This is a command line tool for Just D. You can see the documentation at here.
You need to do this in your new project directory. And make sure you have installed Tailwind CSS and React.
npx just-cli@latest init
After that, you can run the following command to start adding new components.
npx just-cli@latest add <component-name>
npx just-cli@latest diff
It will show you the difference between the current and the new component. And it will also ask you to confirm the changes.