diff --git a/google/cloud/dataproc/v1beta2/clusters.proto b/google/cloud/dataproc/v1beta2/clusters.proto
index 0b277e2393..2e9e648c5a 100644
--- a/google/cloud/dataproc/v1beta2/clusters.proto
+++ b/google/cloud/dataproc/v1beta2/clusters.proto
@@ -104,7 +104,7 @@ service ClusterController {
   // After the operation completes,
   // [Operation.response][google.longrunning.Operation.response]
   // contains
-  // [Empty](google.protobuf.Empty).
+  // [Empty][google.protobuf.Empty].
   rpc DiagnoseCluster(DiagnoseClusterRequest) returns (google.longrunning.Operation) {
     option (google.api.http) = {
       post: "/v1beta2/projects/{project_id}/regions/{region}/clusters/{cluster_name}:diagnose"