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+# AGENTS.md
+
+Guidelines for AI agents working in this repository.
+
+## Branch rules
+- Never commit directly to `main`.
+- Always work on a feature branch.
+- If the current branch is `main`, stop and ask the user to create a branch.
+
+## Development workflow
+Before committing:
+1. Run `pre-commit run --all-files`
+2. Run `pytest`
+
+Do not bypass pre-commit hooks.
+
+## Scope of changes
+- Only modify files necessary for the requested task.
+- Do not refactor unrelated code.
+- Do not change project structure unless explicitly asked.
+- Make the minimal change required to solve the requested task.
+- If the task expands beyond the original request, stop and ask the user for guidance.
+
+## Dependencies
+If tests fail due to missing dependencies, install them rather than skipping tests.
+
+## CI
+Do not modify GitHub CI workflows unless explicitly asked.
+
+## Documentation
+If implementation behavior changes, update the specification documents to match.