code: func (f *regularFieldsPrinter) VisitKind(k *proto.Kind) {
  	for _, key := range k.Keys() {
  		v := k.Fields[key]
  		required := ""
  		if k.IsRequired(key) {
  			required = " -required-"
  		}
  
  		if err := f.Writer.Write("%s\t<%s>%s", key, GetTypeName(v), required); err != nil {
  			f.Error = err
  			return
  		}
  		if err := f.Writer.Indent(indentDesc).WriteWrapped("%s", v.GetDescription()); err != nil {
  			f.Error = err
  			return
  		}
  		if err := f.Writer.Write(""); err != nil {
  			f.Error = err
  			return
  		}
  	}
  }
docs: // VisitKind prints a Kind type. It prints each key in the kind, with
  // the type, the required flag, and the description.