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+# System
+.DS_Store
+__pycache__ 
+
+# Brewfile
 Brewfile
-Brewfile_*.backup
-.DS_Store
\ No newline at end of file
+Brewfile_*.backup
\ No newline at end of file
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+# Brewfile Tool
+
+A tool to manage Homebrew packages from a CSV file.
+
+## Features
+
+- Generate a Brewfile from a CSV list of packages.
+- Install packages via the Brewfile, automatically resolving required dependencies.
+- Check installation status and clean up packages not listed in the Brewfile.
+
+## Requirements
+
+- macOS
+- [Homebrew](https://brew.sh)
+- Python 3
+
+## CSV Format
+
+Packages are defined in `apps.csv`. Each row describes one package.
+
+![csv_edit](/assets/csv_edit.png)
+
+### Columns
+
+| Column           | Required | Type   | Description                                                  |
+| ---------------- | -------- | ------ | ------------------------------------------------------------ |
+| name             | Yes      | string | Exact package name used by the installer.                    |
+| type             | Yes      | enum   | One of `formula`, `cask`, `mas`, `vscode`, or `manual`.      |
+| mas_id           | No       | string | Mac App Store app ID. Required only when `type` is `mas`.    |
+| install_on_setup | Yes      | bool   | `yes` to include the package in the Brewfile, otherwise `no`.|
+| description      | No       | string | Short note about the package, written as a Brewfile comment. |
+
+* Rows with a `type` of `manual` are ignored during generation.
+Thus, setting `install_on_setup` with `manual` type doesn't have any effect.
+
+* This tool only reads and uses 5 columns stated in this table.
+It is free to make more columns to add more metadata for packages.
+
+
+### Types
+
+| Type    | Brewfile Entry            | Dependency                    |
+| ------- | ------------------------- | ----------------------------- |
+| formula | `brew "..."`              | none                          |
+| cask    | `cask "..."`              | none                          |
+| mas     | `mas "...", id: ...`      | `mas` (install if missing)  |
+| vscode  | `vscode "..."`            | `code` (install if missing) |
+
+## Usage
+
+Run the tool and select an option from the menu.
+
+```
+python3 brewfile_tool.py
+
+╰─➤ Select option
+     1) Create Brewfile
+     2) Install packages
+     3) Check packages
+     4) Cleanup packages
+     5) Exit
+    option: 
+```
+
+| Option          | Description                                                          |
+| --------------- | ------------------------------------------------------------------- |
+| Create Brewfile | Generate a Brewfile from `apps.csv`. The old Brewfile is automatically backed up. |
+| Install packages| Install dependencies if needed, then run `brew bundle install`.     |
+| Check packages  | Verify that every package in the Brewfile is installed.             |
+| Cleanup packages| Remove installed packages that are not listed in the Brewfile.      |
+| Exit            | Quit the tool.                                                      |
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