Geo Crawlers

AI Crawler Access Analysis Skill

Scope note: This skill covers robots.txt / meta-tag / HTTP-header crawler access. Two related jobs moved to the sibling geo-ai-index-access skill: (1) nosnippet / preview-control auditing (nosnippet, max-snippet legacy tags — a 9.2/10 GEO factor per the Zyppy meta-analysis, Jun 2026) and (2) Bing indexation + IndexNow setup (the hard prerequisite for ChatGPT — 87% of citations match Bing results). Use geo-ai-index-access for those; use this skill for the crawler allow/block map.

Purpose

This skill analyzes a website's accessibility to AI crawlers -- the bots that AI companies use to discover, index, and train on web content. If AI crawlers are blocked, the site's content cannot appear in AI-generated responses regardless of its quality. Crawler access is the foundational technical requirement for GEO.

Key Insight

As of early 2026, many websites inadvertently block AI crawlers through overly aggressive robots.txt rules, inherited from legacy SEO configurations. An Originality.ai 2025 study found that over 35% of the top 1,000 websites block at least one major AI crawler, and 5-10% block all AI crawlers. Blocking AI crawlers is the single fastest way to become invisible in AI-generated search results.

Complete AI Crawler Reference

Tier 1: Critical for AI Search Visibility (RECOMMEND: ALLOW)

These crawlers power the AI search products where users actively look for answers. Blocking them directly reduces your visibility in AI-generated responses.

GPTBot

• Operator: OpenAI
• User-Agent: GPTBot
• Full User-Agent String: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; GPTBot/1.2; +https://openai.com/gptbot)
• Purpose: Fetches content for ChatGPT's web browsing, plugins, and search features. Content accessed by GPTBot may be used to improve OpenAI models.
• Impact of Blocking: Content will NOT appear in ChatGPT Search results or be accessible when users ask ChatGPT to browse the web. This is the highest-impact AI crawler to allow.
• Recommendation: ALLOW -- ChatGPT has 300M+ weekly active users as of 2025. Blocking GPTBot removes your content from one of the largest AI search surfaces.

OAI-SearchBot

• Operator: OpenAI
• User-Agent: OAI-SearchBot
• Full User-Agent String: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; OAI-SearchBot/1.0; +https://docs.openai.com/bots/overview)
• Purpose: Specifically powers ChatGPT's search feature. Unlike GPTBot, content accessed by OAI-SearchBot is NOT used for model training -- only for live search results.
• Impact of Blocking: Content will not appear in ChatGPT's search results even if GPTBot is allowed.
• Recommendation: ALLOW -- This is a search-only crawler with no training implications. There is no strategic reason to block it.

ChatGPT-User

• Operator: OpenAI
• User-Agent: ChatGPT-User
• Full User-Agent String: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ChatGPT-User/1.0; +https://openai.com/bot)
• Purpose: Used when a ChatGPT user explicitly asks the model to visit a specific URL. Acts like a browser agent on behalf of the user.
• Impact of Blocking: ChatGPT cannot visit your pages when users ask it to read or summarize them. This prevents direct user-initiated traffic.
• Recommendation: ALLOW -- Blocking this bot prevents users who are actively trying to engage with your content from accessing it through ChatGPT.

ClaudeBot

• Operator: Anthropic
• User-Agent: ClaudeBot
• Full User-Agent String: ClaudeBot/1.0; +https://www.anthropic.com/claude-bot
• Purpose: Fetches web content for Claude's features including web search, citations, and analysis tools.
• Impact of Blocking: Content will not be accessible to Claude for web search or when users ask Claude to analyze specific URLs.
• Recommendation: ALLOW -- Claude is a major AI assistant with growing market share. Blocking ClaudeBot reduces your AI search footprint.

PerplexityBot

• Operator: Perplexity AI
• User-Agent: PerplexityBot
• Full User-Agent String: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; PerplexityBot/1.0; +https://perplexity.ai/perplexitybot)
• Purpose: Powers Perplexity's AI search engine, which provides sourced answers with direct citations and links back to source pages.
• Impact of Blocking: Content will not appear in Perplexity search results. Perplexity is one of the best referral traffic sources among AI search products because it always displays source links.
• Recommendation: ALLOW -- Perplexity drives actual referral traffic and always attributes sources. High-value AI crawler for publishers and businesses.

