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vllm_mlx.tool_parsers.nemotron_tool_parser

Nemotron tool call parser for vllm-mlx.

View the complete module source at #L1-L166.

API details

Each callable below includes its exact signature, type annotations, inputs, defaults, return contract, documented exceptions, implementation source, and parsed docstring sections when the source provides them.

vllm_mlx.tool_parsers.nemotron_tool_parser

Nemotron tool call parser for vllm-mlx.

Handles NVIDIA Nemotron models' tool calling format: - v

Supports Nemotron-3-Nano-30B-A3B and similar models.

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser 

NemotronToolParser(tokenizer: PreTrainedTokenizerBase | None = None)

Bases: ToolParser

Tool call parser for NVIDIA Nemotron models.

Supports Nemotron's tool call format: Paris

Also supports JSON arguments: {"city": "Paris"}

Used when --enable-auto-tool-choice --tool-call-parser nemotron are set.

Source code in vllm_mlx/tool_parsers/abstract_tool_parser.py 
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def __init__(self, tokenizer: PreTrainedTokenizerBase | None = None):
    """
    Initialize the tool parser.

    Args:
        tokenizer: The tokenizer for the model (optional, some parsers need it)
    """
    self.model_tokenizer = tokenizer
    # State for streaming parsing
    self.current_tool_id: int = -1
    self.prev_tool_call_arr: list[dict] = []

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.TOOL_CALL_PATTERN class-attribute instance-attribute 

TOOL_CALL_PATTERN = re.compile('<tool_call>\\s*<function=([^>]+)>(.*?)</function>\\s*</tool_call>', re.DOTALL)

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.PARAM_PATTERN class-attribute instance-attribute 

PARAM_PATTERN = re.compile('<parameter=([^>]+)>\\s*(.*?)\\s*</parameter>', re.DOTALL)

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls 

extract_tool_calls(model_output: str, request: dict[str, Any] | None = None) -> ExtractedToolCallInformation

Extract tool calls from Nemotron model output.

Source code in vllm_mlx/tool_parsers/nemotron_tool_parser.py 
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def extract_tool_calls(
    self, model_output: str, request: dict[str, Any] | None = None
) -> ExtractedToolCallInformation:
    """
    Extract tool calls from Nemotron model output.
    """
    if "<tool_call>" not in model_output:
        return ExtractedToolCallInformation(
            tools_called=False, tool_calls=[], content=model_output
        )

    tool_calls = []
    cleaned_text = model_output

    matches = self.TOOL_CALL_PATTERN.findall(model_output)
    for func_name, content in matches:
        func_name = func_name.strip()

        # Try to parse content as JSON first
        content = content.strip()
        if content.startswith("{"):
            try:
                json.loads(content)
                tool_calls.append(
                    {
                        "id": generate_tool_id(),
                        "name": func_name,
                        "arguments": content,
                    }
                )
                continue
            except json.JSONDecodeError:
                pass

        # Parse parameter tags
        params = self.PARAM_PATTERN.findall(content)
        if params:
            arguments = {}
            for param_name, param_value in params:
                # Try to parse value as JSON (for nested objects)
                try:
                    arguments[param_name.strip()] = json.loads(param_value.strip())
                except json.JSONDecodeError:
                    arguments[param_name.strip()] = param_value.strip()

            tool_calls.append(
                {
                    "id": generate_tool_id(),
                    "name": func_name,
                    "arguments": json.dumps(arguments, ensure_ascii=False),
                }
            )
        elif content:
            # Raw content without parameter tags
            tool_calls.append(
                {
                    "id": generate_tool_id(),
                    "name": func_name,
                    "arguments": content,
                }
            )

    # Clean the text
    if matches:
        cleaned_text = self.TOOL_CALL_PATTERN.sub("", cleaned_text).strip()

    if tool_calls:
        return ExtractedToolCallInformation(
            tools_called=True,
            tool_calls=tool_calls,
            content=cleaned_text if cleaned_text else None,
        )
    else:
        return ExtractedToolCallInformation(
            tools_called=False, tool_calls=[], content=model_output
        )

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls_streaming 

extract_tool_calls_streaming(previous_text: str, current_text: str, delta_text: str, previous_token_ids: Sequence[int] | None = None, current_token_ids: Sequence[int] | None = None, delta_token_ids: Sequence[int] | None = None, request: dict[str, Any] | None = None) -> dict[str, Any] | None

Extract tool calls from streaming Nemotron model output.

Source code in vllm_mlx/tool_parsers/nemotron_tool_parser.py 
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def extract_tool_calls_streaming(
    self,
    previous_text: str,
    current_text: str,
    delta_text: str,
    previous_token_ids: Sequence[int] | None = None,
    current_token_ids: Sequence[int] | None = None,
    delta_token_ids: Sequence[int] | None = None,
    request: dict[str, Any] | None = None,
) -> dict[str, Any] | None:
    """
    Extract tool calls from streaming Nemotron model output.
    """
    if "<tool_call>" not in current_text:
        return {"content": delta_text}

    if "</tool_call>" in delta_text:
        result = self.extract_tool_calls(current_text)
        if result.tools_called:
            return {
                "tool_calls": [
                    {
                        "index": i,
                        "id": tc["id"],
                        "type": "function",
                        "function": {
                            "name": tc["name"],
                            "arguments": tc["arguments"],
                        },
                    }
                    for i, tc in enumerate(result.tool_calls)
                ]
            }

    return None

vllm_mlx.tool_parsers.nemotron_tool_parser.generate_tool_id 

generate_tool_id() -> str

Generate a unique tool call ID.

