[Bugfix] Multiple fixes for gpt-oss Chat Completion prompting (#28729)

Signed-off-by: Ben Browning <bbrownin@redhat.com>
Co-authored-by: Chauncey <chaunceyjiang@gmail.com>
This commit is contained in:
Ben Browning
2025-12-11 23:59:53 -05:00
committed by GitHub
parent fe1787107e
commit 8f8fda261a
6 changed files with 1749 additions and 139 deletions

View File

@@ -232,7 +232,177 @@ def parse_response_input(
return msg
def parse_chat_inputs_to_harmony_messages(chat_msgs: list) -> list[Message]:
"""
Parse a list of messages from request.messages in the Chat Completion API to
Harmony messages.
"""
msgs: list[Message] = []
tool_id_names: dict[str, str] = {}
# Collect tool id to name mappings for tool response recipient values
for chat_msg in chat_msgs:
for tool_call in chat_msg.get("tool_calls", []):
tool_id_names[tool_call.get("id")] = tool_call.get("function", {}).get(
"name"
)
for chat_msg in chat_msgs:
msgs.extend(parse_chat_input_to_harmony_message(chat_msg, tool_id_names))
msgs = auto_drop_analysis_messages(msgs)
return msgs
def auto_drop_analysis_messages(msgs: list[Message]) -> list[Message]:
"""
Harmony models expect the analysis messages (representing raw chain of thought) to
be dropped after an assistant message to the final channel is produced from the
reasoning of those messages.
The openai-harmony library does this if the very last assistant message is to the
final channel, but it does not handle the case where we're in longer multi-turn
conversations and the client gave us reasoning content from previous turns of
the conversation with multiple assistant messages to the final channel in the
conversation.
So, we find the index of the last assistant message to the final channel and drop
all analysis messages that precede it, leaving only the analysis messages that
are relevant to the current part of the conversation.
"""
last_assistant_final_index = -1
for i in range(len(msgs) - 1, -1, -1):
msg = msgs[i]
if msg.author.role == "assistant" and msg.channel == "final":
last_assistant_final_index = i
break
cleaned_msgs: list[Message] = []
for i, msg in enumerate(msgs):
if i < last_assistant_final_index and msg.channel == "analysis":
continue
cleaned_msgs.append(msg)
return cleaned_msgs
def flatten_chat_text_content(content: str | list | None) -> str | None:
"""
Extract the text parts from a chat message content field and flatten them
into a single string.
"""
if isinstance(content, list):
return "".join(
item.get("text", "")
for item in content
if isinstance(item, dict) and item.get("type") == "text"
)
return content
def parse_chat_input_to_harmony_message(
chat_msg, tool_id_names: dict[str, str] | None = None
) -> list[Message]:
"""
Parse a message from request.messages in the Chat Completion API to
Harmony messages.
"""
tool_id_names = tool_id_names or {}
if not isinstance(chat_msg, dict):
# Handle Pydantic models
chat_msg = chat_msg.model_dump(exclude_none=True)
role = chat_msg.get("role")
msgs: list[Message] = []
# Assistant message with tool calls
tool_calls = chat_msg.get("tool_calls", [])
if role == "assistant" and tool_calls:
content = flatten_chat_text_content(chat_msg.get("content"))
if content:
commentary_msg = Message.from_role_and_content(Role.ASSISTANT, content)
commentary_msg = commentary_msg.with_channel("commentary")
msgs.append(commentary_msg)
reasoning_content = chat_msg.get("reasoning") or chat_msg.get(
"reasoning_content"
)
if reasoning_content:
analysis_msg = Message.from_role_and_content(
Role.ASSISTANT, reasoning_content
)
analysis_msg = analysis_msg.with_channel("analysis")
msgs.append(analysis_msg)
for call in tool_calls:
func = call.get("function", {})
name = func.get("name", "")
arguments = func.get("arguments", "") or ""
msg = Message.from_role_and_content(Role.ASSISTANT, arguments)
msg = msg.with_channel("commentary")
msg = msg.with_recipient(f"functions.{name}")
# Officially, this should be `<|constrain|>json` but there is not clear
# evidence that improves accuracy over `json` and some anecdotes to the
# contrary. Further testing of the different content_types is needed.
msg = msg.with_content_type("json")
msgs.append(msg)
return msgs
# Tool role message (tool output)
if role == "tool":
tool_call_id = chat_msg.get("tool_call_id", "")
name = tool_id_names.get(tool_call_id, "")
content = chat_msg.get("content", "") or ""
content = flatten_chat_text_content(content)
msg = (
Message.from_author_and_content(
Author.new(Role.TOOL, f"functions.{name}"), content
)
.with_channel("commentary")
.with_recipient("assistant")
)
return [msg]
# Non-tool reasoning content
reasoning_content = chat_msg.get("reasoning") or chat_msg.get("reasoning_content")
if role == "assistant" and reasoning_content:
analysis_msg = Message.from_role_and_content(Role.ASSISTANT, reasoning_content)
analysis_msg = analysis_msg.with_channel("analysis")
msgs.append(analysis_msg)
# Default: user/assistant/system messages with content
content = chat_msg.get("content") or ""
if content is None:
content = ""
if isinstance(content, str):
contents = [TextContent(text=content)]
else:
# TODO: Support refusal.
contents = [TextContent(text=c.get("text", "")) for c in content]
# Only add assistant messages if they have content, as reasoning or tool calling
# assistant messages were already added above.
if role == "assistant" and contents and contents[0].text:
msg = Message.from_role_and_contents(role, contents)
# Send non-tool assistant messages to the final channel
msg = msg.with_channel("final")
msgs.append(msg)
# For user/system/developer messages, add them directly even if no content.
elif role != "assistant":
msg = Message.from_role_and_contents(role, contents)
msgs.append(msg)
return msgs
def parse_input_to_harmony_message(chat_msg) -> list[Message]:
"""
Parse a message from request.previous_input_messages in the Responsees API to
Harmony messages.
"""
if not isinstance(chat_msg, dict):
# Handle Pydantic models
chat_msg = chat_msg.model_dump(exclude_none=True)
@@ -258,14 +428,7 @@ def parse_input_to_harmony_message(chat_msg) -> list[Message]:
if role == "tool":
name = chat_msg.get("name", "")
content = chat_msg.get("content", "") or ""
if isinstance(content, list):
# Handle array format for tool message content
# by concatenating all text parts.
content = "".join(
item.get("text", "")
for item in content
if isinstance(item, dict) and item.get("type") == "text"
)
content = flatten_chat_text_content(content)
msg = Message.from_author_and_content(
Author.new(Role.TOOL, f"functions.{name}"), content
@@ -623,20 +786,40 @@ def parse_output_into_messages(token_ids: Iterable[int]) -> StreamableParser:
def parse_chat_output(
token_ids: Sequence[int],
) -> tuple[str | None, str | None, bool]:
"""
Parse the output of a Harmony chat completion into reasoning and final content.
Note that when the `openai` tool parser is used, serving_chat only uses this
for the reasoning content and gets the final content from the tool call parser.
When the `openai` tool parser is not enabled, or when `GptOssReasoningParser` is
in use,this needs to return the final content without any tool calls parsed.
Empty reasoning or final content is returned as None instead of an empty string.
"""
parser = parse_output_into_messages(token_ids)
output_msgs = parser.messages
is_tool_call = False # TODO: update this when tool call is supported
if len(output_msgs) == 0:
# The generation has stopped during reasoning.
reasoning = parser.current_content
final_content = None
elif len(output_msgs) == 1:
# The generation has stopped during final message.
reasoning = output_msgs[0].content[0].text
final_content = parser.current_content
else:
reasoning_msg = output_msgs[:-1]
final_msg = output_msgs[-1]
reasoning = "\n".join([msg.content[0].text for msg in reasoning_msg])
final_content = final_msg.content[0].text
# Get completed messages from the parser
reasoning_texts = [
msg.content[0].text for msg in output_msgs if msg.channel == "analysis"
]
final_texts = [
msg.content[0].text for msg in output_msgs if msg.channel != "analysis"
]
# Extract partial messages from the parser
if parser.current_channel == "analysis" and parser.current_content:
reasoning_texts.append(parser.current_content)
elif parser.current_channel != "analysis" and parser.current_content:
final_texts.append(parser.current_content)
# Flatten multiple messages into a single string
reasoning: str | None = "\n".join(reasoning_texts)
final_content: str | None = "\n".join(final_texts)
# Return None instead of empty string since existing callers check for None
reasoning = reasoning or None
final_content = final_content or None
return reasoning, final_content, is_tool_call

