diff --git a/gns3server/schemas/controller/appliances.py b/gns3server/schemas/controller/appliances.py
index a4aecaa94..3660067b8 100644
--- a/gns3server/schemas/controller/appliances.py
+++ b/gns3server/schemas/controller/appliances.py
@@ -782,7 +782,7 @@ Appliance = ApplianceUnion
 # Create a validator wrapper for convenience
 from pydantic import TypeAdapter
 
-_appliance_validator = TypeAdapter(ApplianceUnion)
+_appliance_validator: TypeAdapter[Union[ApplianceV1_6, ApplianceV8]] = TypeAdapter(ApplianceUnion)
 
 
 class ApplianceModel:
diff --git a/pyproject.toml b/pyproject.toml
index 7ed8113e2..c4806fbe4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -383,7 +383,6 @@ module = [
   "gns3server.schemas.compute.nat_nodes",  # 1
   "gns3server.schemas.compute.qemu_nodes",  # 1
   "gns3server.schemas.compute.virtualbox_nodes",  # 2
-  "gns3server.schemas.controller.appliances",  # 1
   "gns3server.schemas.controller.computes",  # 6
   "gns3server.schemas.controller.nodes",  # 3
   "gns3server.schemas.controller.projects",  # 2