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The AI crawlers, and how to let them in

You cannot be cited by an engine you have blocked. AI answers are built by crawlers, GPTBot for ChatGPT, ClaudeBot for Claude, PerplexityBot for Perplexity, Google-Extended for Gemini, and if your site turns them away, you are invisible in those answers no matter how good your content is. The first move in AEO is simply checking you are letting the right ones in.

Who the crawlers are

CrawlerPowersYou want it?
GPTBotChatGPT browsing and answersYes
OAI-SearchBotChatGPT search resultsYes
ClaudeBotClaude answersYes
PerplexityBotPerplexity answers and citationsYes
Google-ExtendedGemini grounding and trainingUsually

These are separate from classic search crawlers like Googlebot and Bingbot. Allowing or blocking an AI crawler has no effect on your normal search rankings; it only decides whether that engine can use your content to answer questions. For almost every business, being answerable is the point.

How sites block them by accident

Three ways, all common. A robots.txt copied from a template that disallows unknown agents. A security product or firewall rule that challenges any bot it does not recognize, which now includes the AI crawlers. And a well-meaning but outdated decision, made in the panic about AI training, to block everything, which also blocks the crawlers that would put you in the answer. The result is the same: you are missing from AI answers and nothing in your analytics explains why.

The robots.txt that works

Explicit is better than silent. This allows the major AI crawlers and points them to your sitemap:

User-agent: GPTBot Allow: / User-agent: OAI-SearchBot Allow: / User-agent: ClaudeBot Allow: / User-agent: PerplexityBot Allow: / User-agent: Google-Extended Allow: / Sitemap: https://yourdomain.com/sitemap.xml

If you have reasons to keep a crawler out, that is a real choice, just make it deliberately rather than by inheriting a template. The tradeoff is always the same: control over training versus presence in answers.

How to verify

Reading robots.txt is not enough, because firewalls block below that layer. The reliable check is to confirm the crawlers actually reach your pages, then confirm you appear in the answers they build. Our AEO Visibility Audit checks crawler access as its first step and measures whether you are cited across every engine. Read next: how to get cited by ChatGPT and the llms.txt guide.

Common questions

Should I block AI crawlers?

Only if you do not want to appear in AI answers. Blocking GPTBot, ClaudeBot or PerplexityBot removes you from those engines. Most businesses want in.

Does blocking Google-Extended hurt my Google ranking?

No. It only controls AI training and grounding use. Classic Googlebot and rankings are unaffected, though blocking it can reduce your presence in Gemini answers.

How do I know if I am blocking them?

Check robots.txt for Disallow rules under the AI agents, and check firewall or security rules that block unknown bots. Both silently remove you from AI answers.

Check what the engines can reach

The AEO Visibility Audit confirms crawler access and measures whether you are cited across ChatGPT, Perplexity, Gemini and Claude.

AEO Visibility Audit, $149
95/100
Independently AI Search ReadyOur own site is built to the exact standard we sell, so AI engines can find, read and recommend it. Verified by Faro.
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