def skill_api_method(func):
    """Decorator for adding a method to the skill's public api.
    Methods with this decorator will be registered on the message bus
    and an api object can be created for interaction with the skill.
    """
    # tag the method by adding an api_method member to it
    if not hasattr(func, 'api_method') and hasattr(func, '__name__'):
        func.api_method = True
    return func