AI Crawler Atlas / domains
northernbrewer.com: AI crawler policy in robots.txt
robots.txt as fetched on 2026-10-10: northernbrewer.com disallows 13 of 22 AI and search crawlers from the site root: GPTBot, ClaudeBot, Google-Extended, CCBot, meta-externalagent, Bytespider, Applebot-Extended, Amazonbot, cohere-ai, Diffbot, omgili, Timpibot, PerplexityBot. That includes crawlers behind AI answers (PerplexityBot).
The file refuses training crawlers and also some crawlers that power AI answers, so the site is likely to be missing from AI citations and the referral traffic that follows.
This reports what the file asks. It does not show whether a crawler can actually reach the site: many sites also block crawlers at their CDN or firewall, and some crawlers ignore robots.txt.
Training crawlers
Disallowing these keeps a site's content out of future model training. It does not remove what was already collected.
| Crawler | Operator | Status | How the file treats it |
|---|---|---|---|
| GPTBot | OpenAI | disallowed | named in the file |
| ClaudeBot | Anthropic | disallowed | named in the file |
| Google-Extended | disallowed | named in the file | |
| CCBot | Common Crawl | disallowed | named in the file |
| meta-externalagent | Meta | disallowed | named in the file |
| Bytespider | ByteDance | disallowed | named in the file |
| Applebot-Extended | Apple | disallowed | named in the file |
| Amazonbot | Amazon | disallowed | named in the file |
| cohere-ai | Cohere | disallowed | named in the file |
| Diffbot | Diffbot | disallowed | named in the file |
| omgili | Webz.io | disallowed | named in the file |
| Timpibot | Timpi | disallowed | named in the file |
Search and citation crawlers
These feed AI answer engines that cite and link their sources. Disallowing them can take a site out of AI answers and out of the referral traffic that comes with them.
| Crawler | Operator | Status | How the file treats it |
|---|---|---|---|
| OAI-SearchBot | OpenAI | not disallowed | covered by the default rule |
| PerplexityBot | Perplexity | disallowed | named in the file |
| Claude-SearchBot | Anthropic | not disallowed | covered by the default rule |
| DuckAssistBot | DuckDuckGo | not disallowed | covered by the default rule |
User-action fetchers
These fetch a page live when a person asks an assistant about it. Disallowing them stops the assistant reading the page for that person.
| Crawler | Operator | Status | How the file treats it |
|---|---|---|---|
| ChatGPT-User | OpenAI | not disallowed | covered by the default rule |
| Perplexity-User | Perplexity | not disallowed | covered by the default rule |
| Claude-User | Anthropic | not disallowed | covered by the default rule |
| meta-externalfetcher | Meta | not disallowed | covered by the default rule |
Classic search crawlers
Classic search crawlers, shown as the baseline.
| Crawler | Operator | Status | How the file treats it |
|---|---|---|---|
| Googlebot | not disallowed | covered by the default rule | |
| Bingbot | Microsoft | not disallowed | covered by the default rule |
How northernbrewer.com compares
Among 65,831 readable sites in the Top 100,000, 12.9% disallow GPTBot, 10.8% ClaudeBot, 6.0% OAI-SearchBot and 7.9% PerplexityBot. Among 32,014 readable .com sites: 12.5% disallow GPTBot, 10.6% ClaudeBot.
History
First read 2026-10-10; the file has not changed since. Read the file itself.
The AI-related lines in the file
# OpenAI — training crawler (ChatGPT-User / OAI-SearchBot are allowed below) User-agent: GPTBot # (Claude-User / Claude-SearchBot are user-initiated and allowed below) User-agent: ClaudeBot User-agent: anthropic-ai User-agent: CCBot User-agent: Bytespider # Google Gemini / Vertex training opt-out (does NOT affect Googlebot search) User-agent: Google-Extended User-agent: Applebot-Extended User-agent: Amazonbot User-agent: Meta-ExternalAgent # Perplexity — bulk index crawler. (Perplexity-User user-initiated browse User-agent: PerplexityBot User-agent: cohere-ai User-agent: AI2Bot User-agent: AI2Bot-Dolma # Diffbot — structured-data extraction sold to AI builde
Check it live. This page shows the file as read on 2026-10-10. Run a live check of northernbrewer.com and get told when it changes, or get the dataset for a segment.