[Fix] Resolve tool argument types through top-level anyOf/oneOf/allOf (#36626)

python/sglang/srt/function_call/dots_detector.py

@@ -16,7 +16,10 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
-from sglang.srt.function_call.utils import _is_complete_json
+from sglang.srt.function_call.utils import (
+    _is_complete_json,
+    get_schema_properties,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -137,10 +140,9 @@ class DotsToolDetector(BaseFormatDetector):
             schema = tool.function.parameters
             if not isinstance(schema, dict):
                 break
-            properties = schema.get("properties", {})
             defs = schema.get("$defs", {})
             return (
-                properties if isinstance(properties, dict) else {},
+                get_schema_properties(schema),
                 defs if isinstance(defs, dict) else {},
             )
         return {}, {}

python/sglang/srt/function_call/glm47_moe_detector.py

@@ -17,6 +17,7 @@ from sglang.srt.function_call.core_types import (
     _GetInfoFunc,
 )
 from sglang.srt.function_call.utils import (
+    get_schema_properties,
     infer_type_from_json_schema,
     safe_literal_eval,
 )
@@ -79,15 +80,8 @@ def get_argument_type(
 
     # Get parameters safely using getattr
     params = getattr(tool.function, "parameters", None)
-    if not isinstance(params, dict):
-        return None
 
-    # Navigate to the type using dict.get() for safe access
-    properties = params.get("properties")
-    if not isinstance(properties, dict):
-        return None
-
-    arg_spec = properties.get(arg_key)
+    arg_spec = get_schema_properties(params).get(arg_key)
     if isinstance(arg_spec, dict):
         # Use the new type inference function for complex JSON Schema support
         return infer_type_from_json_schema(arg_spec)
@@ -613,8 +607,9 @@ class Glm47MoeDetector(BaseFormatDetector):
             self._last_arguments += "{}"
             self.streamed_args_for_tool[self.current_tool_id] += "{}"
             self._sent_empty_object = True
-        elif not self._last_arguments.endswith("}") and not self._sent_empty_object:
-            # Need to close brace
+        elif not self._is_first_param and not self._sent_empty_object:
+            # The streamed outer `{` is only closed here; a trailing "}" in
+            # _last_arguments may belong to a nested object value.
             calls.append(
                 ToolCallItem(
                     tool_index=self.current_tool_id,

python/sglang/srt/function_call/glm4_moe_detector.py

@@ -12,6 +12,7 @@ from sglang.srt.function_call.core_types import (
     _GetInfoFunc,
 )
 from sglang.srt.function_call.utils import (
+    get_schema_properties,
     infer_type_from_json_schema,
     safe_literal_eval,
 )
@@ -54,9 +55,7 @@ def get_argument_type(
     if func_name not in name2tool:
         return None
     tool = name2tool[func_name]
-    properties = (tool.function.parameters or {}).get("properties", {})
-    if not isinstance(properties, dict):
-        properties = {}
+    properties = get_schema_properties(tool.function.parameters)
     if arg_key not in properties:
         return None
 
@@ -572,7 +571,9 @@ class Glm4MoeDetector(BaseFormatDetector):
                             self.streamed_args_for_tool[
                                 self.current_tool_id
                             ] += empty_object
-                        elif not self._last_arguments.endswith("}"):
+                        else:
+                            # The streamed outer `{` is only closed here; a
+                            # trailing "}" may belong to a nested object value.
                             closing_brace = "}"
                             calls.append(
                                 ToolCallItem(

python/sglang/srt/function_call/hunyuan_detector.py

@@ -12,6 +12,7 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
+from sglang.srt.function_call.utils import get_schema_properties
 
 logger = logging.getLogger(__name__)
 
@@ -176,7 +177,7 @@ class HunyuanDetector(BaseFormatDetector):
             if tool.function.name == function_name:
                 if tool.function.parameters is None:
                     return {}
-                return tool.function.parameters.get("properties", {}).get(arg_key, {})
+                return get_schema_properties(tool.function.parameters).get(arg_key, {})
         return {}
 
