[Bugfix] Fix Qwen3CoderToolParser anyOf/oneOf type resolution for nullable params (#37831)

Signed-off-by: AAISSJ <maze0717@g.skku.edu>
Signed-off-by: <>
Co-authored-by: 세덩 <saison@sedeong-ui-MacBookAir.local>

tests/tool_parsers/test_qwen3coder_tool_parser.py

@@ -429,6 +429,208 @@ hello world
     assert args["obj_param"] == {"key": "value"}
 
 
+def test_extract_tool_calls_anyof_type_conversion(qwen3_tool_parser):
+    """Test type conversion for anyOf/oneOf nullable schemas (Pydantic v2).
+
+    Pydantic v2 emits anyOf for Optional[T] fields, e.g.:
+        Optional[int] -> {"anyOf": [{"type": "integer"}, {"type": "null"}]}
+    The parser must extract the non-null type and apply the correct
+    conversion (int(), float(), etc.) instead of returning a raw string.
+    """
+    tools = [
+        ChatCompletionToolsParam(
+            type="function",
+            function={
+                "name": "test_anyof",
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "anyof_int": {
+                            "anyOf": [
+                                {"type": "integer"},
+                                {"type": "null"},
+                            ],
+                            "default": 5,
+                        },
+                        "anyof_str": {
+                            "anyOf": [
+                                {"type": "string"},
+                                {"type": "null"},
+                            ],
+                        },
+                        "anyof_array": {
+                            "anyOf": [
+                                {"type": "array", "items": {"type": "string"}},
+                                {"type": "null"},
+                            ],
+                        },
+                        "anyof_obj": {
+                            "anyOf": [
+                                {"type": "object"},
+                                {"type": "null"},
+                            ],
+                        },
+                        "type_as_array": {
+                            "type": ["integer", "null"],
+                        },
+                        "multi_non_null": {
+                            "anyOf": [
+                                {"type": "string"},
+                                {"type": "integer"},
+                                {"type": "null"},
+                            ],
+                        },
+                        "ref_param": {
+                            "$ref": "#/$defs/ToolInput",
+                        },
+                    },
+                },
+            },
+        )
+    ]
+
+    model_output = """<tool_call>
+<function=test_anyof>
+<parameter=anyof_int>
+5
+</parameter>
+<parameter=anyof_str>
+hello
+</parameter>
+<parameter=anyof_array>
+["a", "b", "c"]
+</parameter>
+<parameter=anyof_obj>
+{"key": "value"}
+</parameter>
+<parameter=type_as_array>
+42
+</parameter>
+<parameter=multi_non_null>
+some text
+</parameter>
+<parameter=ref_param>
+{"city": "Paris"}
+</parameter>
+</function>
+</tool_call>"""
+
+    request = ChatCompletionRequest(model=MODEL, messages=[], tools=tools)
+    extracted = qwen3_tool_parser.extract_tool_calls(model_output, request=request)
+
+    args = json.loads(extracted.tool_calls[0].function.arguments)
+    assert args["anyof_int"] == 5
+    assert isinstance(args["anyof_int"], int)
+    assert args["anyof_str"] == "hello"
+    assert isinstance(args["anyof_str"], str)
+    assert args["anyof_array"] == ["a", "b", "c"]
+    assert isinstance(args["anyof_array"], list)
+    assert args["anyof_obj"] == {"key": "value"}
+    assert isinstance(args["anyof_obj"], dict)
+    assert args["type_as_array"] == 42
+    assert isinstance(args["type_as_array"], int)
+    # Multi non-null: anyOf[string, integer, null] → first non-null is string
+    assert args["multi_non_null"] == "some text"
+    assert isinstance(args["multi_non_null"], str)
+    # $ref: treated as object, parsed via json.loads
+    assert args["ref_param"] == {"city": "Paris"}
+    assert isinstance(args["ref_param"], dict)
+
+
+def test_extract_tool_calls_anyof_type_conversion_streaming(
+    qwen3_tool_parser, qwen3_tokenizer
+):
+    """Test streaming e2e for anyOf/oneOf nullable schemas (Pydantic v2).
+
+    Verifies that the full streaming pipeline — tokenize, incrementally
+    decode, extract_tool_calls_streaming — correctly resolves types from
+    anyOf schemas and produces valid JSON with properly typed values.
+    """
+    tools = [
+        ChatCompletionToolsParam(
+            type="function",
+            function={
+                "name": "search_web",
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "query": {
+                            "anyOf": [
+                                {"type": "string"},
+                                {"type": "null"},
+                            ],
+                        },
+                        "count": {
+                            "anyOf": [
+                                {"type": "integer"},
+                                {"type": "null"},
+                            ],
+                            "default": 5,
+                        },
+                        "verbose": {
+                            "anyOf": [
+                                {"type": "boolean"},
+                                {"type": "null"},
+                            ],
+                        },
+                        "filters": {
+                            "$ref": "#/$defs/SearchFilters",
+                        },
+                    },
+                },
+            },
+        )
+    ]
+
+    model_output = """<tool_call>
+<function=search_web>
+<parameter=query>
+vllm tool parser
+</parameter>
+<parameter=count>
+10
+</parameter>
+<parameter=verbose>
+true
+</parameter>
+<parameter=filters>
+{"lang": "en", "year": 2025}
+</parameter>
+</function>
+</tool_call>"""
+
+    request = ChatCompletionRequest(model=MODEL, messages=[], tools=tools)
+
+    tool_states = {}
+    for delta_message in stream_delta_message_generator(
+        qwen3_tool_parser, qwen3_tokenizer, model_output, request
+    ):
+        if delta_message.tool_calls:
+            for tool_call in delta_message.tool_calls:
+                idx = tool_call.index
+                if idx not in tool_states:
+                    tool_states[idx] = {"name": None, "arguments": ""}
+                if tool_call.function:
+                    if tool_call.function.name:
+                        tool_states[idx]["name"] = tool_call.function.name
+                    if tool_call.function.arguments is not None:
+                        tool_states[idx]["arguments"] += tool_call.function.arguments
+
+    assert len(tool_states) == 1
+    assert tool_states[0]["name"] == "search_web"
+    assert tool_states[0]["arguments"] is not None
+    args = json.loads(tool_states[0]["arguments"])
+    assert args["query"] == "vllm tool parser"
+    assert isinstance(args["query"], str)
+    assert args["count"] == 10
+    assert isinstance(args["count"], int)
+    assert args["verbose"] is True
+    assert isinstance(args["verbose"], bool)
+    # $ref: treated as object, parsed via json.loads
+    assert args["filters"] == {"lang": "en", "year": 2025}
+    assert isinstance(args["filters"], dict)
+
+
 @pytest.mark.parametrize(
     ids=[
         "no_tools",

