How can cake build arguments be documented?

In a cake build script there is a very neat way of documenting the tasks using the .Description() extension on the Task. These descriptions are displayed when calling the build script with the -showdescription argument.

I have several custom arguments in my build script that I'd like to document somehow. Currently I added a task that outputs a description text similar to the manual page style for the available arguments that looks something like this:

var nextLineDescription = "\n\t\t\t\t\t"; // for formatting 
Console.WriteLine("ARGUMENTS");
Console.WriteLine("");

Console.WriteLine("\t--someparameter=<number>\t\t" +
                "Description of the parameter" + nextLineDescription +
                "that can span multiple lines" + nextLineDescription +
                "and defaults to 5.\n");

This works fine but is a lot of work, especially if the text should be properly formatted so it's readable in the command line.

So when I call ./build.ps1 -Target MyDocTask I get a nice result:

ARGUMENTS

        --someparameter=number          Description of the parameter
                                        that can span multiple lines
                                        and defaults to 5

        --nextParameter                 Next description

...

Is there another way or a best practice to add documentation for arguments so it can be displayed in the command line similar to the tasks descriptions?

Edit: Alternatively, can I find all available parameters in my build script to loop over them and generate such a description instead of writing it manually for each parameter?