GPTBot vs OAI-SearchBot: Which AI Crawlers Should Your robots.txt Allow?

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Someone recently told me, “I blocked every bot with AI in its name. Why is my site missing from ChatGPT and Perplexity?”

That is the problem with treating every crawler as the same.

GPTBot, OAI-SearchBot, Google-Extended, PerplexityBot, ChatGPT-User, and Perplexity-User have different jobs. Blocking all of them in one sweep can remove your website from AI search citations while doing nothing to protect private files or insecure code.

Use robots.txt to control crawl preferences. Do not use it as your only security layer.

The short answer

If you want visibility in answer engine optimization and AI search optimization:

✅ Allow OAI-SearchBot so ChatGPT can discover and cite your pages.

✅ Allow PerplexityBot so Perplexity can index and cite your pages.

✅ Allow Googlebot so your pages remain available in traditional Google Search.

✅ Decide separately whether to allow GPTBot and Google-Extended for training and model-use purposes.

✅ Treat ChatGPT-User and Perplexity-User as user-triggered fetchers, not regular indexing crawlers.

❌ Do not write one broad rule that blocks every bot containing “AI” or “GPT”.

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GPTBot and OAI-SearchBot are not the same

OpenAI documents these crawlers separately. Their settings are independent.

Bot name	Primary purpose	Recommended action
GPTBot	Crawls public content that may be used to train OpenAI foundation models	Allow only if you accept this use. Disallow if you want to opt out of training
OAI-SearchBot	Helps power ChatGPT Search results and website citations	Allow if you want to appear in ChatGPT search answers
ChatGPT-User	Fetches a page after a specific user request in ChatGPT, Custom GPTs, or GPT Actions	Usually allow if you want user-requested pages to load. robots.txt may not reliably control it
Googlebot	Crawls pages for Google Search and related search features	Allow if you want Google visibility
Google-Extended	Controls use of Google-crawled content for Gemini model training and grounding	Decide separately from Googlebot. Blocking it does not remove your site from Google Search
PerplexityBot	Crawls and indexes pages for Perplexity search and citations	Allow if you want Perplexity visibility
Perplexity-User	Fetches a page after a specific Perplexity user request	A robots.txt rule is mainly a policy signal. Use a WAF or CDN rule for stronger control

OpenAI’s official crawler documentation confirms that blocking GPTBot does not automatically block ChatGPT Search. ChatGPT Search is controlled by OAI-SearchBot.

Google also explains that Google-Extended does not affect inclusion in Google Search. It controls how Google may use crawled content for Gemini-related training and grounding.

Perplexity documents PerplexityBot and Perplexity-User as separate agents. PerplexityBot supports automated search indexing. Perplexity-User is triggered by an individual request.

What blocking each crawler actually costs

Block GPTBot

You signal that your public content should not be used to train OpenAI foundation models.

You do not automatically disappear from ChatGPT Search if OAI-SearchBot remains allowed.

✅ Useful configuration:

• Allow OAI-SearchBot
• Disallow GPTBot

This keeps a path open for ChatGPT search citations while separating that decision from training access.

Block OAI-SearchBot

You remove your pages from ChatGPT Search answers, according to OpenAI’s documentation.

Your pages may still appear as navigational links when a user searches for your brand or URL, but they are less likely to be retrieved as cited sources for broader questions.

❌ Blocking OAI-SearchBot because you do not want GPTBot training access is the wrong fix.

Block Googlebot

You restrict Google Search crawling.

For most founders, this is an expensive mistake. It can reduce discovery, indexing, organic traffic, and the traditional SEO foundation that also supports answer engine optimization.

Block Google-Extended

You signal that Google should not use eligible crawled content for certain Gemini training and grounding uses.

This does not remove your pages from the standard Google index.

Block PerplexityBot

You reduce the chance that Perplexity will crawl, index, and cite your pages.

Perplexity may still retain limited domain, headline, or summary information in some situations. If you want stronger control over user-triggered access, robots.txt alone is not enough.

Block ChatGPT-User or Perplexity-User

These rules do not work like normal automated crawler rules.

Both agents can be triggered by a person asking a question or requesting a specific page. The request resembles a browser visit. Network controls, authentication, application logic, and WAF rules are more appropriate if you need to restrict this access.

A practical robots.txt example

If your goal is traditional search visibility and answer engine citations, while opting out of the two better-known training controls, your file could look like this:

User-agent: Googlebot
Allow: /

User-agent: OAI-SearchBot
Allow: /

User-agent: PerplexityBot
Allow: /

User-agent: ChatGPT-User
Allow: /

User-agent: Perplexity-User
Allow: /

User-agent: GPTBot
Disallow: /

User-agent: Google-Extended
Disallow: /

This is an example, not a universal policy.

Review your content licensing, contracts, privacy requirements, and business model before choosing a rule. Also check your CDN or WAF. A crawler can identify itself with a user-agent string, but user-agent strings should not be treated as perfect identity verification.