Tier 2: Important for Broader AI Ecosystem (RECOMMEND: ALLOW)

These crawlers serve large AI platforms or search ecosystems. Allowing them increases your content's reach.

Google-Extended

• Operator: Google
• User-Agent: Google-Extended
• Purpose: Controls whether Google uses your content for Gemini model training and AI Overviews improvement. CRITICAL NOTE: Blocking Google-Extended does NOT affect your Google Search rankings or your appearance in Google Search results. That is controlled by the standard Googlebot.
• Impact of Blocking: Content may not be used for Gemini training or to improve AI Overviews. However, your content can still appear in AI Overviews based on standard search indexing.
• Recommendation: ALLOW -- Blocking provides minimal content protection upside while reducing your presence in Google's AI features. Since it does not affect standard search ranking, the only reason to block is philosophical objection to training data usage.

GoogleOther

• Operator: Google
• User-Agent: GoogleOther
• Purpose: Used by Google for various non-search-ranking purposes including research, one-off crawls, and AI-related data collection.
• Impact of Blocking: Minimal impact on search rankings. May reduce presence in Google's AI research and experimental features.
• Recommendation: ALLOW -- Low risk, moderate potential benefit for AI feature inclusion.

Applebot-Extended

• Operator: Apple
• User-Agent: Applebot-Extended
• Purpose: Used by Apple to train and improve Apple Intelligence features, Siri, and Apple's AI products. Separate from standard Applebot (which powers Siri search and Spotlight Suggestions).
• Impact of Blocking: Content may not be used in Apple Intelligence features. Standard Siri and Spotlight functionality is unaffected (controlled by Applebot).
• Recommendation: ALLOW -- Apple Intelligence is integrated into all Apple devices (2B+ active devices). Presence in Apple's AI features has growing strategic value.

Amazonbot

• Operator: Amazon
• User-Agent: Amazonbot
• Full User-Agent String: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/600.2.5 (KHTML, like Gecko) Version/8.0.2 Safari/600.2.5 (compatible; Amazonbot/0.1; +https://developer.amazon.com/support/amazonbot)
• Purpose: Indexes content for Alexa answers and Amazon's AI features.
• Impact of Blocking: Content will not appear in Alexa voice responses or Amazon's AI-powered search features.
• Recommendation: ALLOW -- Relevant for voice search optimization. Lower priority than Tier 1 crawlers but no downside to allowing.

FacebookBot

• Operator: Meta
• User-Agent: FacebookBot
• Purpose: Used by Meta for AI features across Facebook, Instagram, WhatsApp, and Meta AI assistant.
• Impact of Blocking: Content may not be accessible to Meta AI. Link previews on Facebook/Instagram are handled by a different crawler and are unaffected.
• Recommendation: ALLOW -- Meta AI is embedded in apps with 3B+ combined users. Growing importance for AI visibility.

Tier 3: Training-Only Crawlers (ALLOW or BLOCK Based on Strategy)

These crawlers are primarily used for AI model training rather than live search features. Blocking them does not affect AI search visibility.

CCBot

• Operator: Common Crawl (nonprofit)
• User-Agent: CCBot
• Full User-Agent String: CCBot/2.0 (https://commoncrawl.org/faq/)
• Purpose: Builds the Common Crawl dataset, which is used as training data by many AI companies (Google, Meta, Stability AI, and others).
• Impact of Blocking: Content will not appear in future Common Crawl datasets. Does NOT affect any live AI search product.
• Recommendation: CONTEXT-DEPENDENT -- Allow if you want maximum long-term AI training presence. Block if you want to control training data usage. No impact on search visibility.

anthropic-ai

• Operator: Anthropic
• User-Agent: anthropic-ai
• Purpose: Used by Anthropic for AI safety research and Claude model training. Separate from ClaudeBot (which powers live features).
• Impact of Blocking: Content will not be used for Claude training. Does NOT affect Claude's live search or web browsing features (controlled by ClaudeBot).
• Recommendation: CONTEXT-DEPENDENT -- Similar to CCBot. Allow for training presence, block for training data control. No impact on live AI search.

