diff --git a/ragna/assistants/_ollama.py b/ragna/assistants/_ollama.py
index 4c2313f3..a9de8119 100644
--- a/ragna/assistants/_ollama.py
+++ b/ragna/assistants/_ollama.py
@@ -56,7 +56,8 @@ async def _call_api(
                 ],
                 "model": self._MODEL,
                 "stream": True,
-            },  # TODO: Add optional parameters for the model
+                "temperature": 0.0,
+            },
         ) as response:
             await self._assert_api_call_is_success(response)