Agent Web Index › onthisday.com
Can AI assistants read onthisday.com?
Measured on 2026-09-19 by asking the site 7 times — once as a browser, once as each of the 6 crawlers that feed ChatGPT, Claude, Perplexity, Gemini, Meta AI, Apple Intelligence and Doubao — and comparing what came back. The AI-training opt-out tokens that never crawl are read from robots.txt instead.
D50 / 100
0 of 6 crawlers can read this page.
More readable than 7% of the 47,315 sites measured so far.
Structured data: Organization, WebSite.
What each crawler got back
| Crawler | HTTP | Result | robots.txt |
|---|---|---|---|
| ClaudeBot (Claude) | 403 | challenged | blocked |
| GPTBot (ChatGPT) | 403 | challenged | blocked |
| OAI-SearchBot (ChatGPT Search) | 402 | error | allowed-by-star |
| PerplexityBot (Perplexity) | 402 | error | blocked |
| Google-Extended (Gemini, AI Overviews) a robots.txt token, not a crawler: it controls how already-crawled pages may be used, and never makes a request of its own | — | opted out in robots.txt | blocked |
| Meta-ExternalAgent (Meta AI) | 403 | challenged | blocked |
| Amazonbot (Alexa, Rufus) | 403 | challenged | blocked |
Cloudflare answers for this domain. Where a crawler above is refused while robots.txt allows it, the rule is applied by that edge, not written by the site — see how often each edge does this.
What to change, in order
- Let in the 1 crawler your own robots.txt already allows+1 crawlerOAI-SearchBot is turned away before reading the page (answered with an HTTP error), while robots.txt permits it — so this block is not written in your site. Cloudflare answers for this domain. Cloudflare applies AI-crawler blocking at the edge, independently of robots.txt (Security → Bots, plus the managed robots.txt feature). https://developers.cloudflare.com/bots/concepts/bot/ Fixing it takes this domain from 0 to 1 of 6 crawlers.
- Publish sitemap.xml and llms.txtsitemap.xml and llms.txt are missing, so an assistant has to discover the site by following links. llms.txt is the emerging convention for telling an assistant which pages actually matter.
- 5 crawlers are named and refused in robots.txt — a deliberate choiceClaudeBot, GPTBot, PerplexityBot, Meta-ExternalAgent, Amazonbot are blocked by a rule that names them. Nothing to fix here: this page records what is true, not what should be. It is listed so the deliberate part of the block is not confused with the accidental part above.
The checks
- Answers AI agents like it answers people14%
- Readable without JavaScript100%
- robots.txt lets the crawlers in14%
- Facts in JSON-LD84%
- Content reachable, not buried70%
- Publishes a map of itself0%
- Plain structure88%
Sites with a similar score
Embed this score
Put the badge on onthisday.com — it links back here, and re-measures every time this index re-crawls.
<a href="https://shop.lumnika.com/ai-readiness/onthisday.com"><img src="https://shop.lumnika.com/ai-readiness/onthisday.com/badge.svg" alt="AI readability"></a>
Method. 7 live HTTP requests (one per crawler, one as a browser) plus robots.txt, llms.txt, sitemap.xml and security.txt, 12-second timeout each,
from a single vantage point. Blocking AI crawlers is a legitimate choice, not a failure: this page records what is true, not what should be.
Domain comes from a shop-platform seed (Shopify/WooCommerce/Magento/BigCommerce/Shopline fingerprint or JSON-LD price), not the Tranco traffic ranking. One page per domain — the homepage — is audited.
Part of the Agent Web Index, 47,315 domains measured, updated continuously.
Part of the Agent Web Index, 47,315 domains measured, updated continuously.