diff --git a/core/configure/proto/multi_lang_general_model_service.proto b/core/configure/proto/multi_lang_general_model_service.proto
index ec1ee3a247e9b9d87c55a8997e9fb1013844cb2d..fc6ac80517e8865d321226816caff2a916033e60 100644
--- a/core/configure/proto/multi_lang_general_model_service.proto
+++ b/core/configure/proto/multi_lang_general_model_service.proto
@@ -15,7 +15,7 @@
 syntax = "proto2";
 
 message Tensor {
-  repeated bytes data = 1;
+  optional bytes data = 1;
   repeated int32 int_data = 2;
   repeated int64 int64_data = 3;
   repeated float float_data = 4;
@@ -32,6 +32,7 @@ message Request {
   repeated FeedInst insts = 1;
   repeated string feed_var_names = 2;
   repeated string fetch_var_names = 3;
+  required bool is_python = 4 [ default = true ];
 };
 
 message Response {