diff --git a/api/routes/smart_assistant.py b/api/routes/smart_assistant.py
index 1671c1c..29f0201 100644
--- a/api/routes/smart_assistant.py
+++ b/api/routes/smart_assistant.py
@@ -27,6 +27,11 @@ def _verify_auth(request: Request):
         return  # No auth configured
     provided = request.headers.get("X-Api-Key", "")
     if provided != expected:
+        logger.warning(
+            "[auth] Key mismatch — expected=%s... provided=%s...",
+            expected[:8] if expected else "NONE",
+            provided[:8] if provided else "NONE",
+        )
         raise HTTPException(status_code=401, detail="Unauthorized")