[Bug Fix] Tool signature error for Anthropic #1091

.secrets.baseline

@@ -911,15 +911,15 @@
         "filename": "test/oai/test_anthropic.py",
         "hashed_secret": "9e712c7fd95990477f7c83991f86583883fa7260",
         "is_verified": false,
-        "line_number": 51,
+        "line_number": 50,
         "is_secret": false
       },
       {
         "type": "Secret Keyword",
         "filename": "test/oai/test_anthropic.py",
         "hashed_secret": "1250ccf39e681decf5b51332888b7ccfc9a05227",
         "is_verified": false,
-        "line_number": 71,
+        "line_number": 70,
         "is_secret": false
       }
     ],
@@ -1596,5 +1596,5 @@
       }
     ]
   },
-  "generated_at": "2025-02-24T18:10:39Z"
+  "generated_at": "2025-02-25T12:38:52Z"
 }

autogen/oai/anthropic.py

@@ -365,11 +365,42 @@ def get_usage(response: ChatCompletion) -> dict:
 
     @staticmethod
     def convert_tools_to_functions(tools: list) -> list:
+        """
+        Convert tool definitions into Anthropic-compatible functions,
+        updating nested $ref paths in property schemas.
+
+        Args:
+            tools (list): List of tool definitions.
+
+        Returns:
+            list: List of functions with updated $ref paths.
+        """
+
+        def update_refs(obj, defs_keys, prop_name):
+            """Recursively update $ref values that start with "#/$defs/"."""
+            if isinstance(obj, dict):
+                for key, value in obj.items():
+                    if key == "$ref" and isinstance(value, str) and value.startswith("#/$defs/"):
+                        ref_key = value[len("#/$defs/") :]
+                        if ref_key in defs_keys:
+                            obj[key] = f"#/properties/{prop_name}/$defs/{ref_key}"
+                    else:
+                        update_refs(value, defs_keys, prop_name)
+            elif isinstance(obj, list):
+                for item in obj:
+                    update_refs(item, defs_keys, prop_name)
+
         functions = []
         for tool in tools:
             if tool.get("type") == "function" and "function" in tool:
-                functions.append(tool["function"])
-
+                function = tool["function"]
+                parameters = function.get("parameters", {})
+                properties = parameters.get("properties", {})
+                for prop_name, prop_schema in properties.items():
+                    if "$defs" in prop_schema:
+                        defs_keys = set(prop_schema["$defs"].keys())
+                        update_refs(prop_schema, defs_keys, prop_name)
+                functions.append(function)
         return functions
 
     def _add_response_format_to_system(self, params: dict[str, Any]):

test/oai/test_anthropic.py

@@ -6,7 +6,6 @@
 # SPDX-License-Identifier: MIT
 # !/usr/bin/env python3 -m pytest
 
-
 import pytest
 
 from autogen.import_utils import optional_import_block, skip_on_missing_imports
@@ -265,3 +264,70 @@ class MathReasoning(BaseModel):
 
     with pytest.raises(ValueError, match="No valid JSON found in response for Structured Output."):
         anthropic_client._extract_json_response(no_json_response)
+
+
+@skip_on_missing_imports(["anthropic"], "anthropic")
+def test_convert_tools_to_functions(anthropic_client):
+    tools = [
+        {
+            "type": "function",
+            "function": {
+                "description": "weather tool",
+                "name": "weather_tool",
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "city_name": {"type": "string", "description": "city_name"},
+                        "city_list": {
+                            "$defs": {
+                                "city_list_class": {
+                                    "properties": {
+                                        "item1": {"title": "Item1", "type": "string"},
+                                        "item2": {"title": "Item2", "type": "string"},
+                                    },
+                                    "required": ["item1", "item2"],
+                                    "title": "city_list_class",
+                                    "type": "object",
+                                }
+                            },
+                            "items": {"$ref": "#/$defs/city_list_class"},
+                            "type": "array",
+                            "description": "city_list",
+                        },
+                    },
+                    "required": ["city_name", "city_list"],
+                },
+            },
+        }
+    ]
+    expected = [
+        {
+            "description": "weather tool",
+            "name": "weather_tool",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "city_name": {"type": "string", "description": "city_name"},
+                    "city_list": {
+                        "$defs": {
+                            "city_list_class": {
+                                "properties": {
+                                    "item1": {"title": "Item1", "type": "string"},
+                                    "item2": {"title": "Item2", "type": "string"},
+                                },
+                                "required": ["item1", "item2"],
+                                "title": "city_list_class",
+                                "type": "object",
+                            }
+                        },
+                        "items": {"$ref": "#/properties/city_list/$defs/city_list_class"},
+                        "type": "array",
+                        "description": "city_list",
+                    },
+                },
+                "required": ["city_name", "city_list"],
+            },
+        }
+    ]
+    actual = anthropic_client.convert_tools_to_functions(tools=tools)
+    assert actual == expected