Use the Robots.txt Generator to create a clean starting file. It is free, requires no login, and has no email gate or paywall.

The five-step AI crawler playbook

1. Create or open your robots.txt file

Visit:

https://yourdomain.com/robots.txt

If it returns a 404, create the file in your website root.

For a fast setup, use the free Robots.txt Generator. Copy the result and upload it next to your sitemap and homepage configuration.

Check for dangerous rules such as:

User-agent: *
Disallow: /

That single rule can block your entire site from ordinary crawlers if no more specific configuration overrides it.

2. Allow the retrieval and user-triggered agents you want citing you

For visibility, review these agents individually:

• OAI-SearchBot
• PerplexityBot
• ChatGPT-User
• Perplexity-User
• Googlebot

Do not assume that allowing GPTBot is required for ChatGPT citations. It is not the search-specific OpenAI crawler.

✅ Make independent decisions.

❌ Do not group every crawler into “allowed” or “blocked” based only on its name.

3. Add an llms.txt file

Create:

https://yourdomain.com/llms.txt

An llms.txt file can identify your business, explain your site, and point crawlers toward the pages that matter most.

Include:

• Your company name
• A one-line description
• Your homepage
• Your strongest service pages
• Helpful guides
• Pricing or product information
• Contact or documentation pages

Use the free llms.txt Generator. Save the output at your website root, next to robots.txt.

An llms.txt file does not replace crawl permissions. It helps clarify your site after a crawler can reach it.

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4. Verify that every file is reachable

Open these URLs in a private browser window:

https://yourdomain.com/robots.txt
https://yourdomain.com/llms.txt
https://yourdomain.com/sitemap.xml

Confirm that:

• Each file returns a successful response
• The files are not blocked by authentication
• The files use the correct domain and protocol
• Your sitemap contains the important pages
• Your important pages do not contain accidental noindex directives
• Your canonical URLs point to the correct versions
• Your server does not return an error to crawlers

A file that exists locally but cannot be reached publicly does not help search engines or answer engines.

5. Re-run a free SEO/AEO audit

Run a free SEO/AEO audit after updating the files.

The audit checks whether your pages have the structural signals that support traditional SEO and answer engine optimization, including:

• Crawlability
• Answer structure
• Entity clarity
• Citation worthiness
• Semantic completeness
• Structured data
• Meta tags
• Indexable pages

Every feature is free. There is no login, email requirement, paywall, or limited preview.

If the audit identifies missing page titles or descriptions, use the Meta Tag Generator.

If structured data is missing, use the Schema Markup Generator to create JSON-LD for your organization, articles, products, FAQs, or local business.

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SEO, AEO, and security are connected

Opening your site to useful crawlers can improve discovery and citations. It can also make you look more closely at what your website exposes.

robots.txt is public. Anyone can read it.

Do not place passwords, API keys, private URLs, or confidential notes in the file. Do not assume that writing:

Disallow: /admin/

actually protects /admin/.

It only tells compliant crawlers not to request that path. It does not create authentication, encryption, or access control.

❌ Hide a secret file with robots.txt.

✅ Remove the secret, restrict access at the server level, rotate exposed credentials, and scan for public configuration files.

Use the Vulnerability Check through the free SEO audit to look for publicly visible security issues such as missing protection headers, exposed files, leaked credentials in page source, outdated libraries, and weak cookie settings.

This is especially important for solo founders and vibe-coders. Fast website builders can produce a working launch before anyone checks the generated code, headers, dependencies, or public file paths.

Use the Free Tools page to keep the basic workflow in one place:

• Meta Tag Generator
• Schema Markup Generator
• Robots.txt Generator
• llms.txt Generator
• Search Console Regex Library
• Free SEO/AEO analyzer
• Vulnerability Check

Final checklist

Before you publish your next AI-built website, confirm:

✅ Googlebot can reach your public pages.

✅ OAI-SearchBot is allowed if you want ChatGPT citations.

✅ PerplexityBot is allowed if you want Perplexity citations.

✅ GPTBot reflects your training preference.

✅ Google-Extended reflects your Gemini training and grounding preference.

✅ User-triggered fetchers are handled with realistic expectations.

✅ robots.txt and llms.txt are reachable at the root.

✅ Your sitemap lists the pages you want discovered.

✅ Your SEO and AEO audit shows no critical crawl blocks.

✅ Your security scan checks what your public files and code reveal.

The goal is not to allow every crawler blindly. The goal is to make deliberate choices.

Keep the three pillars together: SEO for traditional discovery, AEO for answer engine citations, and website security for safe access.

All Smart Analytics tools are completely free, with no signup, no email requirement, and no paywall. Run the free SEO/AEO audit, check your crawler rules, and scan your site for exposed security issues before your next launch.

Sources

• OpenAI Crawlers
• Google Common Crawlers and Google-Extended
• Perplexity Crawler Documentation