View File

@@ -27,8 +27,8 @@ from vllm.entrypoints.openai.parser.harmony_utils import (
get_stop_tokens_for_assistant_actions,
get_streamable_parser_for_assistant,
get_system_message,
parse_chat_inputs_to_harmony_messages,
parse_chat_output,
parse_input_to_harmony_message,
render_for_completion,
)
from vllm.entrypoints.openai.protocol import (
@@ -822,6 +822,9 @@ class OpenAIServingChat(OpenAIServing):
if delta_message is not None:
harmony_tools_streamed[i] = True
elif cur_channel == "commentary":
# Tool call preambles meant to be shown to the user
delta_message = DeltaMessage(content=delta_text)
else:
delta_message = None
# handle streaming deltas for tools with named tool_choice
@@ -1770,6 +1773,11 @@ class OpenAIServingChat(OpenAIServing):
):
messages: list[OpenAIMessage] = []
# because of issues with pydantic we need to potentially
# re-serialize the tool_calls field of the request
# for more info: see comment in `maybe_serialize_tool_calls`
maybe_serialize_tool_calls(request)
# Add system message.
# NOTE: In Chat Completion API, browsing is enabled by default
# if the model supports it. TODO: Support browsing.
@@ -1788,8 +1796,7 @@ class OpenAIServingChat(OpenAIServing):
messages.append(dev_msg)
# Add user message.
for chat_msg in request.messages:
messages.extend(parse_input_to_harmony_message(chat_msg))
messages.extend(parse_chat_inputs_to_harmony_messages(request.messages))
# Render prompt token ids.
prompt_token_ids = render_for_completion(messages)

View File

@@ -43,6 +43,7 @@ class OpenAIToolParser(ToolParser):
parser = parse_output_into_messages(token_ids)
tool_calls = []
final_content = None
commentary_content = None
if len(parser.messages) > 0:
for msg in parser.messages:
@@ -75,11 +76,15 @@ class OpenAIToolParser(ToolParser):
)
elif msg.channel == "final":
final_content = msg_text
elif msg.channel == "commentary" and not msg.recipient:
commentary_content = msg_text
return ExtractedToolCallInformation(
tools_called=len(tool_calls) > 0,
tool_calls=tool_calls,
content=final_content,
# prefer final content over commentary content if both are present
# commentary content is tool call preambles meant to be shown to the user
content=final_content or commentary_content,
)
def extract_tool_calls_streaming(