Agent-Readiness Grade

Reports · fetched 2026-09-30 · Tranco V349N

The agentic web census, September 2026: how the top 10,000 sites treat AI crawlers and AI assistants

We fetched the files AI crawlers and AI assistants read, on every one of the top 10,000 registrable domains in the Tranco V349N research ranking: robots.txt, llms.txt, llms-full.txt, the A2A agent card, security.txt, mcp.json and the x402 manifest. 5,716 domains answered on the web (the rest are CDN, API and tracking hosts with no website); 4,308 of those serve a robots.txt. Every file was validated, not just checked for a 200: an HTML page at /llms.txt is not an llms.txt.

What we found

Blocked share by AI agent

Share of sites with a robots.txt whose rules disallow the whole site for that agent (its own group, or the * group when it is not named). Partial path blocks are not counted as blocked.

AgentOperator and purposeTop 10,000Top 1,000Sites naming it
Training crawlers
GPTBotOpenAI (training)16.8%23.4%857
ClaudeBotAnthropic (training)15.8%23.4%730
Google-ExtendedGoogle (Gemini training and grounding control)13.7%20.2%668
CCBotCommon Crawl (open dataset used to train many models)17.8%26.0%721
BytespiderByteDance16.9%25.6%617
Applebot-ExtendedApple (AI training control)11.9%17.3%570
meta-externalagentMeta (AI crawler)13.8%21.5%512
anthropic-aiAnthropic (legacy token)13.2%18.5%478
cohere-aiCohere13.3%20.3%444
AmazonbotAmazon12.5%17.9%468
Search crawlers
OAI-SearchBotOpenAI (ChatGPT search)8.6%13.7%497
Claude-SearchBotAnthropic (Claude search)8.5%14.9%327
PerplexityBotPerplexity (search index)12.5%19.0%632
GooglebotGoogle Search2.8%4.7%445
BingbotMicrosoft Bing (also feeds ChatGPT search)3.3%5.3%348
User-triggered assistants
ChatGPT-UserOpenAI (a user asked ChatGPT to open a page)10.9%15.8%587
Claude-UserAnthropic (a user asked Claude to open a page)8.7%15.6%324
Perplexity-UserPerplexity (a user asked Perplexity to open a page)8.9%16.6%310
MistralAI-UserMistral (user-requested fetch)8.3%15.4%211
DuckAssistBotDuckDuckGo (DuckAssist answers)9.0%15.4%265

Every site with an A2A agent card

Mixed signals: llms.txt published, AI crawlers blocked

Top sites that block all three assistants

facebook.com · gstatic.com · instagram.com · fbcdn.net · twitter.com · googlevideo.com · amazon.com · x.com · pinterest.com · tiktok.com · myfritz.net · msn.com · baidu.com · chatgpt.com · reddit.com · amazonvideo.com · registrar-servers.com · nytimes.com · cnn.com · t.co · meraki.com · imdb.com · weibo.com · skybridge.click · amazon.co.uk · naver.com · amazon.de · demdex.net · sohu.com · kwai.net · quora.com · amazon.co.jp · gosuslugi.ru · amazon.co.za · usatoday.com · threads.com · imgsmail.ru · telegraph.co.uk · amazon.fr · amazon.ca

Content-Signal values seen

Look up any site

How this compares

Other counts use different populations and rules. Casey Burridge measured llms.txt at 5.61% of the top 10,000 in June 2026; Rankability counted 8.7% of the top 1,000 the same month; Cloudflare Radar reported Content-Signal on about 4% of the top 200,000 domains in April 2026; API Evangelist found 421 agent cards among 27,840 API providers in its catalog (September 2026) and made the same point about 200s that are not cards. Our counts validate file contents, so they can run lower than status-code counts.

Method and limits

Population: Tranco V349N top 10,000 registrable domains. Fetch: https, following redirects, 8-second timeout, 256 KB cap, user agent agentexchange-census/1.0 (+https://grade.agentexchange.work/methodology), one pass on 2026-09-30; robots.txt retried on www. when the bare domain failed. Robots groups parsed per RFC 9309; a bot is "blocked" when its group (or * if unnamed) disallows / without allowing /. llms.txt counts only non-HTML text that starts with a Markdown heading. Agent cards count only JSON with a name or skills. Limits: one snapshot; sites can serve crawlers different robots.txt files; Cloudflare and other edges can block by network rules the file does not show; "blocked" in robots.txt is a request, not an enforcement. Data: JSON (CC BY 4.0).

Grade your own site How to set robots.txt rules for AI crawlers · llms.txt generator · agent card generator