diff --git a/src/llm/migrations/0005_update_llm_models_to_zdr_current.py b/src/llm/migrations/0005_update_llm_models_to_zdr_current.py
index c54b19a..3d1d5ce 100644
--- a/src/llm/migrations/0005_update_llm_models_to_zdr_current.py
+++ b/src/llm/migrations/0005_update_llm_models_to_zdr_current.py
@@ -47,7 +47,7 @@
 
 # Best-effort inverse for rollback. Many-to-one mappings collapse to the
 # first/representative source model.
-REVERSE_MAPPING = {}
+REVERSE_MAPPING: dict[str, str] = {}
 for _old, _new in MODEL_MAPPING.items():
     REVERSE_MAPPING.setdefault(_new, _old)