Prompt injection can be caught by watching the neurons that fire when it happens, so a defence no longer depends on the model reporting the attack.

Creator of Claude Code at Anthropic

it's it's literally we're looking at neurons in the model's brain that light up when prompt injection happens. So the model won't even tell you but we can actually see those neurons and we can figure out and diagnose that it's happening. And then you combine that with the auto mode classifier and with these three layers we just cannot demonstrate prompt injection anymore.