Benchmarking Agent Safety in Browsers

To protect agents, we need a defense layer that sits between the raw HTML and the agent's context.

Architecture of a Defense System#

Interceptor#

A proxy or browser extension that captures the DOM before the agent processes it.

Scanner#

A lightweight model or heuristic engine that scans for "injection-like" patterns.

Sanitizer#

Removes or neutralizes suspicious segments before passing the safe DOM to the agent.

The Performance Challenge#

Scanning every DOM element introduces latency. A key engineering challenge is balancing safety (catching all attacks) with speed (not slowing down the browsing experience).