[BugFix]fix gpt-oss v1/completions response bug (#30608)

Signed-off-by: princepride <wangzhipeng628@gmail.com>
Signed-off-by: 汪志鹏 <wangzhipeng628@gmail.com>
Co-authored-by: Chauncey <chaunceyjiang@gmail.com>
Co-authored-by: Cyrus Leung <tlleungac@connect.ust.hk>
Co-authored-by: bbrowning <bbrownin@redhat.com>

tests/entrypoints/openai/test_response_api_with_harmony.py

 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 import importlib
+import importlib.util
 import json
 import time
 
@@ -986,3 +987,23 @@ async def test_function_call_with_previous_input_messages(
     assert (
         "aquarius" in output_text or "otter" in output_text or "tuesday" in output_text
     )
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("model_name", [MODEL_NAME])
+async def test_chat_truncation_content_not_null(client: OpenAI, model_name: str):
+    response = await client.chat.completions.create(
+        model=model_name,
+        messages=[{"role": "user", "content": "What is the role of AI in medicine?"}],
+        temperature=0.0,
+        max_tokens=250,
+    )
+
+    choice = response.choices[0]
+    assert choice.finish_reason == "length", (
+        f"Expected finish_reason='length', got {choice.finish_reason}"
+    )
+    assert choice.message.content is not None, (
+        "Content should not be None when truncated"
+    )
+    assert len(choice.message.content) > 0, "Content should not be empty"

tests/entrypoints/openai/test_serving_chat.py

@@ -955,7 +955,6 @@ class TestServingChatWithHarmony:
             input_messages,
             [
                 {"role": "system"},
-                {"role": "developer"},
                 {"role": "user", "content": messages[0]["content"]},
             ],
         )
@@ -983,7 +982,6 @@ class TestServingChatWithHarmony:
             input_messages_2,
             [
                 {"role": "system"},
-                {"role": "developer"},
                 {"role": "user"},
                 # The analysis message should be dropped on subsequent inputs because
                 # of the subsequent assistant message to the final channel.
@@ -1043,7 +1041,7 @@ class TestServingChatWithHarmony:
         )
 
         # Test the Harmony messages for the second turn's input
-        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages)
+        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages, tools=tools)
         input_messages_2, _ = serving_chat._make_request_with_harmony(req_2)
         verify_harmony_messages(
             input_messages_2,
@@ -1124,7 +1122,7 @@ class TestServingChatWithHarmony:
         )
 
         # Test the Harmony messages for the second turn's input
-        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages)
+        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages, tools=tools)
         input_messages_2, _ = serving_chat._make_request_with_harmony(req_2)
         verify_harmony_messages(
             input_messages_2,
@@ -1205,7 +1203,7 @@ class TestServingChatWithHarmony:
         )
 
         # Test the Harmony messages for the second turn's input
-        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages)
+        req_2 = ChatCompletionRequest(model=MODEL_NAME, messages=messages, tools=tools)
         input_messages_2, _ = serving_chat._make_request_with_harmony(req_2)
         verify_harmony_messages(
             input_messages_2,
@@ -1255,7 +1253,7 @@ class TestServingChatWithHarmony:
         )
 
         # Test the Harmony messages for the third turn's input
-        req_3 = ChatCompletionRequest(model=MODEL_NAME, messages=messages)
+        req_3 = ChatCompletionRequest(model=MODEL_NAME, messages=messages, tools=tools)
         input_messages_3, _ = serving_chat._make_request_with_harmony(req_3)
         verify_harmony_messages(
             input_messages_3,
@@ -1318,7 +1316,7 @@ class TestServingChatWithHarmony:
         )
 
         # Test the Harmony messages for the fourth turn's input
-        req_4 = ChatCompletionRequest(model=MODEL_NAME, messages=messages)
+        req_4 = ChatCompletionRequest(model=MODEL_NAME, messages=messages, tools=tools)
         input_messages_4, _ = serving_chat._make_request_with_harmony(req_4)
         verify_harmony_messages(
             input_messages_4,
@@ -1374,7 +1372,6 @@ class TestServingChatWithHarmony:
             input_messages,
             [
                 {"role": "system"},
-                {"role": "developer"},
                 {"role": "user", "content": messages[0]["content"]},
                 # The reasoning that would have resulted in an analysis message is
                 # dropped because of a later assistant message to the final channel.
@@ -1406,7 +1403,6 @@ class TestServingChatWithHarmony:
             input_messages,
             [
                 {"role": "system"},
-                {"role": "developer"},
                 {"role": "user", "content": messages[0]["content"]},
                 {
                     "role": "assistant",
@@ -1436,7 +1432,6 @@ class TestServingChatWithHarmony:
             input_messages,
             [
                 {"role": "system"},
-                {"role": "developer"},
                 {"role": "user", "content": messages[0]["content"]},
                 {
                     "role": "assistant",

vllm/entrypoints/openai/serving_chat.py

@@ -1828,6 +1828,7 @@ class OpenAIServingChat(OpenAIServing):
         messages.append(sys_msg)
 
         # Add developer message.
+        if request.tools:
             dev_msg = get_developer_message(
                 tools=request.tools if should_include_tools else None
             )

vllm/tool_parsers/openai_tool_parser.py

@@ -79,6 +79,15 @@ class OpenAIToolParser(ToolParser):
                 elif msg.channel == "commentary" and not msg.recipient:
                     commentary_content = msg_text
 
+        # Extract partial content from the parser state if the generation was truncated
+        if parser.current_content:
+            if parser.current_channel == "final":
+                final_content = parser.current_content
+            elif (
+                parser.current_channel == "commentary" and not parser.current_recipient
+            ):
+                commentary_content = parser.current_content
+
         return ExtractedToolCallInformation(
             tools_called=len(tool_calls) > 0,
             tool_calls=tool_calls,