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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.

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