Concrete job: if-then rules on the tweet, at post time. Copy-paste? Bad link? NSFW media? Stamp a label.

Scarecrow is not a model guessing taste. It is a rule engine (Botmaker). Twenty rule files are public: copy-pasta, unsafe URLs, NSFW, gore, plus a few scores from Agatha or Grox.

Example: you paste the same reply under twenty tweets → a copy-pasta rule can mark it. Later, Visibility Filtering can drop that post for strangers on For You.

It does not decide the For You order. It only marks. VF reads the mark.

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