diff --git a/src/gentropy/config.py b/src/gentropy/config.py
index 8f9d63608..ac65c1fe5 100644
--- a/src/gentropy/config.py
+++ b/src/gentropy/config.py
@@ -445,6 +445,11 @@ class _ConsequenceToPathogenicityScoreMap(TypedDict):
         label: str
         score: float
 
+    session: Any = field(
+        default_factory=lambda: {
+            "start_hail": False,
+        }
+    )
     vep_output_json_path: str = MISSING
     variant_index_path: str = MISSING
     gnomad_variant_annotations_path: str | None = None