MuJoCo

Begin with a small model and the viewer

The release README offers versioned binaries for Linux x86-64/AArch64, Windows x86-64 and universal macOS. The Python route requires Python 3.10 or newer; the mujoco package includes the engine library, so a separate engine download is unnecessary for that route. The documented python -m mujoco.viewer command opens a viewer that can load a model. Interactive visualization also needs a working OpenGL rendering context; this review does not establish a particular GPU requirement. These are upstream setup instructions, not an installation tested by this publication. [S001] [S005] [S006]

The native modeling language is MJCF XML, and URDF files can also be loaded. A model compiles into mjModel; mjData stores evolving state and intermediate results. Keep the editable model source alongside its assets instead of treating a compiled MJB file as a portable interchange format: MJB files are version-specific. [S005]

Python has both a blocking managed viewer and a passive viewer that lets the user's code continue. In the passive route, the script is responsible for advancing the simulation and synchronizing viewer state. On macOS that route requires the provided mjpython launcher. This distinction matters when moving from visual inspection to a custom control loop. [S006]

An upgrade is an experiment change

MuJoCo's versioning document uses a custom scheme from 3.5.0 onward: the middle version component may introduce breaking changes, while the final component can add features or fixes. It explicitly does not guarantee numerical reproducibility across versions. Record the engine version with the model and rerun the experiment's own checks after an upgrade; a package that still imports is not evidence that a trajectory remains equivalent. [S007]

The engine can support control synthesis, system identification and learning experiments, but the usefulness of those results depends on the selected model and validation procedure. No performance benchmark, contact-parameter calibration or transfer to hardware was performed in this review. [S005]

Separate engine, documentation and model rights

Source code is Apache-2.0. The README separately assigns reStructuredText documents, images and videos in the documentation directory to CC-BY-4.0. Those declarations do not automatically license an independently acquired robot mesh, dataset or trained policy. This profile selects the engine and its documentation, not a complete learning workload or robot asset collection. [S001] [S003]