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+# AI policy
+
+## 1. Introduction
+
+1.1. Physlib generally welcomes AI-assisted contributions.
+
+1.2. If you use an AI tool to help author a pull request to Physlib, you must follow the guidelines in this file.
+
+1.3. Failure to follow these guidelines may result in your PR being closed without comment after a brief triage. Repeated failures may result in being banned from contributing to the project. This is to protect the project and the time of the maintainers.
+
+1.4. Throughout this document, "must" denotes a hard requirement and "should" denotes a strong expectation that is not strictly enforced.
+
+1.5. You must also follow any explicit instructions in [docs/ReviewGuidelines.md](docs/ReviewGuidelines.md).
+
+1.6. These guidelines apply to any contribution where an AI tool produced more than trivial assistance.
+
+1.7. The human author is fully responsible for every line of the PR.
+
+## 2. Rules for the content of PRs
+
+2.1. `theorem` must only be used for well-known results in the physics literature; otherwise `lemma` must be used.
+
+2.2. Added results must be placed in sections with appropriate titles. Sections must be numbered using the scheme `# A. ...`, `## A.1. ...`, etc. See [Physlib/ClassicalMechanics/HarmonicOscillator/Basic.lean](Physlib/ClassicalMechanics/HarmonicOscillator/Basic.lean) for an example.
+
+2.3. Results must be placed in the appropriate file, with the existing library structure in mind. Do not introduce new files without good reason.
+
+2.4. Long proofs (over 50 LoC) should, where sensible, be split into smaller lemmas of general applicability.
+
+2.5. New lemmas must not be trivial rewrites of existing lemmas in Mathlib or Physlib, unless they add new or different physics context.
+
+2.6. All content must pass the linters described in [scripts/README.md](scripts/README.md).
+
+2.7. Contributions must not contain `axiom` declarations. ch.
+
+2.8. Any bibliographic references included must be verified by a human for correctness (existence of the work, accuracy of the cited statement, page numbers, etc.).
+
+## 3. Rules for the structure of the PR
+
+3.1. A pull request that adds new content (as opposed to refactoring existing content) should contain less than 250 lines of diff. Split larger contributions into multiple PRs.
+
+3.2. PRs should be split into atomic commits where it makes sense.
+
+3.3. Commit titles must describe the lemmas or definitions added or changed.
+
+3.4. PRs must be focused and have well-defined scope.
+
+## 4. Rules for the PR description
+
+4.1. The PR description must list all lemmas and definitions added or removed, the file in which each appears, and a brief explanation of each.
+
+4.2. The PR description should include a reviewer map: a brief guide indicating the order in which the reviewer should look at the changes.
+
+4.3. The PR description should state the author's expertise in the area of the PR.
+
+4.4. The PR description must disclose that an AI was used and describe the extent of its involvement.
+
+4.5. The PR description must state whether a human has checked the correctness of any included references.
+
+4.6. The PR must be concise.
+
+## 5. Rules for the review process
+
+5.1. All communication with human reviewers must be conducted by humans, not by an AI agent.
+
+5.2. If an AI agent is used to implement reviewer feedback, the author must independently verify that the feedback has been addressed correctly before requesting re-review. This must not be left to the reviewer to check.