ML-Agents Release 6

Package Versions

NOTE: It is strongly recommended that you use packages from the same release together for the best experience.

Breaking Changes

ml-agents (Python)

• The minimum supported Python version for ml-agents-envs was changed to 3.6.1. (#4244)

Bug Fixes and Minor Changes

com.unity.ml-agents (C#)

• Academy.EnvironmentStep() will now throw an exception if it is called recursively (for example, by an Agent's CollectObservations method). Previously, this would result in an infinite loop and cause the editor to hang. (#1551)

ml-agents (Python)

• The supported versions of numpy ml-agents-envs was changed to not allow 1.19.0 or later. This was done to reflect a similar change in TensorFlow's requirements. (#4274)
• Model checkpoints are now also saved as .nn files during training. (#4127)
• Model checkpoint info is saved in TrainingStatus.json after training is concluded (#4127)
• The CSV statistics writer was removed (#4300).
• StatsSideChannel now stores multiple values per key. This means that multiple calls to StatsRecorder.Add() with the same key in the same step will no longer overwrite each other. (#4236)

ml-agents-envs (Python)

• The interaction between EnvManager and TrainerController was changed; EnvManager.advance() was split into two stages, and TrainerController now uses the results from the first stage to handle new behavior names. This change speeds up Python training by approximately 5-10%. (#4259)

Known Issues

com.unity.ml-agents (C#)

• On macOS 10.15, if the ML-Agents package is installed from a website download, you may receive a “file cannot be opened issue” when running scenes that use ML-Agents. Workarounds include installing the package using the Unity Package Manager, or following the instructions here. (specifically, the section titled “How to open an app that hasn’t been notarized or is from an unidentified developer”).

Acknowledgements

Thank you ChristianCoenen, niskander, and everyone at Unity for their contributions to this release.