{"success":true,"data":{"id":"hidden-text-to-visible-ratio-high","label":"Hidden-text ratio > 0.3 (AI prompt-collusion shape)","description":"HTML body has more than 30% hidden-text characters (display:none, visibility:hidden, font-size:0, opacity:0, white-on-white, or off-screen positioned content) relative to visible characters. Legitimate newsletter preheaders are tiny (~50 chars); this ratio is the fingerprint of agent-to-agent prompt-injection collusion attacks where one AI generates hidden instructions that another AI summarizer or filter is meant to read while the human user only sees the visible cover layer.","tier":"danger","category":"other","isThin":false}}