diff --git a/semantic_router/encoders/mistral.py b/semantic_router/encoders/mistral.py
index b0314284f64582f811a7668a79c66200f79f0b77..20f7f33907ab70f4c1700c72dda5c8e7d1f7ff17 100644
--- a/semantic_router/encoders/mistral.py
+++ b/semantic_router/encoders/mistral.py
@@ -20,7 +20,7 @@ class MistralEncoder(BaseEncoder):
         self,
         name: Optional[str] = None,
         mistral_api_key: Optional[str] = None,
-        score_threshold: Optional[float] = 0.82,
+        score_threshold: float = 0.82,
     ):
         if name is None:
             name = os.getenv("MISTRAL_MODEL_NAME", "mistral-embed")