diff --git a/proto/sagittarius/sagittarius.module.proto b/proto/sagittarius/sagittarius.module.proto
index 8ae3f2f..4bc32a7 100644
--- a/proto/sagittarius/sagittarius.module.proto
+++ b/proto/sagittarius/sagittarius.module.proto
@@ -11,6 +11,9 @@ import "shared.module.proto";
 message ModuleUpdateRequest {
   // List of modules
   repeated shared.Module modules = 1;
+
+  // List of all available definition sources
+  repeated string available_defintition_soruces = 2;
 }
 
 // Response of updating modules including data types, flow types and runtime function definitions
diff --git a/proto/shared/shared.module.proto b/proto/shared/shared.module.proto
index 0e0ab79..ebde68e 100644
--- a/proto/shared/shared.module.proto
+++ b/proto/shared/shared.module.proto
@@ -29,6 +29,8 @@ message Module {
 
   repeated ModuleConfigurationDefinition configurations = 14;
   repeated ModuleDefinition definitions = 15;
+
+  string definition_source = 16;
 }
 
 message ModuleDefinition {