What are Content Signals?
Also: Content-Signal robots.txt directive
Content Signals is a robots.txt extension, introduced by Cloudflare in 2025, that lets a site state how its content may be used: search, ai-input (answers) and ai-train (training), each yes or no. It expresses preferences in addition to crawler rules. It is a young proposal, so not every crawler honours it.
Example
A line such as Content-Signal: search=yes, ai-input=yes, ai-train=no says you accept search and answer use but not training. Check each provider's documentation to see whether it reads the signal.
Example: Content-Signal: search=yes, ai-input=yes, ai-train=no accepts search and answer use but declines training.
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