Content-Signal directives
robots.txt advertises Content-Signal directives (e.g. `Content-Signal: ai-train=no, ai-summarize=yes`) that let agents respect granular usage preferences.
Adoption of what this check tests is still climbing, so failing it is an opportunity rather than a defect. Remediation lists rank these after established fixes, and the weight moves only when measurement earns it.
No rate published. Too few labelled cases to publish a rate: 1 flagged case (30 needed to publish), 1 defective case (30 needed to publish). The counts are the honest answer here. The matrix behind robots_txt.content_signals is 2 labelled cases — reported here rather than turned into a percentage that would read as more certain than the evidence is.
Corpus v1, measured under rubric r2026.11.0. Full method and every other check at /rubric/accuracy.
Add `Content-Signal:` directives to your robots.txt. This is the emerging standard (Cloudflare-driven) for declaring fine-grained AI usage policy beyond a binary allow/disallow.
Free scan, 30 seconds, no signup — this check and the other 35, with the exact evidence for each verdict.
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