diff --git a/src/PluginManagerInterface.php b/src/PluginManagerInterface.php
index 483dece7..ed04d137 100644
--- a/src/PluginManagerInterface.php
+++ b/src/PluginManagerInterface.php
@@ -29,7 +29,7 @@ public function validate(mixed $instance): void;
     /**
      * @template TRequestedInstance extends InstanceType
      * @psalm-param class-string<TRequestedInstance>|string $id Service name of plugin to retrieve.
-     * @psalm-return ($id is class-string ? TRequestedInstance : InstanceType)
+     * @psalm-return ($id is class-string<TRequestedInstance> ? TRequestedInstance : InstanceType)
      * @throws Exception\ServiceNotFoundException If the manager does not have
      *     a service definition for the instance, and the service is not
      *     auto-invokable.
@@ -43,7 +43,7 @@ public function get(string $id): mixed;
      *
      * @template TRequestedInstance extends InstanceType
      * @psalm-param string|class-string<TRequestedInstance> $name
-     * @psalm-return ($name is class-string ? TRequestedInstance : InstanceType)
+     * @psalm-return ($name is class-string<TRequestedInstance> ? TRequestedInstance : InstanceType)
      * @throws Exception\ServiceNotFoundException If no factory/abstract
      *     factory could be found to create the instance.
      * @throws Exception\ServiceNotCreatedException If factory/delegator fails