It might be experimental

doc/python/sphinx/glossary.rst

@@ -42,8 +42,8 @@ Glossary
 
   channel_arguments
     A list of key-value pairs to configure the underlying gRPC Core channel or
-    server object. Channel arguments are meant for advanced usages. Full list
-    channel arguments can be found under the "grpc_arg_keys" section of
-    "grpc_types.h" header file (|grpc_types_link|). For example, if you want to
-    disable TCP port reuse, you may construct channel arguments like: ``options
-    = (('grpc.so_reuseport', 0),)``.
+    server object. Channel arguments are meant for advanced usages and contain
+    experimental API. Full list channel arguments can be found under the
+    "grpc_arg_keys" section of "grpc_types.h" header file (|grpc_types_link|).
+    For example, if you want to disable TCP port reuse, you may construct
+    channel arguments like: ``options = (('grpc.so_reuseport', 0),)``.