diff --git a/packages/proto-loader/bin/proto-loader-gen-types.ts b/packages/proto-loader/bin/proto-loader-gen-types.ts
index 04717f3fb..82a13a123 100644
--- a/packages/proto-loader/bin/proto-loader-gen-types.ts
+++ b/packages/proto-loader/bin/proto-loader-gen-types.ts
@@ -542,7 +542,7 @@ function generateServiceHandlerInterface(formatter: TextFormatter, serviceType:
 }
 
 function generateServiceDefinitionInterface(formatter: TextFormatter, serviceType: Protobuf.Service) {
-  formatter.writeLine(`export interface ${serviceType.name}Definition {`);
+  formatter.writeLine(`export interface ${serviceType.name}Definition extends grpc.ServiceDefinition {`);
   formatter.indent();
   for (const methodName of Object.keys(serviceType.methods).sort()) {
     const method = serviceType.methods[methodName];
diff --git a/packages/proto-loader/golden-generated/google/longrunning/Operations.ts b/packages/proto-loader/golden-generated/google/longrunning/Operations.ts
index 8e5684ada..7644f974d 100644
--- a/packages/proto-loader/golden-generated/google/longrunning/Operations.ts
+++ b/packages/proto-loader/golden-generated/google/longrunning/Operations.ts
@@ -232,7 +232,7 @@ export interface OperationsHandlers extends grpc.UntypedServiceImplementation {
   
 }
 
-export interface OperationsDefinition {
+export interface OperationsDefinition extends grpc.ServiceDefinition {
   CancelOperation: MethodDefinition<_google_longrunning_CancelOperationRequest, _google_protobuf_Empty, _google_longrunning_CancelOperationRequest__Output, _google_protobuf_Empty__Output>
   DeleteOperation: MethodDefinition<_google_longrunning_DeleteOperationRequest, _google_protobuf_Empty, _google_longrunning_DeleteOperationRequest__Output, _google_protobuf_Empty__Output>
   GetOperation: MethodDefinition<_google_longrunning_GetOperationRequest, _google_longrunning_Operation, _google_longrunning_GetOperationRequest__Output, _google_longrunning_Operation__Output>
diff --git a/packages/proto-loader/golden-generated/google/showcase/v1beta1/Echo.ts b/packages/proto-loader/golden-generated/google/showcase/v1beta1/Echo.ts
index acb911270..8e75c6c1a 100644
--- a/packages/proto-loader/golden-generated/google/showcase/v1beta1/Echo.ts
+++ b/packages/proto-loader/golden-generated/google/showcase/v1beta1/Echo.ts
@@ -191,7 +191,7 @@ export interface EchoHandlers extends grpc.UntypedServiceImplementation {
   
 }
 
-export interface EchoDefinition {
+export interface EchoDefinition extends grpc.ServiceDefinition {
   Block: MethodDefinition<_google_showcase_v1beta1_BlockRequest, _google_showcase_v1beta1_BlockResponse, _google_showcase_v1beta1_BlockRequest__Output, _google_showcase_v1beta1_BlockResponse__Output>
   Chat: MethodDefinition<_google_showcase_v1beta1_EchoRequest, _google_showcase_v1beta1_EchoResponse, _google_showcase_v1beta1_EchoRequest__Output, _google_showcase_v1beta1_EchoResponse__Output>
   Collect: MethodDefinition<_google_showcase_v1beta1_EchoRequest, _google_showcase_v1beta1_EchoResponse, _google_showcase_v1beta1_EchoRequest__Output, _google_showcase_v1beta1_EchoResponse__Output>