The dir() listing omits the attributes "description" and "phrase": >>> import http >>> from pprint import pp >>> r = http.HTTPStatus(404) >>> pp(vars(r)) {'_value_': 404, 'phrase': 'Not Found', 'description': 'Nothing matches the given URI', '_name_': 'NOT_FOUND', '__objclass__': <enum 'HTTPStatus'>} >>> r.value 404 >>> r.name 'NOT_FOUND' >>> r.description 'Nothing matches the given URI' >>> r.phrase 'Not Found' >>> dir(r) ['__class__', '__doc__', '__module__', 'as_integer_ratio', 'bit_length', 'conjugate', 'denominator', 'from_bytes', 'imag', 'name', 'numerator', 'real', 'to_bytes', 'value'] One fix would be to teach IntEnum.__dir__() to include entries in the instance dict. Another fix would be to provide a way for a IntEnum subclass to add to the known members list.

Adding to the existing dir() is as easy as writing one's own __dir__. I think using the instance dict and omitting any keys with a leading underscore will do the right thing most of the time. The fix should into `Enum` and not just `IntEnum` as other enumerations could also have extra attributes.

 New changeset 68526fe258da8c01196fd7cf48e8e5f1280bf8fd by Angelin BOOZ in branch 'master': bpo-40084: Enum - dir() includes member attributes (GH-19219) https://github.com/python/cpython/commit/68526fe258da8c01196fd7cf48e8e5f1280bf8fd 

 New changeset f6d1520219899874d78e7710934c9b21af880f9a by Miss Islington (bot) in branch '3.8': bpo-40084: [Enum] dir() includes member attributes (GH-19219) (GH-22853) https://github.com/python/cpython/commit/f6d1520219899874d78e7710934c9b21af880f9a 

 New changeset 33cbb04986d0dabb9c542edc52bb4ea6106d3a81 by Miss Islington (bot) in branch '3.9': bpo-40084: Enum - dir() includes member attributes (GH-19219) https://github.com/python/cpython/commit/33cbb04986d0dabb9c542edc52bb4ea6106d3a81