Why does AI crawler indexability matter?

If your site blocks GPTBot, PerplexityBot, or ClaudeBot in robots.txt, those engines cannot fetch your pages and cannot cite you in AI answers. Google-Extended controls whether Google can use your content to train Gemini and generate AI Overviews. Blocking these bots is a common, invisible cause of zero AI visibility.

What's the difference between robots.txt and a live block?

robots.txt is a polite request; well-behaved bots respect it. A live block (403, 401, 429, or a Cloudflare / WAF challenge) rejects the bot at the network layer regardless of robots.txt. This tool checks both: the robots rule for each user agent and the live HTTP response when we identify as that bot.

Should I allow all AI crawlers?

For most brands that want AI visibility, yes. The exception is training-only crawlers (GPTBot, ClaudeBot, Google-Extended, CCBot) if you have a strategic reason to withhold your content from LLM training while still being cited live. Live-fetch bots (ChatGPT-User, Perplexity-User, Claude-Web, OAI-SearchBot) are the ones that produce citations, so those should almost always be allowed.

The tool shows 'blocked' but I never added a rule. Why?

Common causes: (1) a Cloudflare 'Block AI Scrapers' rule set at the edge, (2) a WAF challenge that returns 403 to unknown user agents, (3) a Vercel / Netlify header rule, or (4) a security plugin on WordPress. Check your CDN or firewall before editing robots.txt.

Free tool

Is Your Site Blocking ChatGPT, Perplexity & Claude?

Free AI crawler access test for any website. We fetch your robots.txt and request your homepage as thirteen major AI bots. GPTBot, ChatGPT-User, OAI-SearchBot, PerplexityBot, ClaudeBot, Claude-Web, Google-Extended, Applebot-Extended, Bytespider, CCBot, Meta-ExternalAgent, Amazonbot, and cohere-ai, then show you exactly which engines are allowed to read, index, and cite your pages in ChatGPT, Perplexity, Claude, and Google AI Overviews.

Domain

We check the root path (/) against each bot's user-agent. Root-path blocking is the most common cause of missing AI citations.

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