the second.

The main crawlers

User agentCompanyPurpose
OAI-SearchBotOpenAIChatGPT search results
ChatGPT-UserOpenAIPages fetched when a user asks
GPTBotOpenAIModel training
PerplexityBotPerplexityPerplexity’s search index
Claude-SearchBot / Claude-UserAnthropicClaude search and user-requested fetches
ClaudeBotAnthropicModel training
GooglebotGoogleSearch, including AI Overviews and AI Mode
Google-ExtendedGoogleA control token for Gemini training and grounding; not a separate crawler
BingbotMicrosoftBing and Microsoft Copilot

Bot names change. Check each company’s documentation before you finalise your rules.

A sensible robots.txt

This example allows search and retrieval bots and blocks training bots. Remove the training blocks if you are happy for your content to be used in training.

# Allow AI search and user-requested fetches
User-agent: OAI-SearchBot
Allow: /

User-agent: ChatGPT-User
Allow: /

User-agent: PerplexityBot
Allow: /

User-agent: Claude-SearchBot
Allow: /

# Optional: opt out of model training
User-agent: GPTBot
Disallow: /

User-agent: ClaudeBot
Disallow: /

User-agent: Google-Extended
Disallow: /

Sitemap: https://www.example.in/sitemap.xml

Check for hidden blocks

  • CDN settings. Cloudflare and other providers now offer AI-bot blocking; check yours is not blocking search bots by default.
  • WordPress security and AI-bot plugins. Review their bot policies after every update.
  • Hosting firewalls. Some block unfamiliar user agents automatically.
  • JavaScript-only content. Not every AI crawler renders JavaScript; keep key text in the HTML.

What about llms.txt?

llms.txt is a proposed standard: a plain-text file at your site root that lists your most important pages for AI systems. It is quick to add and does no harm. But no major AI company has confirmed that it changes rankings or citations, so treat it as a tidy extra, not a strategy.

# AISEOAgency.in
> AI SEO agency in India offering GEO, AEO and technical SEO.

## Key pages
- [Services](https://aiseoagency.in/#services)
- [Pricing](https://aiseoagency.in/#pricing)
- [AI SEO in Bhopal](https://aiseoagency.in/ai-seo-agency-bhopal/)

Quick checklist

  1. List which bots you allow and block, and why.
  2. Update robots.txt and test it with each search console.
  3. Check your CDN, firewall and plugins.
  4. Make sure key content is in the HTML.
  5. Add llms.txt if you like.
  6. Recheck every quarter.
Want to know where you stand?Get a free AI visibility check across ChatGPT, Gemini and AI Overviews.
Get my free check →

Frequently asked questions

Will blocking GPTBot remove me from ChatGPT?

Not from ChatGPT search, which uses OAI-SearchBot. GPTBot is used for training. Allow OAI-SearchBot if you want to be cited.

Does blocking Google-Extended affect AI Overviews?

No. AI Overviews are part of Google Search, which uses Googlebot. Google-Extended controls use for Gemini model training and grounding.

Is llms.txt required?

No. It is optional, and its effect on AI citations is unproven.

RF
Ravi Fuleriya

Founder of InnovatorCraft and AISEOAgency.in. Performance marketer and former SEO team lead who has worked with 50+ businesses — now focused on how brands get found in ChatGPT, Gemini and AI Overviews.

Keep reading

Free AI Visibility Check

Does your brand show up when buyers ask AI?

Send us your website and three questions your customers ask. Within 3 working days, you get a short report showing where you appear today.

  • Your mention rate in ChatGPT, Gemini, Perplexity & AI Overviews
  • Which competitors AI recommends instead of you
  • The top 5 fixes we would make first

Get my free check

No spam. We reply within one working day. Want an instant score? Run the free checker →