     @staticmethod

python/sglang/srt/function_call/kimik2_detector.py

@@ -15,6 +15,7 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
+from sglang.srt.function_call.utils import get_schema_properties
 
 logger = logging.getLogger(__name__)
 
@@ -144,7 +145,7 @@ class KimiK2Detector(BaseFormatDetector):
         best_score = -1
         for tool in tools:
             params = tool.function.parameters or {}
-            props = set(params.get("properties", {}).keys())
+            props = set(get_schema_properties(params).keys())
             if not props:
                 continue
             overlap = len(arg_keys & props)

python/sglang/srt/function_call/mimo_detector.py

@@ -22,7 +22,10 @@ from sglang.srt.entrypoints.openai.protocol import Tool
 from sglang.srt.environ import envs
 from sglang.srt.function_call.base_format_detector import BaseFormatDetector
 from sglang.srt.function_call.core_types import StreamingParseResult, _GetInfoFunc
-from sglang.srt.function_call.utils import safe_literal_eval
+from sglang.srt.function_call.utils import (
+    get_schema_properties,
+    safe_literal_eval,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -31,7 +34,7 @@ def _get_param_type(func_name: str, param_name: str, tools: List[Tool]) -> str:
     """Get parameter type from tool schema."""
     for tool in tools:
         if tool.function.name == func_name:
-            props = tool.function.parameters.get("properties", {})
+            props = get_schema_properties(tool.function.parameters)
             if param_name in props:
                 return props[param_name].get("type", "string")
     return "string"

python/sglang/srt/function_call/minicpm5_detector.py

@@ -9,7 +9,10 @@ from sglang.srt.function_call.core_types import (
     StreamingParseResult,
     _GetInfoFunc,
 )
-from sglang.srt.function_call.utils import safe_literal_eval
+from sglang.srt.function_call.utils import (
+    get_schema_properties,
+    safe_literal_eval,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -38,7 +41,7 @@ def get_argument_type(
     params = tool.function.parameters or {}
     if not isinstance(params, dict):
         return None
-    return params.get("properties", {}).get(arg_key, {}).get("type")
+    return get_schema_properties(params).get(arg_key, {}).get("type")
 
 
 def parse_arguments(json_value):
@@ -84,10 +87,7 @@ class MiniCPM5Detector(BaseFormatDetector):
         name_to_required = {}
         for name, t in name_to_tool.items():
             params = t.function.parameters or {}
-            props = (
-                (params.get("properties", {}) or {}) if isinstance(params, dict) else {}
-            )
-            name_to_allowed_props[name] = set(props.keys())
+            name_to_allowed_props[name] = set(get_schema_properties(params).keys())
             req = params.get("required", []) if isinstance(params, dict) else []
             try:
                 name_to_required[name] = set(req)

python/sglang/srt/function_call/minimax_m2.py

@@ -10,6 +10,7 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
+from sglang.srt.function_call.utils import get_schema_properties
 
 logger = logging.getLogger(__name__)
 
@@ -508,8 +509,8 @@ class MinimaxM2Detector(BaseFormatDetector):
         for tool in tools:
             if tool.function.name == fname and tool.function.parameters is not None:
                 parameters = tool.function.parameters
-                if isinstance(parameters, dict) and "properties" in parameters:
-                    param_config = parameters["properties"]
+                if isinstance(parameters, dict):
+                    param_config = get_schema_properties(parameters)
                     break
 
         param_type = self._get_param_types_from_config(pname, param_config)

python/sglang/srt/function_call/minimax_m3.py

@@ -10,6 +10,7 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
+from sglang.srt.function_call.utils import get_schema_properties
 
 logger = logging.getLogger(__name__)
 
@@ -374,8 +375,8 @@ class MinimaxM3Detector(BaseFormatDetector):
         if self._schema_has_type(parent_schema, ("array",)) and child_tag == "item":
             return self._get_array_item_schema(parent_schema, parent_value)
 
