--- /tmp/evalscope-sync/src-v191/evalscope/models/utils/openai.py	2026-07-21 03:18:18.000000000 +0000
+++ /data1/syy/evalscope/evalstone/evalscope/evalscope/models/utils/openai.py	2026-08-21 03:03:19.641323740 +0000
@@ -256,6 +256,8 @@
         params['timeout'] = config.timeout
     if config.max_tokens is not None:
         params['max_tokens'] = config.max_tokens
+    if config.max_completion_tokens is not None:
+        params['max_completion_tokens'] = config.max_completion_tokens
     if config.frequency_penalty is not None:
         params['frequency_penalty'] = config.frequency_penalty
     if config.stop_seqs is not None:
@@ -822,6 +824,8 @@
             continue
         collected_chunks.append(chunk)
         for choice in chunk.choices:
+            # Some proxies (e.g. Vectron) omit choice.index; default to 0.
+            choice_index = choice.index if choice.index is not None else 0
             reasoning_content = getattr(choice.delta, 'reasoning_content', None)
             if reasoning_content is None or reasoning_content == '':
                 reasoning_content = getattr(choice.delta, 'reasoning', None)
@@ -835,11 +839,11 @@
 
             # Handle reasoning content
             if reasoning_content is not None:
-                collected_reasoning[choice.index].append(str(reasoning_content))
+                collected_reasoning[choice_index].append(str(reasoning_content))
 
             # Handle regular content
             if choice.delta.content is not None:
-                collected_messages[choice.index].append(choice.delta.content)
+                collected_messages[choice_index].append(choice.delta.content)
 
             # Handle tool calls
             if hasattr(choice.delta, 'tool_calls') and choice.delta.tool_calls:
@@ -847,8 +851,8 @@
                     tool_id = tool_call.index
 
                     # Initialize tool call if not present
-                    if tool_id not in collected_tool_calls[choice.index]:
-                        collected_tool_calls[choice.index][tool_id] = {
+                    if tool_id not in collected_tool_calls[choice_index]:
+                        collected_tool_calls[choice_index][tool_id] = {
                             'id': tool_call.id if hasattr(tool_call, 'id') and tool_call.id else None,
                             'type': tool_call.type if hasattr(tool_call, 'type') and tool_call.type else None,
                             'function': {
@@ -860,15 +864,15 @@
                     # Update tool call with new chunks
                     if hasattr(tool_call, 'function'):
                         if hasattr(tool_call.function, 'name') and tool_call.function.name:
-                            collected_tool_calls[choice.index][tool_id]['function']['name'] = tool_call.function.name
+                            collected_tool_calls[choice_index][tool_id]['function']['name'] = tool_call.function.name
 
                         if hasattr(tool_call.function, 'arguments') and tool_call.function.arguments:
-                            collected_tool_calls[choice.index
+                            collected_tool_calls[choice_index
                                                  ][tool_id]['function']['arguments'] += tool_call.function.arguments
 
                     # Update ID if it was received later
                     if hasattr(tool_call, 'id') and tool_call.id:
-                        collected_tool_calls[choice.index][tool_id]['id'] = tool_call.id
+                        collected_tool_calls[choice_index][tool_id]['id'] = tool_call.id
 
     # Get all unique choice indices from all collections
     all_indices = set(collected_messages.keys()) | set(collected_reasoning.keys()) | set(collected_tool_calls.keys())
@@ -953,6 +957,8 @@
             continue
         collected_chunks.append(chunk)
         for choice in chunk.choices:
+            # Some proxies (e.g. Vectron) omit choice.index; default to 0.
+            choice_index = choice.index if choice.index is not None else 0
             reasoning_content = getattr(choice.delta, 'reasoning_content', None)
             if reasoning_content is None or reasoning_content == '':
                 reasoning_content = getattr(choice.delta, 'reasoning', None)
@@ -966,11 +972,11 @@
 
             # Handle reasoning content
             if reasoning_content is not None:
-                collected_reasoning[choice.index].append(str(reasoning_content))
+                collected_reasoning[choice_index].append(str(reasoning_content))
 
             # Handle regular content
             if choice.delta.content is not None:
-                collected_messages[choice.index].append(choice.delta.content)
+                collected_messages[choice_index].append(choice.delta.content)
 
             # Handle tool calls
             if hasattr(choice.delta, 'tool_calls') and choice.delta.tool_calls:
@@ -978,8 +984,8 @@
                     tool_id = tool_call.index
 
                     # Initialize tool call if not present
-                    if tool_id not in collected_tool_calls[choice.index]:
-                        collected_tool_calls[choice.index][tool_id] = {
+                    if tool_id not in collected_tool_calls[choice_index]:
+                        collected_tool_calls[choice_index][tool_id] = {
                             'id': tool_call.id if hasattr(tool_call, 'id') and tool_call.id else None,
                             'type': tool_call.type if hasattr(tool_call, 'type') and tool_call.type else None,
                             'function': {
@@ -991,15 +997,15 @@
                     # Update tool call with new chunks
                     if hasattr(tool_call, 'function'):
                         if hasattr(tool_call.function, 'name') and tool_call.function.name:
-                            collected_tool_calls[choice.index][tool_id]['function']['name'] = tool_call.function.name
+                            collected_tool_calls[choice_index][tool_id]['function']['name'] = tool_call.function.name
 
                         if hasattr(tool_call.function, 'arguments') and tool_call.function.arguments:
-                            collected_tool_calls[choice.index
+                            collected_tool_calls[choice_index
                                                  ][tool_id]['function']['arguments'] += tool_call.function.arguments
 
                     # Update ID if it was received later
                     if hasattr(tool_call, 'id') and tool_call.id:
-                        collected_tool_calls[choice.index][tool_id]['id'] = tool_call.id
+                        collected_tool_calls[choice_index][tool_id]['id'] = tool_call.id
 
     # Get all unique choice indices from all collections
     all_indices = set(collected_messages.keys()) | set(collected_reasoning.keys()) | set(collected_tool_calls.keys())