diff --git a/LICENCE b/LICENCE
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@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Ville Saukkonen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
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diff --git a/README.md b/README.md
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+++ b/README.md
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-# OpenAI code reviewer
+# AI Code Reviewer
 
-This action uses OpenAI apis to review the code you write.
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+AI Code Reviewer is a GitHub Action that leverages OpenAI's GPT-4 API to provide intelligent feedback and suggestions on your pull requests. This powerful tool helps improve code quality and saves developers time by automating the code review process.
+
+## Features
+
+- Reviews pull requests using OpenAI's GPT-4 API.
+- Provides intelligent comments and suggestions for improving your code.
+- Filters out files that match specified exclude patterns.
+- Easy to set up and integrate into your GitHub workflow.
+
+## Setup
+
+1. To use this GitHub Action, you need an OpenAI API key. If you don't have one, sign up for an API key at [OpenAI](https://beta.openai.com/signup).
+
+2. Add the OpenAI API key as a GitHub Secret in your repository with the name `OPENAI_API_KEY`. You can find more information about GitHub Secrets [here](https://docs.github.com/en/actions/reference/encrypted-secrets).
+
+3. The `GITHUB_TOKEN` is automatically made available to the actions environment by GitHub. However, if you need additional permissions or you want to use the action in a private repository, you might need to create a Personal Access Token (PAT) with the appropriate permissions. You can find more information about creating a PAT [here](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/creating-a-personal-access-token). If you create a PAT, add it as a GitHub Secret in your repository with the name `USER_GITHUB_TOKEN`.
+
+4. Create a `.github/workflows/main.yml` file in your repository and add the following content:
+
+```yaml
+name: AI Code Reviewer
+
+on:
+  pull_request:
+    types:
+      - opened
+      - synchronize
+
+jobs:
+  review:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repo
+        uses: actions/checkout@v2
+
+      - name: AI Code Reviewer
+        uses: your-username/ai-code-reviewer@main
+        with:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} # Replace with secrets.USER_GITHUB_TOKEN if using a PAT
+          OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
+          exclude: "**/*.json, **/*.md" # Optional: exclude patterns separated by commas
+```
+
+5. Replace `your-username` with your GitHub username or organization name where the AI Code Reviewer repository is located.
+
+6. Customize the `exclude` input if you want to ignore certain file patterns from being reviewed.
+
+7. Commit the changes to your repository, and AI Code Reviewer will start working on your future pull requests.
+
+## How It Works
+
+The AI Code Reviewer GitHub Action retrieves the pull request diff, filters out excluded files, and sends code chunks to the OpenAI API. It then generates review comments based on the AI's response and adds them to the pull request.
+
+## Contributing
+
+Contributions are welcome! Please feel free to submit issues or pull requests to improve the AI Code Reviewer GitHub Action.
+
+## License
+
+This project is licensed under the MIT License. See the [LICENSE](LICENSE) file for more information.