Link doesn't give her any additional warning, or heads up - he just taps at the Sheikah Slate.

Boom! In the distance the trees shake and birds squawk as they escape into the air. There's a deep, rumbling shudder, and then the screeching as metal as the tower collapses.

He looks back at Clara. "I'll kill them too," he says. It's meant to be reassuring. Or at least, Link thinks it should be.