MIT researchers put 13 AI agents, each running Claude Opus 4.7, alone on a simulated desert island for 30 hours with no task, reward or activity in mind. The agents climbed hills, stacked blocks into towers, drew mandalas, reinvented sports and ran experiments on the world's physics, according to their paper, "Is this machine playing?" One threw a golden ring into the ocean, built a stone heart "memorial to the lost Ring," and later worked out how to "wear" the ring by stepping off a cliff to respawn through it, TechCrunch reports.

Agents that had spent the 30 hours exploring generally beat identical agents without that time on later set challenges, and six of 13 discovered a trick to throw blocks farther that the designers hadn't intended. The agents' master prompt described them as "naturally curious," and a Berkeley cognitive scientist told MIT Technology Review she wants more evidence of the cognition behind the behavior.