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CONTRIBUTING.md

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+# Contributing
+
+We are grateful you have decided to contribute to the CivMC repository and become part of the over 14-year history
+that is Civ. There are a few things you should know before making your first contribution.
+
+We would greatly appreicate if you tested your changes, ideally using the Docker setup in this repository using
+`docker compose up paper proxy -d`. This will start up a single server on localhost.
+
+Keep in mind that if you are making any config changes, you should change the default plugin config in the resources
+folder, but also update the configs for the relevant server(s) if necessary. `gamma` is the code name for CivMC mini,
+and most changes applied to main should also apply to mini. You can find these configs in `ansible/files`.
+
+Default config changes will not affect the docker server, but ansible changes will. If you make any config changes in
+the `ansible` directory, simply restart the server `docker compose restart paper` to apply them.
+
+If you make any code changes, run `./gradlew build` and then restart the server.
+
+## Submitting a PR
+
+Please attempt to keep your changesets minimal and easy to review: don't create a massive diff or change anything
+out of scope - unless there is some obvious benefit - without calling out why.
+
+In your description, you should list a summary of your changes and *why* you have made those changes. This helps put
+it in context for us to review.
+
+**Important:** We have a strict LLM disclosure policy. Please disclose whether you used LLMs and which model you used
+in your PR description. Failure to do this will cause your PR to be closed and you to be blocked from contributing
+to the repository.