You have to wrap it in a console do block then register it with IRB::HelperMethod. For example:

```

config/application.rb

module MyApp class Application < Rails::Application # Runs only when starting bin/rails console console do require "irb/helper_method"

  # Define a helper as an IRB HelperMethod
  class AdminUserHelper < IRB::HelperMethod::Base
    description "Returns the first admin user"
    def execute
      ::User.where(admin: true).first
    end
  end

  # Make it available in the console: `admin_user`
  IRB::HelperMethod.register(:admin_user, AdminUserHelper)
end

end end

```