Source code in vllm_mlx/tool_parsers/nemotron_tool_parser.py 
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def generate_tool_id() -> str:
    """Generate a unique tool call ID."""
    return f"call_{uuid.uuid4().hex[:8]}"

Complete contract reference

Expand any definition for its exact inputs, annotations, defaults, return contract, directly raised exceptions, source-grounded behavior, and immutable line link. This section includes private and nested definitions that ordinary API generators omit.

vllm_mlx.tool_parsers.nemotron_tool_parser.generate_tool_id · function 
vllm_mlx.tool_parsers.nemotron_tool_parser.generate_tool_id() -> str

Generate a unique tool call ID.

Parameters

This callable has no explicit inputs.

Returns

  • Type: str
  • Direct return expressions: f'call_{uuid.uuid4().hex[:8]}'

Exceptions and behavior

Function generate_tool_id calls uuid.uuid4; returns f'call_{uuid.uuid4().hex[:8]}'. No direct raise statement appears in this definition.

View source #L24-L26.

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser · class 
vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser()

Tool call parser for NVIDIA Nemotron models.

Parameters

This callable has no explicit inputs.

Returns

  • Constructs: vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser

Exceptions and behavior

Class NemotronToolParser derives from ToolParser and declares 2 direct member(s). No direct raise statement appears in this definition.

View source #L30-L166.

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls · method 
vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls(model_output: str, request: dict[str, Any] | None = None) -> ExtractedToolCallInformation

Extract tool calls from Nemotron model output.

Parameters

Name Type Required Default Description
model_output str yes none Required positional or keyword input.
request dict[str, Any] \| None no None Optional positional or keyword input; defaults to None.

Returns

  • Type: ExtractedToolCallInformation
  • Direct return expressions: ExtractedToolCallInformation(tools_called=False, tool_calls=[], content=model_output); ExtractedToolCallInformation(tools_called=True, tool_calls=tool_calls, content=cleaned_text if cleaned_text else None)

Exceptions and behavior

Method NemotronToolParser.extract_tool_calls calls ExtractedToolCallInformation, self.TOOL_CALL_PATTERN.findall, func_name.strip, content.strip; has 2 explicit return paths. No direct raise statement appears in this definition.

View source #L55-L130.

vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls_streaming · method 
vllm_mlx.tool_parsers.nemotron_tool_parser.NemotronToolParser.extract_tool_calls_streaming(previous_text: str, current_text: str, delta_text: str, previous_token_ids: Sequence[int] | None = None, current_token_ids: Sequence[int] | None = None, delta_token_ids: Sequence[int] | None = None, request: dict[str, Any] | None = None) -> dict[str, Any] | None

Extract tool calls from streaming Nemotron model output.

Parameters

Name Type Required Default Description
previous_text str yes none Required positional or keyword input.
current_text str yes none Required positional or keyword input.
delta_text str yes none Required positional or keyword input.
previous_token_ids Sequence[int] \| None no None Optional positional or keyword input; defaults to None.
current_token_ids Sequence[int] \| None no None Optional positional or keyword input; defaults to None.
delta_token_ids Sequence[int] \| None no None Optional positional or keyword input; defaults to None.
request dict[str, Any] \| None no None Optional positional or keyword input; defaults to None.

Returns

  • Type: dict[str, Any] | None
  • Direct return expressions: {'content': delta_text}; {'tool_calls': [{'index': i, 'id': tc['id'], 'type': 'function', 'function': {'name': tc['name'], 'arguments': tc['argu…; None

Exceptions and behavior

Method NemotronToolParser.extract_tool_calls_streaming calls self.extract_tool_calls, enumerate; has 3 explicit return paths. No direct raise statement appears in this definition.

View source #L132-L166.

Complete symbol map

This map also includes private definitions and nested helpers. The signature column exposes every explicit input even when an internal helper has no dedicated parameter prose.

Symbol Kind Signature and inputs What it does Source
generate_tool_id function generate_tool_id() -> str Generate a unique tool call ID. #L24-L26
NemotronToolParser class NemotronToolParser() Tool call parser for NVIDIA Nemotron models. #L30-L166
NemotronToolParser.extract_tool_calls method NemotronToolParser.extract_tool_calls(model_output: str, request: dict[str, Any] \| None = None) -> ExtractedToolCallInformation Extract tool calls from Nemotron model output. #L55-L130
NemotronToolParser.extract_tool_calls_streaming method NemotronToolParser.extract_tool_calls_streaming(previous_text: str, current_text: str, delta_text: str, previous_token_ids: Sequence[int] \| None = None, current_token_ids: Sequence[int] \| None = None, delta_token_ids: Sequence[int] \| None = None, request: dict[str, Any] \| None = None) -> dict[str, Any] \| None Extract tool calls from streaming Nemotron model output. #L132-L166