Beijing – September 12, 2026 -- ModelBest, a Chinese AI startup, has released MiniCPM5-2B, a 2-billion-parameter open-source language model that ranks first on the Artificial Analysis Intelligence Index among open-source models under 4 billion parameters. The model, built in collaboration with the OpenBMB open-source community, also scored 20 on the Agentic Index, a metric measuring autonomous task-execution capability, outpacing peers in its size category.