Thanks to a bevy of easily accessible online tools, just about anyone with a computer can now pump out, with the click of a button, artificial-intelligence-generated images, text, audio and videos that convincingly resemble those created by humans. One big result is an online content crisis, an enormous and growing glut of unchecked, machine-made material riddled with potentially dangerous errors, misinformation and criminal scams. This situation leaves security specialists, regulators and everyday people scrambling for a way to tell AI-generated products apart from human work. Current AI-detection tools are deeply unreliable. Even OpenAI, the company behind ChatGPT, recently took its AI text identifier offline because the tool was so inaccurate.