diff --git a/pkg/apis/core/types.go b/pkg/apis/core/types.go
index 46058c92cfe..d13429a0df1 100644
--- a/pkg/apis/core/types.go
+++ b/pkg/apis/core/types.go
@@ -2599,6 +2599,7 @@ type PodSpec struct {
 	RuntimeClassName *string
 	// EnableServiceLinks indicates whether information about services should be injected into pod's
 	// environment variables, matching the syntax of Docker links.
+	// If not specified, the default is true.
 	// +optional
 	EnableServiceLinks *bool
 }