pydocstyle is a static analysis tool for checking compliance with Python docstring conventions. pydocstyle supports most of PEP 257 out of the box, but it should not be considered a reference implementation. The framework for checking docstring style is flexible, and custom checks can be easily added, for example to cover NumPy docstring conventions. pydocstyle supports Python 2.6, 2.7, 3.3, 3.4, 3.5, pypy and pypy3.