How AI Crawlers Index Your Website (And What You Can Do About It)
GPTBot, PerplexityBot, Google-Extended — AI crawlers work differently from traditional search bots. Understanding how they index content is the foundation of all technical AEO work.
There are now more AI crawlers indexing the web than there are traditional search bots. Each one has different crawl behavior, different content priorities, and different robots.txt conventions. Getting technical AEO right starts with understanding exactly who is crawling your site and how. Verify your bot access status with a single scan.
The Major AI Crawlers and What They Power
| Crawler User Agent | Powers | Respects robots.txt | Crawl Frequency |
|---|---|---|---|
GPTBot | ChatGPT web browsing, SearchGPT | Yes | Periodic |
OAI-SearchBot | OpenAI search indexing | Yes | Frequent |
PerplexityBot | Perplexity AI all products | Yes | Frequent |
Google-Extended | Gemini, AI Overviews | Yes | High frequency |
ClaudeBot | Claude web search | Yes | Periodic |
Bytespider | ByteDance AI products | Yes (inconsistently) | High frequency |
Applebot-Extended | Apple AI features | Yes | Periodic |
cohere-ai | Cohere enterprise AI | Yes | Periodic |
How AI Crawlers Differ From Googlebot
Traditional SEO teaches you to optimize for Googlebot. AI crawlers have meaningfully different behavior:
Content Extraction vs. Index Ranking
Googlebot crawls to build a ranked index — it evaluates thousands of signals to determine where your page ranks. AI crawlers crawl to extract content for RAG (Retrieval-Augmented Generation) databases. They are not ranking your page; they are deciding whether to store it as a trustworthy source.
This changes what matters:
- →Googlebot: Prioritizes backlinks, PageRank, Core Web Vitals
- →AI crawlers: Prioritize content structure, schema signals, author credibility, factual density
JavaScript Rendering
Most AI crawlers do not render JavaScript. If your key content is loaded via JavaScript (React, Vue, Angular with client-side rendering), it may be invisible to AI bots even if Googlebot can see it.
Fix: Ensure content-critical pages use server-side rendering (SSR) or static generation. For Next.js apps, verify key pages use getServerSideProps or are statically generated.
Crawl Rate and Politeness
AI crawlers generally respect Crawl-delay directives and are more conservative with crawl rate than Googlebot. However, some (particularly Bytespider) have been reported ignoring crawl delays. Configure server-side rate limiting if you see aggressive crawl behavior.
Robots.txt Configuration for AI Crawlers
The most common technical AEO mistake: accidentally blocking AI crawlers.
The Safe Configuration
User-agent: GPTBot
Allow: /
User-agent: OAI-SearchBot
Allow: /
User-agent: PerplexityBot
Allow: /
User-agent: Google-Extended
Allow: /
User-agent: ClaudeBot
Allow: /
User-agent: Bytespider
Allow: /
If you want to block certain paths from AI crawlers (e.g., private user dashboards) while allowing the public site:
User-agent: GPTBot
Disallow: /dashboard/
Disallow: /api/
Allow: /
Checking Your Current Configuration
- →Visit
yoursite.com/robots.txt - →Look for
Disallow: /entries under any AI user agent - →Check for catch-all
User-agent: *rules with broadDisallowdirectives
Many sites have legacy catch-all rules that were written before AI crawlers existed. A rule like Disallow: / under User-agent: * blocks all AI crawlers unless individual Allow overrides exist.
The llms.txt Convention
A new convention is emerging: the [llms.txt](/blog/complete-guide-llms-txt-new-robots-txt-ai-crawlers) file. Similar to sitemap.xml, it is a plain-text file at yoursite.com/llms.txt that provides AI models with a curated list of your most important content.
While not yet a formal standard, early evidence suggests AI systems that support it use it to prioritize crawl resources. A basic [llms](/blog/entity-authority-vs-domain-authority).txt looks like:
# Company Name
> One-line description of your company and what you do
## Core Content
- [Page Title](https://yoursite.com/page): Brief description
- [Another Page](https://yoursite.com/another): Brief description
## Products
- [Product Name](https://yoursite.com/product): Product description
This is particularly valuable for directing AI bots to your most authoritative content rather than having them crawl pages you would not want cited (e.g., old blog posts, thin category pages).
Monitoring Crawl Activity
To verify AI bots are actually accessing your site:
- →
Server logs: Filter for known AI user agent strings. Access logs will show you crawl frequency and which pages are being visited.
- →
RankAsAnswer bot verification: Run a bot access audit to see which AI crawlers have successfully indexed your key pages.
- →
Google Search Console: Monitor crawl stats under "Settings → Crawl stats" for Google-Extended specifically.
Fix any access issues before investing in content optimization. A blocked bot cannot cite you regardless of how good your content is.
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