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+# FCP Mod Updater
+
+A command-line tool for managing [Fallout Collaboration Project](https://github.com/FalloutCollaborationProject) RimWorld mods. Features both interactive and automated workflows for discovering, updating, installing, and managing FCP mods.
+
+## Features
+
+- **Auto-discover** RimWorld installation across Steam, GOG, and Lutris on Windows, Linux, and macOS
+- **Interactive mode** with rich terminal UI for browsing, updating, and managing mods
+- **Batch update mode** for automation scripts
+- **Install new mods** directly from the FCP GitHub organization
+- **Convert local mods** (ZIP downloads) to Git repositories for easy updates
+- **Branch/commit switching** for testing specific mod versions
+- **Status overview** showing update availability, local changes, and sync state
+
+## Requirements
+
+- [.NET 10.0 Runtime](https://dotnet.microsoft.com/download) or later (Except for Self-Contained Releases)
+- [Git](https://git-scm.com/downloads) installed and available in PATH
+
+## Installation
+
+### Pre-Compiled Releases
+Releases will be uploaded to the releases tab periodically, versions suffixed with selfcontained don't require .NET 10 to be installed, 
+while other versions are smaller in size but do require .NET 10.
+
+### Build from Source
+```bash
+git clone https://github.com/FalloutCollaborationProject/FCPModUpdater.git
+cd FCPModUpdater
+dotnet build
+```
+
+## Usage
+
+### Interactive Mode (Default)
+
+```bash
+dotnet run -- scan
+```
+
+Launches the interactive menu where you can:
+- View status of all installed FCP mods
+- Update mods with available changes
+- Install new mods from FCP
+- Uninstall mods
+- Convert local (non-git) mods to git repositories
+- Switch mod versions (branches/commits)
+
+### Batch Update Mode
+
+```bash
+dotnet run -- update
+```
+
+Non-interactive mode that updates all FCP mods with available changes. Ideal for automation and scheduled tasks. Returns exit code 0 on success, 1 if any updates fail.
+
+### Options
+
+Both commands accept:
+- `-d, --directory <path>` — Path to RimWorld Mods folder (auto-discovers if omitted)
+
+```bash
+dotnet run -- scan --directory "/path/to/RimWorld/Mods"
+dotnet run -- update -d "C:\Games\RimWorld\Mods"
+```
+
+## Environment Variables
+
+| Variable | Description |
+|----------|-------------|
+| `GITHUB_TOKEN` | Optional. GitHub personal access token to increase API rate limit from 60 to 5000 requests/hour |
+
+## How Mods Are Identified
+
+FCP mods are identified by:
+1. Git remote URL containing `github.com/FalloutCollaborationProject/`
+2. Folder name matching an FCP repository (supports ZIP downloads with branch suffixes like `-main`)
+
+Only repositories tagged with the `rimworld-mod` topic are included.
+
+## Status Icons
+
+| Icon | Status | Description |
+|------|--------|-------------|
+| ✓ | Up to Date | No updates available |
+| ↓ | Behind | Updates available |
+| ↑ | Ahead | Local commits not on remote |
+| ⇅ | Diverged | Both behind and ahead |
+| ~ | Modified | Has uncommitted local changes |
+| — | Not Git | Local folder (not a git repo) |
+| ✗ | Error | Git operation failed |