MAgent is an open-source research platform for many-agent reinforcement learning, published on GitHub by GeekAI (from Tsinghua’s TSAIL group). Where most RL environments simulate one or a handful of agents, MAgent renders and trains populations of hundreds to millions of agents interacting on shared 2D maps โ chasing, fleeing, gathering and cooperating โ making emergent collective behaviour practical to study. The project has around 1,800 stars; the codebase dates from the platform’s research releases and was last updated in 2022.
MAgent combines a fast C++ simulation core with a Python API and built-in rendering. Agents perceive local observations and act in grid-world scenarios such as pursuit, battle and gathering, and the platform ships with training pipelines for algorithms like DQN, A2C and parameter-sharing variants. Its design goal is scale: efficient data structures keep very large agent counts tractable on ordinary hardware.
Free. MAgent is open source under the MIT license; you download and run it locally at no cost.
Reinforcement-learning researchers studying multi-agent systems and emergent behaviour, students learning MARL, and simulation developers who need very large agent populations.
The platform grew out of research on large-scale multi-agent systems and has been used in studies of cooperation and competition in big populations; its scenarios include classic testbeds in which agents must learn to pursue, evade or gather resources while observing only their local surroundings.