-        properties = parent_schema.get("properties")
-        if isinstance(properties, dict) and child_tag in properties:
+        properties = get_schema_properties(parent_schema)
+        if child_tag in properties:
             child_schema = properties[child_tag]
             return child_schema if isinstance(child_schema, dict) else None
 

python/sglang/srt/function_call/poolside_v1_detector.py

@@ -11,7 +11,10 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
-from sglang.srt.function_call.utils import safe_literal_eval
+from sglang.srt.function_call.utils import (
+    get_schema_properties,
+    safe_literal_eval,
+)
 
 
 class _ParseState(Enum):
@@ -150,7 +153,7 @@ class PoolsideV1Detector(BaseFormatDetector):
                     and tool.function.name == func_name
                     and isinstance(tool.function.parameters, dict)
                 ):
-                    return tool.function.parameters.get("properties", {})
+                    return get_schema_properties(tool.function.parameters)
             except AttributeError:
                 continue
         return {}

python/sglang/srt/function_call/qwen3_coder_detector.py

@@ -11,6 +11,7 @@ from sglang.srt.function_call.core_types import (
     _GetInfoFunc,
 )
 from sglang.srt.function_call.utils import (
+    get_schema_properties,
     infer_type_from_json_schema,
     safe_literal_eval,
 )
@@ -80,9 +81,10 @@ class Qwen3CoderDetector(BaseFormatDetector):
                 except AttributeError:
                     return {}
 
-                if isinstance(params, dict) and "properties" in params:
-                    return params["properties"]
-                elif isinstance(params, dict):
+                if isinstance(params, dict):
+                    properties = get_schema_properties(params)
+                    if properties or "properties" in params:
+                        return properties
                     return params
                 else:
                     return {}

python/sglang/srt/function_call/spark25_detector.py

@@ -10,6 +10,7 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
+from sglang.srt.function_call.utils import get_schema_properties
 
 TOOL_CALL_BEGIN = "<tool_call>"
 TOOL_CALL_END = "</tool_call>"
@@ -47,10 +48,7 @@ def _get_param_type(tools: list[Tool], function_name: str, param_name: str) -> s
         parameters = getattr(function, "parameters", None)
         if not isinstance(parameters, dict):
             continue
-        properties = parameters.get("properties")
-        if not isinstance(properties, dict):
-            continue
-        definition = properties.get(param_name)
+        definition = get_schema_properties(parameters).get(param_name)
         if isinstance(definition, dict) and isinstance(definition.get("type"), str):
             return definition["type"]
     return "string"

python/sglang/srt/function_call/step3_detector.py

@@ -10,7 +10,10 @@ from sglang.srt.function_call.core_types import (
     ToolCallItem,
     _GetInfoFunc,
 )
-from sglang.srt.function_call.utils import safe_literal_eval
+from sglang.srt.function_call.utils import (
+    get_schema_properties,
+    safe_literal_eval,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -22,7 +25,7 @@ def get_argument_type(func_name: str, arg_key: str, defined_tools: List[Tool]) -
         return None
     tool = name2tool[func_name]
     parameters = tool.function.parameters or {}
-    properties = parameters.get("properties", {})
+    properties = get_schema_properties(parameters)
     if arg_key not in properties:
         return None
     return properties[arg_key].get("type", None)

python/sglang/srt/function_call/utils.py

@@ -304,6 +304,25 @@ def _get_tool_schema(tool: Tool) -> dict:
     }
 
 
+def get_schema_properties(schema: Any) -> Dict[str, Any]:
+    """Top-level ``properties`` of a tool ``parameters`` schema, descending
+    into ``anyOf``/``oneOf``/``allOf`` branches when the top level declares
+    none (legal JSON Schema, e.g. discriminated-union arguments)."""
+    if not isinstance(schema, dict):
+        return {}
+    properties = schema.get("properties")
+    if isinstance(properties, dict):
+        return properties
+    merged: Dict[str, Any] = {}
+    for keyword in ("anyOf", "oneOf", "allOf"):
+        branches = schema.get(keyword)
+        if isinstance(branches, list):
+            for branch in branches:
+                for key, value in get_schema_properties(branch).items():
+                    merged.setdefault(key, value)
+    return merged
+
+
 def infer_type_from_json_schema(schema: Dict[str, Any]) -> Optional[str]:
     """
     Infer the primary type of a parameter from JSON Schema.