diff --git a/packages/mistralai_azure/src/mistralai_azure/models/sdkerror.py b/packages/mistralai_azure/src/mistralai_azure/models/sdkerror.py
index 03216cbf..14f7f87e 100644
--- a/packages/mistralai_azure/src/mistralai_azure/models/sdkerror.py
+++ b/packages/mistralai_azure/src/mistralai_azure/models/sdkerror.py
@@ -5,7 +5,7 @@
 import httpx
 
 
-@dataclass
+@dataclass(frozen=True)
 class SDKError(Exception):
     """Represents an error returned by the API."""