make suggested edits

docs/userguide/index.rst

@@ -14,8 +14,8 @@ Transition to PEP517
 ====================
 
 Since setuptools no longer serves as the default build tool, one must explicitly
-opt in (by providing a ``pyproject.toml`` file) to use this library. The user
-facing part is provided by `PEP517 <https://pypi.org/project/pep517/>`_ and
+opt in (by providing a :file:`pyproject.toml` file) to use this library. The user
+facing part is provided by tools such as pip and
 backend interface is described :ref:`in this document <../build_meta>`. The
 quickstart provides an overview of the new workflow.