mistral[patch]: add IDs to tool calls (#20299)

Mistral gives us one ID per response, no individual IDs for tool calls.

```python
from langchain.agents import AgentExecutor, create_tool_calling_agent, tool
from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
from langchain_mistralai import ChatMistralAI


prompt = ChatPromptTemplate.from_messages(
    [
        ("system", "You are a helpful assistant"),
        ("human", "{input}"),
        MessagesPlaceholder("agent_scratchpad"),
    ]
)
model = ChatMistralAI(model="mistral-large-latest", temperature=0)

@tool
def magic_function(input: int) -> int:
    """Applies a magic function to an input."""
    return input + 2

tools = [magic_function]

agent = create_tool_calling_agent(model, tools, prompt)
agent_executor = AgentExecutor(agent=agent, tools=tools, verbose=True)

agent_executor.invoke({"input": "what is the value of magic_function(3)?"})
```

---------

Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>

libs/core/langchain_core/messages/tool.py

@@ -67,7 +67,7 @@ def __add__(self, other: Any) -> BaseMessageChunk:  # type: ignore
 
 
 class ToolCall(TypedDict):
-    """A call to a tool.
+    """Represents a request to call a tool.
 
     Attributes:
         name: (str) the name of the tool to be called

libs/core/langchain_core/output_parsers/openai_tools.py

@@ -44,7 +44,7 @@ def parse_tool_call(
         "args": function_args or {},
     }
     if return_id:
-        parsed["id"] = raw_tool_call["id"]
+        parsed["id"] = raw_tool_call.get("id")
     return parsed
 
 
@@ -67,9 +67,9 @@ def parse_tool_calls(
     partial: bool = False,
     strict: bool = False,
     return_id: bool = True,
-) -> List[dict]:
+) -> List[Dict[str, Any]]:
     """Parse a list of tool calls."""
-    final_tools = []
+    final_tools: List[Dict[str, Any]] = []
     exceptions = []
     for tool_call in raw_tool_calls:
         try:

libs/partners/mistralai/langchain_mistralai/chat_models.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import logging
+import uuid
 from operator import itemgetter
 from typing import (
     Any,
@@ -91,14 +92,18 @@ def _convert_mistral_chat_message_to_message(
         for raw_tool_call in raw_tool_calls:
             try:
                 parsed: dict = cast(
-                    dict, parse_tool_call(raw_tool_call, return_id=False)
-                )
-                tool_calls.append(
-                    {
-                        **parsed,
-                        **{"id": None},
-                    },
+                    dict, parse_tool_call(raw_tool_call, return_id=True)
                 )
+                if not parsed["id"]:
+                    tool_call_id = uuid.uuid4().hex[:]
+                    tool_calls.append(
+                        {
+                            **parsed,
+                            **{"id": tool_call_id},
+                        },
+                    )
+                else:
+                    tool_calls.append(parsed)
             except Exception as e:
                 invalid_tool_calls.append(
                     dict(make_invalid_tool_call(raw_tool_call, str(e)))
@@ -160,15 +165,20 @@ def _convert_delta_to_message_chunk(
         if raw_tool_calls := _delta.get("tool_calls"):
             additional_kwargs["tool_calls"] = raw_tool_calls
             try:
-                tool_call_chunks = [
-                    {
-                        "name": rtc["function"].get("name"),
-                        "args": rtc["function"].get("arguments"),
-                        "id": rtc.get("id"),
-                        "index": rtc.get("index"),
-                    }
-                    for rtc in raw_tool_calls
-                ]
+                tool_call_chunks = []
+                for raw_tool_call in raw_tool_calls:
+                    if not raw_tool_call.get("index") and not raw_tool_call.get("id"):
+                        tool_call_id = uuid.uuid4().hex[:]
+                    else:
+                        tool_call_id = raw_tool_call.get("id")
+                    tool_call_chunks.append(
+                        {
+                            "name": raw_tool_call["function"].get("name"),
+                            "args": raw_tool_call["function"].get("arguments"),
+                            "id": tool_call_id,
+                            "index": raw_tool_call.get("index"),
+                        }
+                    )
             except KeyError:
                 pass
         else:
@@ -195,15 +205,17 @@ def _convert_message_to_mistral_chat_message(
         return dict(role="user", content=message.content)
     elif isinstance(message, AIMessage):
         if "tool_calls" in message.additional_kwargs:
-            tool_calls = [
-                {
+            tool_calls = []
+            for tc in message.additional_kwargs["tool_calls"]:
+                chunk = {
                     "function": {
                         "name": tc["function"]["name"],
                         "arguments": tc["function"]["arguments"],
                     }
                 }
-                for tc in message.additional_kwargs["tool_calls"]
-            ]
+                if _id := tc.get("id"):
+                    chunk["id"] = _id
+                tool_calls.append(chunk)
         else:
             tool_calls = []
         return {

