diff --git a/src/ContainerInterface.php b/src/ContainerInterface.php
index b2cad40..fdc1c08 100644
--- a/src/ContainerInterface.php
+++ b/src/ContainerInterface.php
@@ -12,12 +12,14 @@ interface ContainerInterface
     /**
      * Finds an entry of the container by its identifier and returns it.
      *
-     * @param string $id Identifier of the entry to look for.
+     * @template T of object
+     *
+     * @param class-string<T>|string $id Identifier of the entry to look for.
      *
      * @throws NotFoundExceptionInterface  No entry was found for **this** identifier.
      * @throws ContainerExceptionInterface Error while retrieving the entry.
      *
-     * @return mixed Entry.
+     * @return ($id is class-string<T> ? T : mixed) Entry.
      */
     public function get(string $id);