nonexistent-path control
A request for a randomised URL that no site would ever publish, made alongside the real requests. It is the control that tells a scanner whether it reached the site at all: a real site answers it differently from its homepage.
What nonexistent-path control means
Tightened on 1 September 2026 to catch walls that answer with non-HTML, a challenge page of any size, or a block page byte-identical across paths.
Definitions that name nonexistent-path control
Related terms in Crawlers and access
Who is fetching, whether they are who they claim, and what your rules actually permit.
visitor resolve · published crawler ranges · operator origin · signed agent · agent arrival · agent conduct record · agent traffic index · user-triggered fetch exemption · retrieval crawler · user-triggered fetch · verified crawler · forged crawler identity · unverifiable · robots.txt · user-agent group · AI opt-out · Content-Signal · crawl budget · cloaking · challenge page at 200 · uniform refusal · blocked render resource · off-host redirect · homepage refused · FCrDNS · Crawler trap · Conditional request · ASN blocking · operator feed · residential proxy · Google-Extended · Google-Agent · GPTBot vs OAI-SearchBot · ClaudeBot vs Claude-User · PerplexityBot vs Perplexity-User · CCBot · Bytespider · agentic traffic · crawler classification · user agent · datacenter IP · vantage point · rate limit · delivery comparison · honeypot
Questions about nonexistent-path control
What is nonexistent-path control?
A request for a randomised URL that no site would ever publish, made alongside the real requests. It is the control that tells a scanner whether it reached the site at all: a real site answers it differently from its homepage.
Which area of the glossary does nonexistent-path control belong to?
Crawlers and access: Who is fetching, whether they are who they claim, and what your rules actually permit.
← uniform refusal · blocked render resource →
See it in the full glossary · 772 terms across 19 areas.
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