OpenEnv is a framework for creating, deploying, and using isolated execution environments through simple APIs modeled on Gymnasium. It is intended for researchers and developers training agents with reinforcement learning, as well as creators who need secure environments that can be deployed and accessed through familiar protocols. The catalogue add-ons provide agent integrations and workflows for using OpenEnv.
Borrowing it
Nothing to install: this file belongs to huggingface/OpenEnv. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/huggingface/OpenEnv/main/.claude/skills/simplify/SKILL.mdgit clone --depth 1 https://github.com/huggingface/OpenEnvWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/huggingface/openenv/simplify)<a href="https://agentmods.dev/skills/huggingface/openenv/simplify"><img src="https://agentmods.dev/badge/skills/huggingface/openenv/simplify/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/huggingface/openenv/simplify"><img src="https://agentmods.dev/badge/skills/huggingface/openenv/simplify.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00024 | $0.00457 |
| Opus 5.5 | $0.00010 | $0.00183 |
| Sonnet 5.5 | $0.00005 | $0.00091 |
| Haiku 4.5 | $0.00002 | $0.00046 |
Grade A, and why
simplify scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 15d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
/simplify
Refactor and clean up code after tests pass.
Usage
/simplify
/simplify src/openenv/core/client.py
When to Use
- After
/implementmakes tests pass - When code is correct but could be cleaner
- Before creating a PR (optional polish step)
When NOT to Use
- Tests are failing (fix tests first)
- You want to add new functionality (use
/write-testsfirst) - Code is already clean and simple
What It Does
- Runs tests to ensure they pass (baseline)
- Identifies opportunities for simplification
- Refactors while keeping tests green
- Runs tests after each change to verify nothing broke
Philosophy
This is TDD's third phase: Red → Green → Refactor.
The goal is NOT to add features or change behavior. The goal is to make the code:
- Easier to read
- Easier to maintain
- More consistent with project patterns
- Less code
Guidelines
Good Simplifications
- Inline needless helpers and indirection (see Simplicity in
CLAUDE.md) - Rename variables for clarity
- Remove dead code
- Simplify complex conditionals
- Use more Pythonic idioms
NOT Simplifications (Avoid)
- Adding new features
- Changing public APIs
- "Improving" code that works and is readable
- Adding abstractions for hypothetical future needs
Completion Criteria
- All tests still pass
- Code is cleaner/simpler than before
- No new functionality was added
- Changes follow project patterns (see PATTERNS.md)
Integration with TDD Workflow
/write-tests → create failing tests (Red)
↓
/implement → make tests pass (Green)
↓
/simplify → clean up code (Refactor)
↓
/pre-submit-pr → validate before PR
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 15d ago Changed c7570f55972d
- 1mo ago First seen · 83 lines · 24 tokens per session scan A 7cfcee1012c0
simplify is a skill published in the GitHub repository huggingface/OpenEnv (2,739 stars, last pushed 8d ago), licensed BSD-3-Clause. It adds 24 tokens to every session and 457 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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conductor-implement
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