def METHOD_NAME(key, value, endpoint=None):
    """ This is binary annotation API.
    You can add your own key-value extra information from in your code.
    Key-value doesn't have a time component.
    e.g.) put_key_value('http.uri', '/hoge/index.html')
    :param key: String
    :param value: String
    :param endpoint: host info
    """
    if is_sample():
        b = ZipkinDataBuilder.build_binary_annotation(key, value, endpoint)
        trace_data = get_trace_data()
        trace_data.add_binary_annotation(b)