AI-powered tools for upgrading and modernizing .NET applications, available as a Copilot CLI plugin and as a Copilot Coding Agent custom agent.

The modernize-dotnet plugin adds an AI agent to Copilot CLI that guides you through upgrading .NET Framework and .NET applications to the latest versions of .NET.

1. Add the marketplace:

   /plugin marketplace add dotnet/modernize-dotnet
   

2. Install the plugin:

   /plugin install modernize-dotnet@modernize-dotnet-plugins
   

3. Use the agent — see the plugin README for usage details.

Note: You may need to restart Copilot CLI after installing the plugin before the agent becomes available (tracking issue).

A custom agent definition and setup steps are provided for use with Copilot Coding Agent in GitHub. This allows Copilot to modernize .NET projects directly via pull requests.

See the coding-agent README for setup instructions.

├── .github/plugin/marketplace.json   # Plugin marketplace definition
├── plugins/modernize-dotnet/         # Copilot CLI plugin
└── coding-agent/                     # Copilot Coding Agent setup

The previous contents of this repository have been archived to the following branches:

• archive/oldua — original Upgrade Assistant (last updated January 2024)
• archive/mappings — API mappings data (last updated December 2024)