From 585e0bde36abdb2ab2967fd42005cbe62459020e Mon Sep 17 00:00:00 2001
From: Federico <65908512+coval3nte@users.noreply.github.com>
Date: Wed, 27 Aug 2025 02:29:52 +0200
Subject: [PATCH] [Bugfix] UnboundLocalError when GptOss reasoning specified
 (#23054)

Signed-off-by: Federico <65908512+coval3nte@users.noreply.github.com>
---
 vllm/entrypoints/openai/serving_chat.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/vllm/entrypoints/openai/serving_chat.py b/vllm/entrypoints/openai/serving_chat.py
index 8b50153f01152..7e0e627780970 100644
--- a/vllm/entrypoints/openai/serving_chat.py
+++ b/vllm/entrypoints/openai/serving_chat.py
@@ -887,7 +887,8 @@ class OpenAIServingChat(OpenAIServing):
                         delta_message = DeltaMessage(content=delta_text)
 
                     # update the previous values for the next iteration
-                    if tool_choice_auto or self.reasoning_parser:
+                    if ((tool_choice_auto or self.reasoning_parser)
+                            and not self.use_harmony):
                         assert previous_texts is not None
                         assert all_previous_token_ids is not None
                         previous_texts[i] = current_text