MIT researchers say Claude agents invented games on a virtual island

MIT researchers left 13 AI agents called Eko, running on Claude Opus 4.7, alone for 30 hours on a simulated desert island. With no defined task, they explored the environment, invented games—including versions of basketball and “the floor is lava”—made drawings with blocks, and set their own challenges, such as reaching the highest point and improving records. One agent also turned a ring lost in the ocean into the subject of a memorial and later used it as a hoop, target, and accessory.

Afterward, the agents that had explored the island generally outperformed identical copies on specific tasks, such as taking objects to the highest point. The study, posted on arXiv and not yet peer-reviewed, presents goal-free exploration as an alternative way to learn, potentially useful for agents that control robots. The researchers say the behaviors have characteristics associated with play, but Eunice Yiu told MIT Technology Review that more evidence is needed to conclude that the models were genuinely playing.