package main import ( "github.com/cloudfoundry/cli/cf" "github.com/cloudfoundry/cli/cf/command_registry" "github.com/cloudfoundry/cli/plugin" ) func main() { app := cf.NewApp() app.Name = "myapp" app.Usage = "A simple CLI app" app.Version = "0.0.1" plugin.Start(&plugin.Plugin{ Commands: []plugin.Command{ { Name: "hello", HelpText: "Prints hello world", Alias: "h", UsageDetails: plugin.Usage{ Usage: "cf hello", }, Command: func(args []string) { // Command implementation here fmt.Println("Hello world!") }, }, }, }) command_registry.Commands().Register(app.Commands...) // Run the CLI app cf.RunApp(app) }In this example, we are registering a new command called "hello" using the `plugin.Command` struct provided by the `github.com/cloudfoundry/cli/plugin` package. We then register this command (as well as any other commands defined by the `app.Commands` slice) with the `github.com.cloudfoundry.cli.cf.command_registry` package using the `command_registry.Commands().Register()` method. Package library: `github.com.cloudfoundry.cli.cf.command_registry`.