Bytespider

• Operator: ByteDance
• User-Agent: Bytespider
• Purpose: Used by ByteDance for various AI products including TikTok's AI features and Doubao (their ChatGPT competitor in China).
• Impact of Blocking: Content will not be used for ByteDance AI products. Minimal impact for Western-market businesses.
• Recommendation: BLOCK for most Western businesses (aggressive crawling behavior reported, minimal search visibility benefit). ALLOW if targeting Chinese/Asian markets.

cohere-ai

• Operator: Cohere
• User-Agent: cohere-ai
• Purpose: Used by Cohere for model training. Cohere powers enterprise AI solutions and the Coral chat product.
• Impact of Blocking: Content will not be used for Cohere model training. Minimal direct consumer-facing impact.
• Recommendation: CONTEXT-DEPENDENT -- Low priority. Allow or block based on general training data stance.

Recommendation Matrix Summary

Maximum AI Visibility Configuration (robots.txt)

For sites wanting maximum AI search visibility:

# AI Crawlers - ALLOWED for AI search visibility
User-agent: GPTBot
Allow: /

User-agent: OAI-SearchBot
Allow: /

User-agent: ChatGPT-User
Allow: /

User-agent: ClaudeBot
Allow: /

User-agent: anthropic-ai
Allow: /

User-agent: PerplexityBot
Allow: /

User-agent: Google-Extended
Allow: /

User-agent: GoogleOther
Allow: /

User-agent: Applebot-Extended
Allow: /

User-agent: Amazonbot
Allow: /

User-agent: FacebookBot
Allow: /

# AI Crawlers - BLOCKED (aggressive/low value)
User-agent: Bytespider
Disallow: /

User-agent: CCBot
Disallow: /

Agent-Era Crawler Nuance (2026)

robots.txt is no longer the whole access-control story. Three developments change what "access" means in the agent era.

User-Triggered Fetchers Ignore robots.txt — By Design

Fetchers acting on a direct user request are NOT bound by robots.txt. Google documents this for its user-triggered fetchers — including Google-Agent (agent-mode fetcher) and the NotebookLM fetcher — and OpenAI's ChatGPT-User behaves the same way: when a user asks the assistant to read a specific URL, the fetch is treated as the user's own request, not a crawl (Google Search Central crawler docs; OpenAI bot docs). Implications:

• Blocking these user-agents in robots.txt does not reliably prevent single-URL, user-initiated reads. If a client truly wants to block them, enforcement must happen at the server (auth, paywall).
• Conversely, a user-triggered fetch is NOT an indexation channel — seeing Google-Agent or ChatGPT-User in the logs does not get content into AIO or ChatGPT Search. The Tier 1 crawlers above still control that. Do not report user-triggered fetches as a visibility win.

Web Bot Auth (RFC 9421): Signed Crawler Identity

User-agent strings are trivially spoofable. Web Bot Auth — the Cloudflare-led proposal built on RFC 9421 (HTTP Message Signatures) — lets legitimate crawlers cryptographically sign requests, so servers verify crawler identity from the signature instead of UA string + IP lists (Cloudflare / IETF draft, 2025).

• If the client's CDN/WAF supports signature verification, prefer it over UA-string rules — spoofed "GPTBot" traffic is common in log samples.
• When a client says "we block AI bots," check whether enforcement is UA-based (bypassable) or signature/IP-based before accepting the claim.

RSL 1.0: Machine-Readable Content Licensing

Really Simple Licensing (RSL) 1.0 (RSL Collective, official spec Dec 2025; steering members include Yahoo, Ziff Davis, O'Reilly) extends robots.txt with a License: directive pointing to an XML license document. It adds AI-specific usage categories — ai-all, ai-input, ai-index — so a publisher can allow search indexing while opting out of AI search applications, or demand pay-per-crawl / pay-per-inference compensation.

• ⚠️ Adoption flag: RSL 1.0 is a published standard with publisher momentum, but enforcement by major AI crawlers is NOT confirmed at scale. Treat it as a licensing-stance and monetization option, not as an enforcement mechanism.
• For visibility-maximizing sites (most GEO clients), RSL is usually out of scope — it matters when the client wants compensation or legal cover, not more citations.

Analysis Procedure

Step 1: Fetch and Parse robots.txt

1. Use WebFetch to retrieve [domain]/robots.txt.
2. Parse all User-agent directives and their associated Allow/Disallow rules.
3. For each AI crawler in the reference list above:
   • Check if there is a specific User-agent block for that crawler
   • Check if there is a wildcard (User-agent: *) block that would apply
   • Determine effective access: Allowed, Blocked, or Not Mentioned (inherits wildcard rules)
4. Note any Crawl-delay directives that may slow AI crawler access.
5. Check for Sitemap directives (AI crawlers use these for discovery).

