AI crawler access check

One wrong line in robots.txt removes a site from AI answers completely, and no amount of content work can compensate. This check takes under a minute and should run before any other AI-visibility work.

Scope

Read https://<domain>/robots.txt and nothing else. Do not crawl the site, do not attempt to access disallowed paths, and do not bypass any access control. This is a read of one public file.

Procedure

1. Fetch

Fetch https://<domain>/robots.txt.

• 404 or empty - everything is allowed by default. Say so; that is a valid and often correct configuration. Stop and report.
• Non-200 other than 404, or unreachable - report the status code and stop. Do not guess at contents.
• Served as HTML (a soft 404 returning the site's error page) - flag it. Crawlers may parse it as garbage. This is itself a finding.

2. Resolve each agent

For each agent below, apply standard robots.txt matching: the most specific User-agent group that names the agent wins, and * applies only when no group names it. Within the winning group, the longest matching path rule wins, and Allow beats Disallow on an equal-length match.

Agent	Operator	Purpose	What blocking it actually costs
OAI-SearchBot	OpenAI	search index	citations in ChatGPT Search
ChatGPT-User	OpenAI	live fetch during a chat	the model cannot open your page when a user asks about it
GPTBot	OpenAI	training	background model knowledge, not search citations
PerplexityBot	Perplexity	search index	Perplexity citations
Perplexity-User	Perplexity	live fetch during a query	live page reads
ClaudeBot	Anthropic	index and training	Anthropic-side retrieval
Googlebot	Google	main index	AI Overviews and AI Mode, plus normal search
Google-Extended	Google	Gemini grounding and training	Gemini grounding only - not AI Overviews
Bingbot	Microsoft	Bing index	Microsoft Copilot, which rides the Bing index
Applebot	Apple	index	Apple search surfaces
Applebot-Extended	Apple	training	Apple Intelligence training only
CCBot	Common Crawl	open crawl corpus	an input to many downstream models

Crawler names change and new ones appear. Before finalizing, check each operator's own published crawler documentation for agents added or renamed since this list was written, and include them. State which list you used.

3. Report

Produce a table with one row per agent and exactly these columns:

Agent | Verdict (ALLOWED / BLOCKED / PARTIAL) | Rule responsible | Impact

• Rule responsible must quote the literal line from robots.txt, or say no matching rule - allowed by default. Never state a verdict without the line that produced it.
• PARTIAL means important paths are disallowed while the site root is allowed. Name the disallowed paths.

Then give:

• Verdict - one sentence: is this site reachable by AI answer engines, or not?
• What to change - the exact robots.txt lines to add, remove, or edit, as a code block the user can paste. If nothing needs to change, say that plainly rather than inventing work.
• What this check did not cover - robots.txt is only the first gate. Server-side blocking by WAF, CDN bot rules, IP reputation, or Cloudflare bot management can block a crawler that robots.txt allows, and none of that is visible in this file. Say so every time.

Three mistakes this check exists to catch

1. Blocking GPTBot to opt out of training, and assuming that is the whole story. It is not. OAI-SearchBot governs whether a site can be cited in ChatGPT Search, and it is a separate agent with a separate rule. Blocking one does not block the other, in either direction.
2. Blocking Google-Extended to stay out of AI Overviews. It does not do that. AI Overviews and AI Mode are built on the normal Googlebot index. Blocking Google-Extended opts out of Gemini grounding and training and has no effect on AI Overviews. To leave AI Overviews, the mechanism is the nosnippet, max-snippet, or data-nosnippet family, and it costs normal search snippets too. Say that tradeoff out loud rather than letting the user discover it later.
3. A blanket User-agent: * / Disallow: / inherited from a staging config, a bot-mitigation template, or a security hardening guide. This is common and almost always unintentional on a production marketing site.

If the user asks whether they should block AI crawlers

Do not answer with a recommendation. Lay out the tradeoff and let them decide: allowing search crawlers is what makes citation possible, allowing training crawlers affects model knowledge but not citation, and the two decisions are independent. Publishers with a licensing position and companies that want to be recommended by AI assistants land in different places, and both are legitimate.

---

About

Maintained by MaxAEO — https://maxaeo.ai — which works on AI answer-engine visibility. The crawler matrix used here is kept current against each operator's own published crawler documentation; where an agent has no official documentation, this skill says so rather than guessing.

This check is free, read-only, and runs on one public file. It does not require an account, an API key, or any paid service.