Confused by the lack of class and __init__ docs from autoclass with :members:

[djc]

I'm working on a project using PyO3 to build a Python library in Rust. For this project I'd like to generate good reference documentation directly from the docstrings embedded in the Rust code. As such, I set up reST code like this:

.. autoclass:: ClientConfig
   :members:

This gets me nicely documented methods for the type, but it seems that a docstring attached to a type itself (which does show up when using help(ClientConfig) in the REPL) does not make it into the generated docs. Am I missing something here?