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name: use-environments description: "Use PettingZoo AEC and Parallel environments safely, including reset/step loops, action masks, rendering, seeding, and smoke checks." disable-model-invocation: true metadata: disco-role: operating license: NOASSERTION

Use Environments

Use this sub-skill when an agent needs to instantiate a PettingZoo environment, write a bounded random or policy rollout, choose between AEC and Parallel loops, handle action masks, diagnose step(None), run headless smoke checks, or reason about reset/step/render/close lifecycle.

Read Or Run

• Read references/aec-parallel-workflows.md when you need correct AEC and Parallel loop templates, return-value contracts, seeding notes, and validation tips.
• Read references/action-masking-and-rendering.md when you need to locate action masks, sample masked actions, choose render modes, or handle dead-agent None actions.
• Read references/troubleshooting.md when a rollout fails with reset-order, optional dependency, mask, termination/truncation, GUI, or cleanup issues.
• Run scripts/smoke_env_loop.py when you need a bounded CLI smoke check for a specific installed PettingZoo module and factory.

Route Elsewhere

• For optional environment family extras, missing family dependencies, ROMs, or family selection, use ../environment-families/SKILL.md.
• For wrappers, AEC/Parallel conversions, AgentSelector, average_total_reward, or save_observation, use ../wrappers-and-utilities/SKILL.md.
• For implementing a new PettingZoo environment, use ../custom-environments/SKILL.md.
• For framework training recipes, vectorization, or long-running learning jobs, use ../training-integrations/SKILL.md.

Default Stance

Prefer headless, bounded rollouts first: construct the environment with no GUI render mode, call reset(seed=...), step only live agents, keep a hard step budget, and always call close() in finally.