core[patch]: include tool_calls in ai msg chunk serialization

libs/core/langchain_core/messages/ai.py

@@ -1,5 +1,5 @@
 import warnings
-from typing import Any, List, Literal
+from typing import Any, Dict, List, Literal
 
 from langchain_core.messages.base import (
     BaseMessage,
@@ -40,7 +40,15 @@ def get_lc_namespace(cls) -> List[str]:
         """Get the namespace of the langchain object."""
         return ["langchain", "schema", "messages"]
 
-    @root_validator
+    @property
+    def lc_attributes(self) -> Dict:
+        """Attrs to be serialized even if they are derived from other init args."""
+        return {
+            "tool_calls": self.tool_calls,
+            "invalid_tool_calls": self.invalid_tool_calls,
+        }
+
+    @root_validator()
     def _backwards_compat_tool_calls(cls, values: dict) -> dict:
         raw_tool_calls = values.get("additional_kwargs", {}).get("tool_calls")
         tool_calls = (
@@ -88,6 +96,14 @@ def get_lc_namespace(cls) -> List[str]:
         """Get the namespace of the langchain object."""
         return ["langchain", "schema", "messages"]
 
+    @property
+    def lc_attributes(self) -> Dict:
+        """Attrs to be serialized even if they are derived from other init args."""
+        return {
+            "tool_calls": self.tool_calls,
+            "invalid_tool_calls": self.invalid_tool_calls,
+        }
+
     @root_validator()
     def init_tool_calls(cls, values: dict) -> dict:
         if not values["tool_call_chunks"]:

libs/core/tests/unit_tests/messages/test_ai.py

@@ -0,0 +1,67 @@
+from langchain_core.load import dumpd, load
+from langchain_core.messages import (
+    AIMessage,
+    AIMessageChunk,
+    InvalidToolCall,
+    ToolCall,
+    ToolCallChunk,
+)
+
+
+def test_serdes_message() -> None:
+    msg = AIMessage(
+        [{"text": "blah", "type": "text"}],
+        tool_calls=[ToolCall(name="foo", args={"bar": 1}, id="baz")],
+        invalid_tool_calls=[
+            InvalidToolCall(name="foobad", args="blah", id="booz", error="bad")
+        ],
+    )
+    expected = {
+        "lc": 1,
+        "type": "constructor",
+        "id": ["langchain", "schema", "messages", "AIMessage"],
+        "kwargs": {
+            "content": [{"text": "blah", "type": "text"}],
+            "tool_calls": [{"name": "foo", "args": {"bar": 1}, "id": "baz"}],
+            "invalid_tool_calls": [
+                {"name": "foobad", "args": "blah", "id": "booz", "error": "bad"}
+            ],
+        },
+    }
+    actual = dumpd(msg)
+    assert actual == expected
+    assert load(actual) == msg
+
+
+def test_serdes_message_chunk() -> None:
+    chunk = AIMessageChunk(
+        [{"text": "blah", "type": "text"}],
+        tool_call_chunks=[
+            ToolCallChunk(name="foo", args='{"bar": 1}', id="baz", index=0),
+            ToolCallChunk(name="foobad", args="blah", id="booz", index=1),
+        ],
+    )
+    expected = {
+        "lc": 1,
+        "type": "constructor",
+        "id": ["langchain", "schema", "messages", "AIMessageChunk"],
+        "kwargs": {
+            "content": [{"text": "blah", "type": "text"}],
+            "tool_calls": [{"name": "foo", "args": {"bar": 1}, "id": "baz"}],
+            "invalid_tool_calls": [
+                {
+                    "name": "foobad",
+                    "args": "blah",
+                    "id": "booz",
+                    "error": "Malformed args.",
+                }
+            ],
+            "tool_call_chunks": [
+                {"name": "foo", "args": '{"bar": 1}', "id": "baz", "index": 0},
+                {"name": "foobad", "args": "blah", "id": "booz", "index": 1},
+            ],
+        },
+    }
+    actual = dumpd(chunk)
+    assert actual == expected
+    assert load(actual) == chunk