anthropic[patch]: handle lists in function calling

libs/partners/anthropic/langchain_anthropic/experimental.py

@@ -69,6 +69,16 @@
 </parameter>"""
 
 
+def _get_type(parameter: Dict[str, Any]) -> str:
+    if "type" in parameter:
+        return parameter["type"]
+    if "anyOf" in parameter:
+        return json.dumps({"anyOf": parameter["anyOf"]})
+    if "allOf" in parameter:
+        return json.dumps({"allOf": parameter["allOf"]})
+    return json.dumps(parameter)
+
+
 def get_system_message(tools: List[Dict]) -> str:
     tools_data: List[Dict] = [
         {
@@ -78,7 +88,7 @@ def get_system_message(tools: List[Dict]) -> str:
                 [
                     TOOL_PARAMETER_FORMAT.format(
                         parameter_name=name,
-                        parameter_type=parameter["type"],
+                        parameter_type=_get_type(parameter),
                         parameter_description=parameter.get("description"),
                     )
                     for name, parameter in tool["parameters"]["properties"].items()
@@ -118,21 +128,44 @@ def _xml_to_dict(t: Any) -> Union[str, Dict[str, Any]]:
     return d
 
 
-def _xml_to_tool_calls(elem: Any) -> List[Dict[str, Any]]:
+def _xml_to_function_call(invoke: Any, tools: List[Dict]) -> Dict[str, Any]:
+    name = invoke.find("tool_name").text
+    arguments = _xml_to_dict(invoke.find("parameters"))
+
+    # make list elements in arguments actually lists
+    filtered_tools = [tool for tool in tools if tool["name"] == name]
+    if len(filtered_tools) > 0 and not isinstance(arguments, str):
+        tool = filtered_tools[0]
+        for key, value in arguments.items():
+            if key in tool["parameters"]["properties"]:
+                if "type" in tool["parameters"]["properties"][key]:
+                    if tool["parameters"]["properties"][key][
+                        "type"
+                    ] == "array" and not isinstance(value, list):
+                        arguments[key] = [value]
+                    if (
+                        tool["parameters"]["properties"][key]["type"] != "object"
+                        and isinstance(value, dict)
+                        and len(value.keys()) == 1
+                    ):
+                        arguments[key] = list(value.values())[0]
+
+    return {
+        "function": {
+            "name": name,
+            "arguments": json.dumps(arguments),
+        },
+        "type": "function",
+    }
+
+
+def _xml_to_tool_calls(elem: Any, tools: List[Dict]) -> List[Dict[str, Any]]:
     """
     Convert an XML element and its children into a dictionary of dictionaries.
     """
     invokes = elem.findall("invoke")
-    return [
-        {
-            "function": {
-                "name": invoke.find("tool_name").text,
-                "arguments": json.dumps(_xml_to_dict(invoke.find("parameters"))),
-            },
-            "type": "function",
-        }
-        for invoke in invokes
-    ]
+
+    return [_xml_to_function_call(invoke, tools) for invoke in invokes]
 
 
 @beta()
@@ -262,7 +295,7 @@ def _format_output(self, data: Any, **kwargs: Any) -> ChatResult:
                 xml_text = text[start:end]
 
                 xml = self._xmllib.fromstring(xml_text)
-                additional_kwargs["tool_calls"] = _xml_to_tool_calls(xml)
+                additional_kwargs["tool_calls"] = _xml_to_tool_calls(xml, tools)
                 text = ""
             except Exception:
                 pass

libs/partners/anthropic/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "langchain-anthropic"
-version = "0.1.2"
+version = "0.1.3"
 description = "An integration package connecting AnthropicMessages and LangChain"
 authors = []
 readme = "README.md"
@@ -14,7 +14,7 @@ license = "MIT"
 python = ">=3.8.1,<4.0"
 langchain-core = "^0.1"
 anthropic = ">=0.17.0,<1"
-defusedxml = {version = "^0.7.1", optional = true}
+defusedxml = { version = "^0.7.1", optional = true }
 
 [tool.poetry.group.test]
 optional = true

libs/partners/anthropic/tests/integration_tests/test_experimental.py

@@ -1,9 +1,11 @@
 """Test ChatAnthropic chat model."""
 
 import json
+from enum import Enum
+from typing import List, Optional
 
 from langchain_core.prompts import ChatPromptTemplate
-from langchain_core.pydantic_v1 import BaseModel
+from langchain_core.pydantic_v1 import BaseModel, Field
 
 from langchain_anthropic.experimental import ChatAnthropicTools
 
@@ -129,3 +131,49 @@ class Person(BaseModel):
     assert isinstance(result, Person)
     assert result.name == "Erick"
     assert result.age == 27
+
+
+def test_anthropic_complex_structured_output() -> None:
+    class ToneEnum(str, Enum):
+        positive = "positive"
+        negative = "negative"
+
+    class Email(BaseModel):
+        """Relevant information about an email."""
+
+        sender: Optional[str] = Field(
+            None, description="The sender's name, if available"
+        )
+        sender_phone_number: Optional[str] = Field(
+            None, description="The sender's phone number, if available"
+        )
+        sender_address: Optional[str] = Field(
+            None, description="The sender's address, if available"
+        )
+        action_items: List[str] = Field(
+            ..., description="A list of action items requested by the email"
+        )
+        topic: str = Field(
+            ..., description="High level description of what the email is about"
+        )
+        tone: ToneEnum = Field(..., description="The tone of the email.")
+
+    prompt = ChatPromptTemplate.from_messages(
+        [
+            (
+                "human",
+                "What can you tell me about the following email? Make sure to answer in the correct format: {email}",  # noqa: E501
+            ),
+        ]
+    )
+
+    llm = ChatAnthropicTools(temperature=0, model_name="claude-3-sonnet-20240229")
+
+    extraction_chain = prompt | llm.with_structured_output(Email)
+
+    response = extraction_chain.invoke(
+        {
+            "email": "From: Erick. The email is about the new project. The tone is positive. The action items are to send the report and to schedule a meeting."  # noqa: E501
+        }
+    )  # noqa: E501
+    assert isinstance(response, Email)