diff --git a/llama_stack/providers/inline/inference/meta_reference/parallel_utils.py b/llama_stack/providers/inline/inference/meta_reference/parallel_utils.py
index 8752f06f3..9ffcf99fe 100644
--- a/llama_stack/providers/inline/inference/meta_reference/parallel_utils.py
+++ b/llama_stack/providers/inline/inference/meta_reference/parallel_utils.py
@@ -231,7 +231,7 @@ def worker_process_entrypoint(
     while True:
         try:
             task = req_gen.send(result)
-            if isinstance(task, str) and task == EndSentinel():
+            if isinstance(task, EndSentinel):
                 break
 
             assert isinstance(task, TaskRequest)