diff --git a/lib/private/AppFramework/Utility/SimpleContainer.php b/lib/private/AppFramework/Utility/SimpleContainer.php
index 2aa5da116e..84c4c3447a 100644
--- a/lib/private/AppFramework/Utility/SimpleContainer.php
+++ b/lib/private/AppFramework/Utility/SimpleContainer.php
@@ -52,11 +52,11 @@ class SimpleContainer implements ArrayAccess, ContainerInterface, IContainer {
 		$this->container = new Container();
 	}
 
-	public function get($id) {
+	public function get(string $id) {
 		return $this->query($id);
 	}
 
-	public function has($id): bool {
+	public function has(string $id): bool {
 		// If a service is no registered but is an existing class, we can probably load it
 		return isset($this->container[$id]) || class_exists($id);
 	}