fixed forced tool calls on gemini-preview models

libs/vertexai/langchain_google_vertexai/_utils.py

@@ -123,6 +123,13 @@ class GoogleModelFamily(str, Enum):
 
     @classmethod
     def _missing_(cls, value: Any) -> "GoogleModelFamily":
+        # https://cloud.google.com/vertex-ai/generative-ai/docs/learn/model-versioning
+        if value.lower() in [
+            "gemini-1.5-flash-preview-0514",
+            "gemini-1.5-pro-preview-0514",
+            "gemini-1.5-pro-preview-0409",
+        ]:
+            return GoogleModelFamily.GEMINI_ADVANCED
         if "gemini" in value.lower():
             return GoogleModelFamily.GEMINI
         if "code" in value.lower():

libs/vertexai/langchain_google_vertexai/chat_models.py

@@ -1137,7 +1137,7 @@ def bind_tools(
             )
         vertexai_tool = _format_to_gapic_tool(tools)
         if tool_choice:
-            all_names = [f["name"] for f in vertexai_tool.function_declarations]
+            all_names = [f.name for f in vertexai_tool.function_declarations]
             tool_config = _tool_choice_to_tool_config(tool_choice, all_names)
         # Bind dicts for easier serialization/deserialization.
         return self.bind(tools=[vertexai_tool], tool_config=tool_config, **kwargs)

libs/vertexai/tests/unit_tests/test_utils.py

@@ -0,0 +1,47 @@
+from typing import List
+
+import pytest
+
+from langchain_google_vertexai._utils import GoogleModelFamily
+
+
+@pytest.mark.parametrize(
+    "srcs,exp",
+    [
+        (
+            [
+                "chat-bison@001",
+                "text-bison@002",
+            ],
+            GoogleModelFamily.PALM,
+        ),
+        (
+            [
+                "code-bison@002",
+                "code-gecko@002",
+            ],
+            GoogleModelFamily.CODEY,
+        ),
+        (
+            [
+                "gemini-1.0-pro-001",
+                "gemini-1.0-pro-002",
+                "gemini-1.0-pro-vision-001",
+                "gemini-1.0-pro-vision",
+            ],
+            GoogleModelFamily.GEMINI,
+        ),
+        (
+            [
+                "gemini-1.5-flash-preview-0514",
+                "gemini-1.5-pro-preview-0514",
+                "gemini-1.5-pro-preview-0409",
+            ],
+            GoogleModelFamily.GEMINI_ADVANCED,
+        ),
+    ],
+)
+def test_google_model_family(srcs: List[str], exp: GoogleModelFamily):
+    for src in srcs:
+        res = GoogleModelFamily(src)
+        assert res == exp