fix(anthropic): sanitize tool use block when taking directly from content (#32574)

libs/partners/anthropic/langchain_anthropic/chat_models.py

@@ -365,8 +365,23 @@ def _format_messages(
                                 ),
                             )
                         else:
-                            block.pop("text", None)
+                            if tool_input := block.get("input"):
-                            content.append(block)
+                                args = tool_input
+                            elif "partial_json" in block:
+                                try:
+                                    args = json.loads(block["partial_json"] or "{}")
+                                except json.JSONDecodeError:
+                                    args = {}
+                            else:
+                                args = {}
+                            content.append(
+                                _AnthropicToolUse(
+                                    type="tool_use",
+                                    name=block["name"],
+                                    input=args,
+                                    id=block["id"],
+                                )
+                            )
                     elif block["type"] in ("server_tool_use", "mcp_tool_use"):
                         formatted_block = {
                             k: v

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

@@ -597,6 +597,47 @@ def test__format_messages_with_tool_calls() -> None:
     assert expected == actual
 
 
+def test__format_tool_use_block() -> None:
+    # Test we correctly format tool_use blocks when there is no corresponding tool_call.
+    message = AIMessage(
+        [
+            {
+                "type": "tool_use",
+                "name": "foo_1",
+                "id": "1",
+                "input": {"bar_1": "baz_1"},
+            },
+            {
+                "type": "tool_use",
+                "name": "foo_2",
+                "id": "2",
+                "input": {},
+                "partial_json": '{"bar_2": "baz_2"}',
+                "index": 1,
+            },
+        ]
+    )
+    result = _format_messages([message])
+    expected = {
+        "role": "assistant",
+        "content": [
+            {
+                "type": "tool_use",
+                "name": "foo_1",
+                "id": "1",
+                "input": {"bar_1": "baz_1"},
+            },
+            {
+                "type": "tool_use",
+                "name": "foo_2",
+                "id": "2",
+                "input": {"bar_2": "baz_2"},
+            },
+        ],
+    }
+    assert result == (None, [expected])
+
+
 def test__format_messages_with_str_content_and_tool_calls() -> None:
     system = SystemMessage("fuzz")  # type: ignore[misc]
     human = HumanMessage("foo")  # type: ignore[misc]

libs/partners/anthropic/uv.lock

@@ -1,5 +1,5 @@
 version = 1
-revision = 3
+revision = 2
 requires-python = ">=3.9"
 resolution-markers = [
     "python_full_version >= '3.13' and platform_python_implementation == 'PyPy'",
@@ -23,7 +23,7 @@ wheels = [
 
 [[package]]
 name = "anthropic"
-version = "0.60.0"
+version = "0.64.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "anyio" },
@@ -34,9 +34,9 @@ dependencies = [
     { name = "sniffio" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/4e/03/3334921dc54ed822b3dd993ae72d823a7402588521bbba3e024b3333a1fd/anthropic-0.60.0.tar.gz", hash = "sha256:a22ba187c6f4fd5afecb2fc913b960feccf72bc0d25c1b7ce0345e87caede577", size = 425983, upload-time = "2025-07-28T19:53:47.685Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/d8/4f/f2b880cba1a76f3acc7d5eb2ae217632eac1b8cef5ed3027493545c59eba/anthropic-0.64.0.tar.gz", hash = "sha256:3d496c91a63dff64f451b3e8e4b238a9640bf87b0c11d0b74ddc372ba5a3fe58", size = 427893, upload-time = "2025-08-13T17:09:49.915Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/da/bb/d84f287fb1c217b30c328af987cf8bbe3897edf0518dcc5fa39412f794ec/anthropic-0.60.0-py3-none-any.whl", hash = "sha256:65ad1f088a960217aaf82ba91ff743d6c89e9d811c6d64275b9a7c59ee9ac3c6", size = 293116, upload-time = "2025-07-28T19:53:45.944Z" },
+    { url = "https://files.pythonhosted.org/packages/a9/b2/2d268bcd5d6441df9dc0ebebc67107657edb8b0150d3fda1a5b81d1bec45/anthropic-0.64.0-py3-none-any.whl", hash = "sha256:6f5f7d913a6a95eb7f8e1bda4e75f76670e8acd8d4cd965e02e2a256b0429dd1", size = 297244, upload-time = "2025-08-13T17:09:47.908Z" },
 ]
 
 [[package]]