vllm/tool_parsers/qwen3coder_tool_parser.py

@@ -131,11 +131,58 @@ class Qwen3CoderToolParser(ToolParser):
         logger.debug("Tool '%s' is not defined in the tools list.", func_name)
         return {}
 
+    @staticmethod
+    def _first_non_null_type(type_value: Any) -> str | None:
+        """Extract the first non-null type from a type value.
+
+        Handles both scalar types ("integer") and type-as-array
+        (["integer", "null"]) per JSON Schema spec.
+        """
+        if isinstance(type_value, list):
+            return next(
+                (
+                    str(t).strip().lower()
+                    for t in type_value
+                    if t is not None and str(t).lower() != "null"
+                ),
+                None,
+            )
+        if type_value is not None and str(type_value).lower() != "null":
+            return str(type_value).strip().lower()
+        return None
+
+    def _resolve_param_type(self, param_def: dict) -> str:
+        """Resolve the effective type string from a parameter definition.
+
+        Handles direct "type" fields (including type-as-array),
+        anyOf/oneOf schemas emitted by Pydantic v2 for Optional[T],
+        and $ref schemas from Pydantic model inputs.
+        """
+        if "type" in param_def:
+            resolved = self._first_non_null_type(param_def["type"])
+            return resolved or "string"
+
+        if "anyOf" in param_def or "oneOf" in param_def:
+            variants = param_def.get("anyOf") or param_def.get("oneOf", [])
+            for v in variants:
+                if not isinstance(v, dict):
+                    continue
+                resolved = self._first_non_null_type(v.get("type"))
+                if resolved:
+                    return resolved
+
+        # $ref points to a schema definition (e.g. a Pydantic model).
+        # The referenced type is almost always an object, so treat it
+        # as such to route through json.loads.
+        if "$ref" in param_def:
+            return "object"
+
+        return "string"
+
     def _convert_param_value(
         self, param_value: str, param_name: str, param_config: dict, func_name: str
     ) -> Any:
         """Convert parameter value based on its type in the schema."""
-        # Handle null value for any type
         if param_value.lower() == "null":
             return None
 
@@ -150,19 +197,10 @@ class Qwen3CoderToolParser(ToolParser):
                 )
             return param_value
 
-        if (
-            isinstance(param_config[param_name], dict)
-            and "type" in param_config[param_name]
-        ):
-            param_type = str(param_config[param_name]["type"]).strip().lower()
-        elif (
-            isinstance(param_config[param_name], dict)
-            and "anyOf" in param_config[param_name]
-        ):
-            # anyOf has no top-level "type"; treat as object to trigger json.loads.
-            param_type = "object"
-        else:
-            param_type = "string"
+        if not isinstance(param_config[param_name], dict):
+            return param_value
+
+        param_type = self._resolve_param_type(param_config[param_name])
         if param_type in ["string", "str", "text", "varchar", "char", "enum"]:
             return param_value
         elif (