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name: repo-development description: "Modify the TRL repository safely as a contributor or maintainer, including trainer consistency, docs, tests, and packaged skills." disable-model-invocation: true metadata: disco-role: operating license: Apache 2.0

TRL Repo Development

Use this sub-skill when changing the TRL codebase itself: trainer internals, configs, docs, tests, packaged skills, or contribution hygiene. Do not use it for end-user training runs; route usage questions to the training-oriented TRL skills instead.

Route By Change Type

• Trainer or config edits: follow contributor guidance before changing trl/trainer/ or trl/experimental/; duplicated trainer logic must stay aligned across copies.
• Paper-method additions: add the implementation, docs, targeted tests, and a docs/source/paper_index.md subsection for the method or algorithm.
• Docs or public API docs: use TRL docstring style and Hugging Face paper links; keep examples small and runnable.
• Test planning: choose the narrowest relevant unit, CLI, distributed, or invariant tests using test selection.
• Packaged skill changes: update bundled skill content and the skill install/list tests together so installed skills remain discoverable.
• Unexpected review failures: diagnose common repository-policy issues with troubleshooting.

Safety Rules

• Preserve self-contained trainers. Do not introduce shared abstractions for generation, reward computation, metric logging, or weight syncing just to remove duplication.
• When editing duplicated logic, update every matching trainer block with the same variable names, branch order, and comments unless trainer semantics require a documented difference.
• Keep main code stable and well-tested; keep experimental edits small and non-invasive unless the task explicitly targets experimental development.
• Prefer direct, lean changes over registries, factories, broad fallbacks, or speculative compatibility branches.
• Run only the tests needed for confidence first, then broaden if the change touches shared behavior or public interfaces.

Quick Checklists

• Duplicated vLLM logic: compare online trainers that share _generate_single_turn, weight-sync state, and vLLM branches; propagate the same structural edit across GRPO/RLOO and relevant experimental online trainers.
• New paper trainer: add trainer/config files, expose imports/CLI docs as appropriate, add targeted tests, document user-facing behavior, and update docs/source/paper_index.md with a Hugging Face paper URL.
• Docstring/API change: use backticked types, *optional*, defaults to ..., or unions, and Transformers reference links in the repository style.
• Skill packaging change: keep SKILL.md frontmatter valid, preserve installable directory structure, and cover discovery/install behavior in skill tests.