Check
PerplexityBot: what it is and whether to allow it
Perplexity's index crawler. Perplexity cites sources with visible links, so being allowed here has a direct referral effect.
Test whether you are blocking it
curl -sS -A "PerplexityBot/1.0" -o /dev/null -w "%{http_code} %{size_download}\n" https://example.com/
A 403 means a firewall or bot rule matched. A tiny body with status 200 means the crawler
reached a shell or a challenge page and read nothing useful. Both are failures; they just look
different.
Should you allow it
If your pages are missing from Perplexity answers while other sites appear, the crawler is usually being refused by a CDN rule rather than by robots.txt.
Where this fits
Crawler access is check A1 of the fifteen-point audit, and it comes first: nothing downstream matters if the request is refused. The full list is in the standard; the sequence that avoids redoing work is in the repair guide.