diff --git a/Doc/c-api/arg.rst b/Doc/c-api/arg.rst
index 35dc01e196e777e..834aae9372fe3bd 100644
--- a/Doc/c-api/arg.rst
+++ b/Doc/c-api/arg.rst
@@ -428,9 +428,7 @@ API Functions
 
       The *keywords* parameter declaration is :c:expr:`char * const *` in C and
       :c:expr:`const char * const *` in C++.
-      This can be overridden by defining the macro :c:macro:`PY_CXX_CONST`
-      before including :file:`Python.h` as ``const`` for the latter and as
-      empty value for the former.
+      This can be overridden with the :c:macro:`PY_CXX_CONST` macro.
 
    .. versionchanged:: 3.6
       Added support for :ref:`positional-only parameters
@@ -516,6 +514,19 @@ API Functions
 
       PyArg_ParseTuple(args, "O|O:ref", &object, &callback)
 
+.. c:macro:: PY_CXX_CONST
+
+   The value to be inserted, if any, before :c:expr:`char * const *`
+   in the *keywords* parameter declaration of
+   :c:func:`PyArg_ParseTupleAndKeywords` and
+   :c:func:`PyArg_VaParseTupleAndKeywords`.
+   Default empty for C and ``const`` for C++
+   (:c:expr:`const char * const *`).
+   To override, define it to the desired value before including
+   :file:`Python.h`.
+
+   .. versionadded:: 3.13
+
 
 ---------------
 Building values
diff --git a/Doc/whatsnew/3.13.rst b/Doc/whatsnew/3.13.rst
index 6127ea7eff0617b..8eede2421c6b7db 100644
--- a/Doc/whatsnew/3.13.rst
+++ b/Doc/whatsnew/3.13.rst
@@ -1107,13 +1107,11 @@ New Features
 * The *keywords* parameter of :c:func:`PyArg_ParseTupleAndKeywords` and
   :c:func:`PyArg_VaParseTupleAndKeywords` has now type :c:expr:`char * const *`
   in C and :c:expr:`const char * const *` in C++, instead of :c:expr:`char **`.
-  It makes these functions compatible with argument of type
+  It makes these functions compatible with arguments of type
   :c:expr:`const char * const *`, :c:expr:`const char **` or
   :c:expr:`char * const *` in C++ and :c:expr:`char * const *` in C
-  without explicit type cast.
-  This can be overridden by defining the macro ``PY_CXX_CONST``
-  before including :file:`Python.h` as ``const`` for the latter and as
-  empty value for the former.
+  without an explicit type cast.
+  This can be overridden with the :c:macro:`PY_CXX_CONST` macro.
   (Contributed by Serhiy Storchaka in :gh:`65210`.)
 
 * Add :c:func:`PyImport_AddModuleRef`: similar to