--- /dev/null
+<?php
+
+namespace Drupal\entity_test\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Constraint on entity entity level.
+ *
+ * @Constraint(
+ * id = "EntityTestEntityLevel",
+ * label = @Translation("Constraint on the entity level."),
+ * type = "entity"
+ * )
+ */
+class EntityTestEntityLevel extends Constraint {
+
+ public $message = 'Entity level validation';
+
+}