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+# RFC 239: Policy on LLM assistance in contributions
+
+## Summary
+
+Introduce guidelines for acceptable use of large-language models when
+contributing to web-platform-tests.
+
+## Background
+
+[#202 Set policy for LLM-generated
+tests](https://github.com/web-platform-tests/rfcs/issues/202) includes evidence
+for public interest in a formal policy for LLM usage in authoring contributions
+to WPT.
+
+The Chrome team is exploring applications of LLMs for detecting coverage gaps
+and for filling those gaps with generated code. ([Project
+repository](https://github.com/GoogleChromeLabs/wpt-gen), [April 2026
+presentation](https://www.youtube.com/watch?v=9r0PBbJFLoM))
+
+A few examples of policies on LLM use in FOSS contributions:
+
+- permissive
+  - [ghostty/AI_POLICY.md at main · ghostty-org/ghostty](https://github.com/ghostty-org/ghostty/blob/main/AI_POLICY.md)
+  - [Policy about LLM generated code from PRs · Issue #28335 · opencv/opencv](https://github.com/opencv/opencv/issues/28335)
+  - [CONTRIBUTING.md: Guidelines relevant to AI-assisted contributions by gasche · Pull Request #14052 · ocaml/ocaml](https://github.com/ocaml/ocaml/pull/14052)
+  - [LLVM AI Tool Use Policy — LLVM 23.0.0git documentation](https://llvm.org/docs/AIToolPolicy.html)
+- prohibitive
+  - [Code of Conduct ⚡ Zig Programming Language](https://ziglang.org/code-of-conduct/#strict-no-llm-no-ai-policy)
+  - [Getting Started - The Servo Book](https://book.servo.org/contributing/getting-started.html#ai-contributions)
+
+## Details
+
+Proposed text:
+
+> ### For Individual Contributors
+>
+> #### Disclosure
+>
+> Contributions that contain substantial amounts of tool-generated content must
+> be labeled as such.
+>
+> #### Attribution
+>
+> Commits generated entirely by an LLM must be attributed to the LLM in the
+> "Author" field.
+>
+> #### Understanding
+>
+> Every pull request must be initiated by one human. That person must author
+> the pull request description, understand every change proposed, and be
+> prepared to engage in technical discussion regarding those changes.
+>
+> ### For Trusted External Review
+>
+> Some external projects conduct review which the WPT maintainers recognize as
+> authoritative. From rendering engines like Gecko to dedicated test suites
+> like WASM, patches merged in these projects are incorporated into WPT without
+> further review. The policy outlined by this document does not apply to these
+> contributions; the external projects are trusted to determine their own
+> mechanisms for quality assurance.
+
+## Risks
+
+### Discouraging volunteers
+
+All but the most permissive policy is effectively another hurdle to
+contributing to the project. Friction in the contribution process could deter
+people who might otherwise volunteer their time to help improve the project.
+
+In some sense, adding friction is the goal of this policy. New technology has
+removed barriers which previously restricted unqualified individuals from
+participation. Rather than introducing more restrictions on good-faith actors,
+an ideal policy will buttress eroded structural barriers with more intentional
+social ones.
+
+### Encouraging low-value contributions
+
+All but the most restrictive policy could be interpreted as an invitation to
+take shortcuts which undermine the quality of contributions.
+
+However, it will not be possible to strictly enforce any policy. It inevitably
+falls on contributors to follow rules and for administrators to police
+transgressions. Respect in public works projects is never guaranteed; policies
+exist only to make expectations clear (this is the same dynamic that guides the
+design and enforcement of codes of conduct).