diff --git a/src/pyob/core_utils.py b/src/pyob/core_utils.py
index fd997af..1bf3c36 100644
--- a/src/pyob/core_utils.py
+++ b/src/pyob/core_utils.py
@@ -173,7 +173,7 @@ def generate_pr_summary(self, rel_path: str, diff_text: str) -> dict:
     def stream_gemini(
         self, prompt: str, api_key: str, on_chunk: Callable[[], None]
     ) -> str:
-        return str(stream_gemini(prompt, api_key, on_chunk))
+        return stream_gemini(prompt, api_key, on_chunk)
 
     def stream_ollama(self, prompt: str, on_chunk: Callable[[], None]) -> str:
         return str(stream_ollama(prompt, on_chunk))