diff --git a/pkg/api/v1alpha1/actortemplate_types.go b/pkg/api/v1alpha1/actortemplate_types.go
index 5106fb5..c57eefa 100644
--- a/pkg/api/v1alpha1/actortemplate_types.go
+++ b/pkg/api/v1alpha1/actortemplate_types.go
@@ -31,6 +31,8 @@ const (
 )
 
 // A single application container that you want to run within a WorkerPool.
+//
+// +kubebuilder:validation:XValidation:rule="self.image.contains('@')"
 type Container struct {
 	// Name of the container.
 	// +required