[llvm] [docs] Add human-in-the-loop policy for tool-assisted contributions (PR #154441)

[Hubert Tong via llvm-commits]

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+# LLVM AI Tool Use Policy
+
+## Policy
+
+LLVM's policy is that contributors can use whatever tools they would like to
+craft their contributions, but there must be a **human in the loop**.
+**Contributors must read and review all LLM-generated code or text before they
+ask other project members to review it.** The contributor is always the author
+and is fully accountable for their contributions. Contributors should be
+sufficiently confident that the contribution is high enough quality that asking
+for a review is a good use of scarce maintainer time, and they should be **able
+to answer questions about their work** during review.
+
+We expect that new contributors will be less confident in their contributions,
+and our guidance to them is to **start with small contributions** that they can
+fully understand to build confidence. We aspire to be a welcoming community
+that helps new contributors grow their expertise, but learning involves taking
+small steps, getting feedback, and iterating. Passing maintainer feedback to an
+LLM doesn't help anyone grow, and does not sustain our community.
+
+Contributors are expected to **be transparent and label contributions that
+contain substantial amounts of tool-generated content**. Our policy on
+labelling is intended to facilitate reviews, and not to track which parts of
+LLVM are generated. Contributors should note tool usage in their pull request
+description, commit message, or wherever authorship is normally indicated for
+the work. For instance, use a commit message trailer like Assisted-by: <name of
+code assistant>. This transparency helps the community develop best practices
+and understand the role of these new tools.
+
+This policy includes, but is not limited to, the following kinds of
+contributions:
+
+- Code, usually in the form of a pull request
+- RFCs or design proposals
+- Issues or security vulnerabilities
+- Comments and feedback on pull requests
+
+## Details
+
+To ensure sufficient self review and understanding of the work, it is strongly
+recommended that contributors write PR descriptions themselves (if needed,
+using tools for translation or copy-editing). The description should explain
+the motivation, implementation approach, expected impact, and any open
+questions or uncertainties to the same extent as a contribution made without
+tool assistance.
+
+An important implication of this policy is that it bans agents that take action
+in our digital spaces without human approval, such as the GitHub [`@claude`
+agent](https://github.com/claude/). Similarly, automated review tools that
+publish comments without human review are not allowed. However, an opt-in
+review tool that **keeps a human in the loop** is acceptable under this policy.
+As another example, using an LLM to generate documentation, which a contributor
+manually reviews for correctness, edits, and then posts as a PR, is an approved
+use of tools under this policy.
+
+AI tools must not be used to fix GitHub issues labelled [`good first
+issue`][good-first-issue]. These issues are generally not urgent, and are
+intended to be learning opportunities for new contributors to get familiar with
+the codebase. Whether you are a newcomer or not, fully automating the process
+of fixing this issue squanders the learning opportunity and doesn't add much
+value to the project. **Using AI tools to fix issues labelled as "good first
+issues" is forbidden**.
+
+[good-first-issue]: https://github.com/llvm/llvm-project/issues/?q=is%3Aissue%20state%3Aopen%20label%3A%22good%20first%20issue%22
+
----------------
hubert-reinterpretcast wrote:

> @rnk, can you point me to the discussion that led to the inclusion of this paragraph? I have been trying to follow the RFC/RFCs, but I do not recall anything like this.

Sorry, I missed that this was part of the status quo (and merely migrated).

https://github.com/llvm/llvm-project/pull/154441