What are AI Crawlers?
AI crawlers are automated bots that AI companies use to fetch pages from the web. Some collect content to train language models. Others build the search indexes that AI assistants draw on when they answer, or fetch a single page because a user asked about it.
Each crawler identifies itself with a user agent. Common examples include GPTBot (OpenAI, training), OAI-SearchBot (ChatGPT search), ChatGPT-User (fetches triggered by ChatGPT users), ClaudeBot (Anthropic), PerplexityBot and Perplexity-User, CCBot (Common Crawl, whose open archive is widely used to train models), Bytespider (ByteDance) and Meta-ExternalAgent (Meta). Google works differently: it crawls with its existing crawlers and offers a separate robots.txt token, Google-Extended, to control use for Gemini.
Why AI crawlers matter for AI visibility
Crawling comes before citing. If the crawlers behind AI search features cannot reach or read your pages, assistants that look things up in real time have less of your own content to work with and lean more on what others say about you. Training crawlers, in turn, shape what future models know about your brand and category.
How your site is built matters too. Many AI crawlers read the raw HTML and do not execute JavaScript, so content that only appears after scripts run may be invisible to them. That makes server-side rendering a practical concern for AI visibility, not only a developer topic.
How to manage AI crawlers
Decide which bots you want: search crawlers help you appear in AI answers, training crawlers influence future models.
Set your rules per user agent in robots.txt, and check that your CDN, firewall or bot protection is not blocking the crawlers you want.
Serve important content, prices and structured data in the initial HTML.
Check your server logs to see which bots visit, which pages they request and which requests fail.
Verify that traffic claiming to be a known crawler really comes from that company, since user agents are easy to fake.
JavaScript-based analytics tools do not see bots, so this has to be measured on the server side. Trackbase's Crawler Analytics shows which AI crawlers visit your site and what they read.
Examples of AI Crawlers
A B2B payroll software vendor sees in its logs that OAI-SearchBot and PerplexityBot visit its pricing page every week, while its new comparison guides have not been crawled yet.
A Dutch bicycle webshop learns that its bot protection was blocking ClaudeBot and PerplexityBot, and adds an exception for the crawlers it wants.
A publisher blocks training crawlers such as GPTBot and CCBot but allows search crawlers, so its articles can still be cited in AI answers.
A SaaS company sees ChatGPT-User requests spike on one help article, a sign that users are asking ChatGPT about that exact topic.
Frequently asked questions
What is the difference between GPTBot and OAI-SearchBot?
Both belong to OpenAI but serve different purposes. GPTBot collects content that may be used to train OpenAI's models. OAI-SearchBot finds pages for ChatGPT's search features, and OpenAI says sites that block it will not be shown in ChatGPT search answers. You can allow one and block the other with separate rules in robots.txt.
Do AI crawlers execute JavaScript?
Many do not. They read the HTML your server returns and miss content that JavaScript adds later in the browser. Googlebot does render JavaScript, but you should not assume AI crawlers behave the same way. Put key content, product details and structured data in the initial HTML, for example with server-side rendering or static pages.
How can I see which AI crawlers visit my website?
Look at your server or CDN logs and filter on the user agents of known AI crawlers, such as GPTBot, OAI-SearchBot, ClaudeBot and PerplexityBot. Regular web analytics tools miss this traffic because bots do not run their tracking scripts. Crawler analytics tools, such as the one in Trackbase, show which bots visit and which pages they read.