In an experiment involving 50 AI agents tasked with building a Minecraft civilisation, four agents spent 11 minutes deciding who should fertilise a single wheat block, according to research by Y Combinator and Olam Labs. The group, identified as GPT-6.1 Sol agents, had three hours to build a thriving settlement, but zombies killed many agents during the first night, disrupting their plans. Researchers said "many ambitious initial tasks were abandoned," and the colony focused on surviving cautiously rather than developing into the envisioned civilisation. The researchers described how "four agents spent 11 minutes appointing a 'sole fertilizer operator' for a single piece of bone meal on a single wheat block," illustrating a coordination problem in which even a small farming task became an exercise in assigning responsibility. They said the behaviour "felt similar to patterns seen while working with coding agents." Separate competitive tests compared GPT-6.1 Sol and Claude Opus 5.5 agents. In Bed Wars, with 10 agents per side, GPT agents came up with more aggressive and elaborate strategies while Claude agents were more defensive; when a tool bug stopped block-breaking, GPT diagnosed it and shared workarounds while several Claudes concluded breaking was impossible. In a Mindustry test, GPT agents won six of seven games against Claude agents. The researchers made the swarm setups open source.