TLDR Tech / DevOps
Introducing Precursor: detecting agentic behavior with continuous client-side signals
Cloudflare Precursor is a client-side verification system that continuously monitors behavioral signals across entire user sessions to distinguish humans from bots. The tool uses dynamically injected JavaScript to analyze patterns like mouse movements, keyboard timing, and interaction rhythms across sessions—capturing nuances like wrist pivot arcs and cognitive delays that automated bots struggle to replicate consistently over time.
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