Step 2: Check Meta Robots Tags

1. For a sample of 5-10 key pages, fetch the HTML and check for:
   • <meta name="robots" content="noindex"> -- blocks all bots
   • <meta name="robots" content="nofollow"> -- prevents link following
   • <meta name="robots" content="noai"> -- emerging tag to block AI use
   • <meta name="robots" content="noimageai"> -- blocks AI image training
   • Bot-specific meta tags: <meta name="GPTBot" content="noindex">
2. Record any page-level overrides of the robots.txt directives.

Step 3: Check HTTP Headers

1. For the same sample pages, check response headers for:
   • X-Robots-Tag: noindex -- HTTP header equivalent of meta noindex
   • X-Robots-Tag: noai -- HTTP header to block AI use
   • X-Robots-Tag: noimageai -- blocks AI image training
   • Bot-specific headers: X-Robots-Tag: GPTBot: noindex
2. Note that HTTP headers override meta tags and apply to non-HTML resources too.

Step 4: Check for AI-Specific Files

1. Check for /llms.txt (emerging standard for AI crawler guidance).
2. Check for /.well-known/ai-plugin.json (OpenAI plugin manifest).
3. Check for /ai.txt (proposed standard, similar to ads.txt for AI).
4. Record presence/absence and quality of each file.

Step 5: Assess JavaScript Rendering Requirements

1. Check if the site is a Single Page Application (SPA) or heavily JavaScript-rendered.
2. AI crawlers vary in their JavaScript rendering capabilities:
   • GPTBot: Limited JS rendering
   • ClaudeBot: Limited JS rendering
   • PerplexityBot: Limited JS rendering
   • Googlebot: Full JS rendering (but Google-Extended inherits this)
3. If critical content requires JS rendering, flag this as a potential issue.
4. Check for Server-Side Rendering (SSR) or Static Site Generation (SSG) as mitigations.

Output Format

Generate a file called GEO-CRAWLER-ACCESS.md:

# AI Crawler Access Report: [Domain]

**Analysis Date:** [Date]
**Domain:** [Domain]
**robots.txt Status:** [Found/Not Found/Error]

---

## Crawler Access Summary

| Crawler | Operator | Tier | Status | Impact |
|---|---|---|---|---|
| GPTBot | OpenAI | 1 | [Allowed/Blocked/Not Mentioned] | [Impact description] |
| OAI-SearchBot | OpenAI | 1 | [Status] | [Impact] |
| ChatGPT-User | OpenAI | 1 | [Status] | [Impact] |
| ClaudeBot | Anthropic | 1 | [Status] | [Impact] |
| PerplexityBot | Perplexity | 1 | [Status] | [Impact] |
| Google-Extended | Google | 2 | [Status] | [Impact] |
| GoogleOther | Google | 2 | [Status] | [Impact] |
| Applebot-Extended | Apple | 2 | [Status] | [Impact] |
| Amazonbot | Amazon | 2 | [Status] | [Impact] |
| FacebookBot | Meta | 2 | [Status] | [Impact] |
| CCBot | Common Crawl | 3 | [Status] | [Impact] |
| anthropic-ai | Anthropic | 3 | [Status] | [Impact] |
| Bytespider | ByteDance | 3 | [Status] | [Impact] |
| cohere-ai | Cohere | 3 | [Status] | [Impact] |

## AI Visibility Score: [X]/100

**Tier 1 Access:** [X/5 crawlers allowed]
**Tier 2 Access:** [X/5 crawlers allowed]
**Tier 3 Access:** [X/4 crawlers allowed]

---

## Critical Issues

[List any Tier 1 crawlers that are blocked]

## Recommendations

### Immediate Actions
[Specific robots.txt changes needed]

### robots.txt Recommendation

[Complete recommended robots.txt content for AI crawlers]

### Additional Technical Findings
- **Meta Robots Tags:** [Findings]
- **X-Robots-Tag Headers:** [Findings]
- **JavaScript Rendering:** [Assessment]
- **llms.txt:** [Present/Absent]
- **Sitemap Accessibility:** [Assessment]

Scoring for Crawler Access

The AI Crawler Access Score is calculated as:

Final score = sum of all weighted components, capped at 100.