#10439: document PyCodec C APIs.
diff --git a/Doc/c-api/utilities.rst b/Doc/c-api/utilities.rst
index 6cb4d0d..d4484fb 100644
--- a/Doc/c-api/utilities.rst
+++ b/Doc/c-api/utilities.rst
@@ -18,3 +18,4 @@
    arg.rst
    conversion.rst
    reflection.rst
+   codec.rst