libs/partners/mistralai/tests/integration_tests/test_chat_models.py

@@ -7,8 +7,6 @@
     AIMessage,
     AIMessageChunk,
     HumanMessage,
-    ToolCall,
-    ToolCallChunk,
 )
 from langchain_core.pydantic_v1 import BaseModel
 
@@ -168,9 +166,10 @@ class Person(BaseModel):
 
     result = tool_llm.invoke("Erick, 27 years old")
     assert isinstance(result, AIMessage)
-    assert result.tool_calls == [
-        ToolCall(name="Person", args={"name": "Erick", "age": 27}, id=None)
-    ]
+    assert len(result.tool_calls) == 1
+    tool_call = result.tool_calls[0]
+    assert tool_call["name"] == "Person"
+    assert tool_call["args"] == {"name": "Erick", "age": 27}
 
 
 def test_streaming_tool_call() -> None:
@@ -201,11 +200,10 @@ class Person(BaseModel):
     }
 
     assert isinstance(chunk, AIMessageChunk)
-    assert chunk.tool_call_chunks == [
-        ToolCallChunk(
-            name="Person", args='{"name": "Erick", "age": 27}', id=None, index=None
-        )
-    ]
+    assert len(chunk.tool_call_chunks) == 1
+    tool_call_chunk = chunk.tool_call_chunks[0]
+    assert tool_call_chunk["name"] == "Person"
+    assert tool_call_chunk["args"] == '{"name": "Erick", "age": 27}'
 
     # where it doesn't call the tool
     strm = tool_llm.stream("What is 2+2?")

libs/partners/mistralai/tests/unit_tests/test_chat_models.py

@@ -128,6 +128,7 @@ async def test_astream_with_callback() -> None:
 
 def test__convert_dict_to_message_tool_call() -> None:
     raw_tool_call = {
+        "id": "abc123",
         "function": {
             "arguments": '{"name":"Sally","hair_color":"green"}',
             "name": "GenerateUsername",
@@ -142,7 +143,7 @@ def test__convert_dict_to_message_tool_call() -> None:
             ToolCall(
                 name="GenerateUsername",
                 args={"name": "Sally", "hair_color": "green"},
-                id=None,
+                id="abc123",
             )
         ],
     )
@@ -152,12 +153,14 @@ def test__convert_dict_to_message_tool_call() -> None:
     # Test malformed tool call
     raw_tool_calls = [
         {
+            "id": "abc123",
             "function": {
                 "arguments": "oops",
                 "name": "GenerateUsername",
             },
         },
         {
+            "id": "def456",
             "function": {
                 "arguments": '{"name":"Sally","hair_color":"green"}',
                 "name": "GenerateUsername",
@@ -174,14 +177,14 @@ def test__convert_dict_to_message_tool_call() -> None:
                 name="GenerateUsername",
                 args="oops",
                 error="Function GenerateUsername arguments:\n\noops\n\nare not valid JSON. Received JSONDecodeError Expecting value: line 1 column 1 (char 0)",  # noqa: E501
-                id=None,
+                id="abc123",
             ),
         ],
         tool_calls=[
             ToolCall(
                 name="GenerateUsername",
                 args={"name": "Sally", "hair_color": "green"},
-                id=None,
+                id="def456",
             ),
         ],
     )