Gradle - Can't access class fields

I am creating a gradle plugin in groovy, but I can't access the fields of the class. Here's what I have:

public class MyPlugin implements Plugin<Project> {
  void apply(Project project) {
     project.extensions.create("myClass", MyClass)
     ....
     println project.myClass.getClass().getName()
     ....
     println field.getName()
     println field.getType()
     ...         
  }
}

class MyClass {
  @MyAnnotation("Hello world")
  String myFeild
}

Output

MyClass_Decorated
__$stMC
boolean

Expected

MyClass
myField
String