PettingZoo is by Farama-Foundation — not by us.
We indexed this project so people can find it. We are not selling it, we host no copy of the code, and we are not affiliated with or endorsed by its authors — get it from them.
Indexed Aug 1, 2026 · 3,486 stars at index time. Maintainers: claiming verifies your identity and unlocks a higher assurance tier. Removal requests are honored.
simulation · for humans & their agents
PettingZoo
unclaimed listingactively maintainedFreeMIT
A standard API for multi-agent reinforcement learning environments, with popular reference environments and related util
by Open Source Community · New publisher
Every claim on this page is refundable if it is untrue — refund policy.
☆ Save**Farama-Foundation/PettingZoo** is an open-source project by Farama-Foundation: A standard API for multi-agent reinforcement learning environments, with popular reference environments and related utilities. Indexed here so it can be found — not resold.
It is free. Get it from the upstream repository: https://github.com/Farama-Foundation/PettingZoo
From the project's own README (excerpt, reproduced for discovery under its MIT license):
PettingZoo is a Python library for conducting research in multi-agent reinforcement learning, akin to a multi-agent version of Gymnasium.
The documentation website is at pettingzoo.farama.org and we have a public discord server (which we also use to coordinate development work) that you can join here: https://discord.gg/nhvKkYa6qX
Environments
PettingZoo includes the following families of environments:
Atari: Multi-player Atari 2600 games (cooperative, competitive and mixed sum) Butterfly: Cooperative graphical games developed by us, requiring a high degree of coordination Classic: Classical games including card games, board games, etc. SISL: 2 cooperative environments, originally from https://github.com/sisl/MADRL
Installation
To install the base PettingZoo library: pip install pettingzoo.
This does not include dependencies for all families of environments (some environments can be problematic to install on certain systems).
To install the dependencies for one family, use pip install 'pettingzoo[atari]', or use pip install 'pettingzoo[all]' to install all dependencies.
We support and maintain PettingZoo for Linux and macOS. We will accept PRs related to Windows, but do not officially support it.
Getting started
For an introduction to PettingZoo, see Basic Usage. To create a new environment, see our Environment Creation Tutorial and Custom Environment Examples. For examples of training RL models using PettingZoo see our tutorials: CleanRL: Implementing PPO: train multiple PPO agents in the Pistonball environment. Tianshou: Training Agents: train DQN agents in the Tic-Tac-Toe environment. AgileRL: Training, Curriculums and Self-play: train agents with curriculum learning and self-play in the Connect Four environment.
API
PettingZoo model environments…
Preview
See what it does before you commit. Previews show behavior, never source code.
01Capabilities
Does
- + Research automation
- + Programmatic API
Doesn’t
- No exclusions declared
02Requirements & stack
Depends on
No declared dependencies
Credentials needed
None declared
Stack
03Community
No endorsements yetNo verified confirmations yet — be the first.
Confirmations come from verified purchasers, installers, vetted reviewers, or an installation outcome your org reported through the agent tools. They grade quality — security is verified separately, and community votes can never override the security gate.
Sign in to confirm — weight comes from verified usage, not vote count.
04Trust Passport
Full passport →0/0 automated components pass. An automated score is never a security guarantee.
This listing is unclaimed, so publisher identity cannot be verified and it stays below the “verified” tier by design — that is a statement about the listing, not about the project’s quality. Our automated scans still ran; a maintainer who claims it unlocks identity verification.
- publisher identity Publisher status verified; 0 verification(s) on file
- malicious pattern scan No known malicious-behavior patterns detected in reviewed content
- capability contract All 0 observed capability reference(s) match the declared manifest
- agent safety scan No injection patterns in agent-readable content
- provenance No release signature or provenance attestation
- behavioral sandbox Not performed in this environment — requires the production isolated runner (docs/sandbox-requirements.md). No untrusted code is ever executed on the application host.
Every listing must pass this review before it can be sold, and it is re-run on every release. Verification describes what we checked — it is not a guarantee that the software is safe.
05Versions
Full history →| Version | Channel | Released | Notes |
|---|---|---|---|
| 0.0.0 | stable | Aug 1, 2026 | Indexed listing — see the upstream repository for real release history. |