GitHub Copilot Modernization Agent is an AI-powered tool designed to help developers modernize Java and .NET applications efficiently. The GitHub Copilot Modernization CLI provides end-to-end capabilities for analyzing applications, generating modernization plans, and executing tasks in an autonomous manner.
Key Features:
Autonomous workflows for modernizing applications from assessment to execution.
Customizable skills enable organizations to define consistent modernization standards across teams.
Unified command-line interface (CLI) and text-based user interface (TUI) for hands-on application modernization.
Audience & Benefit:
Ideal for developers, architects, and application owners seeking to modernize Java and .NET applications at scale. The tool empowers users to create detailed modernization plans based on natural language prompts, execute tasks with minimal manual intervention, and apply consistent standards across multiple projects. By automating key aspects of the modernization process, it reduces errors, accelerates development, and enhances efficiency.
The GitHub Copilot Modernization Agent can be installed via winget for seamless setup on supported platforms.
README
GitHub Copilot modernization CLI
What is GitHub Copilot modernization CLI?
GitHub Copilot modernization provides AI-powered capabilities to help users modernize Java and .NET applications easily and confidently.
Organizations modernizing multiple applications need consistency, repeatability, and the ability to define standards that apply across every dev team and repository. The GitHub Copilot Modernization Agent is built for these requirements.
Delivered through the Modernize CLI, the modernization agent enables agentic, end-to-end application modernization through intelligent workflow orchestration. It provides architects and app owners with a platform to define modernization standards once - via customizable, reusable skills - and apply them consistently across multiple applications and repositories. It offers a unified CLI and TUI experience for hands-on modernization of individual applications.
GitHub Copilot subscription with Free, Pro, Pro+, Business and Enterprise plans, See Copilot plans.
Installation
Linux / macOS
Option 1 — Homebrew:
brew tap microsoft/modernize https://github.com/microsoft/modernize-cli
brew install modernize
Option 2 — Shell script:
curl -fsSL https://raw.githubusercontent.com/microsoft/modernize-cli/main/scripts/install.sh | sh
The script automatically downloads the latest release, install the modernize bundle to ~/.local/share/modernize, place the modernize command in ~/.local/bin, and add the command directory to your PATH.
After installation, reload your shell profile to apply the PATH update:
Download and run the latest MSI from the Releases page.
All three options place the modernize command in %LOCALAPPDATA%\Programs\modernize and add it to your PATH automatically.
> [!NOTE]
> After installation, open a new terminal for the modernize command to be available on your PATH.
Use the interactive mode
The easiest way to get started is using the interactive mode. First, authenticate with the GitHub CLI:
gh auth login
Then, run the modernization agent:
modernize
You'll be guided through the end-to-end modernization experience via the main menu:
○ How would you like to modernize your Java app?
> 1. Assess application
Analyze the project and identify modernization opportunities
2. Create modernization plan
Generate a structured plan to guide the agent
3. Execute modernization plan
Run the tasks defined in the modernization plan
Commands
Global options
All commands support these global options:
Option
Description
--help, -h
Display help information
--no-tty
Disable interactive prompts (headless mode)
assess
Runs assessment and generates a comprehensive analysis report.
Syntax
modernize assess [options]
Options
Option
Description
Default
--source
Path to source project (relative or absolute local path)
. (current directory)
--output-path
Custom output path for assessment results
.github/modernize/assessment/
--issue-url
GitHub issue URL to update with assessment summary
None
--multi-repo
Enable multi-repo assess. Scans first-level subdirectories for multiple repositories
Disabled
--model
LLM model to use
claude-sonnet-4.6
--delegate
Execution mode: local (this machine) or cloud (Cloud Coding Agent)
local
--wait
Wait for delegated tasks to complete and generate results (only valid with --delegate cloud)
Disabled
--force
Force restart delegation, ignoring ongoing tasks (only valid with --delegate cloud)
We're thrilled to have you join us on the early journey of the modernization agent. Your feedback is invaluable—please share your thoughts with us!
Disclaimer
Unless otherwise permitted under applicable license(s), users may not decompile, modify, repackage, or redistribute any assets, prompts, or internal tools provided as part of this product without prior written consent from Microsoft.