diff --git a/homeassistant/components/launch_library/sensor.py b/homeassistant/components/launch_library/sensor.py
index 4deb444f929..470c2e678cf 100644
--- a/homeassistant/components/launch_library/sensor.py
+++ b/homeassistant/components/launch_library/sensor.py
@@ -32,21 +32,14 @@ from .const import DOMAIN
 DEFAULT_NEXT_LAUNCH_NAME = "Next launch"
 
 
-@dataclass(frozen=True)
-class LaunchLibrarySensorEntityDescriptionMixin:
-    """Mixin for required keys."""
+@dataclass(frozen=True, kw_only=True)
+class LaunchLibrarySensorEntityDescription(SensorEntityDescription):
+    """Describes a Next Launch sensor entity."""
 
     value_fn: Callable[[Launch | Event], datetime | int | str | None]
     attributes_fn: Callable[[Launch | Event], dict[str, Any] | None]
 
 
-@dataclass(frozen=True)
-class LaunchLibrarySensorEntityDescription(
-    SensorEntityDescription, LaunchLibrarySensorEntityDescriptionMixin
-):
-    """Describes a Next Launch sensor entity."""
-
-
 SENSOR_DESCRIPTIONS: tuple[LaunchLibrarySensorEntityDescription, ...] = (
     LaunchLibrarySensorEntityDescription(
         key="next_launch",