def METHOD_NAME(self, keys: Optional[List[str]] = None, **kwargs) -> str:
    """
    Load conversation history as a formatted string, including the latest summary.
    :param keys: Optional list of keys (ignored in this implementation).
    :param kwargs: Optional keyword arguments
        - window_size: integer specifying the number of most recent conversation snippets to load.
    :return: A formatted string containing the conversation history with the latest summary.
    """
    if self.has_unsummarized_snippets():
        unsummarized = self.load_recent_snippets(window_size=self.unsummarized_snippets())
        return f"{self.summary}\n{unsummarized}"
    else:
        return self.summary