diff --git a/litellm/llms/vertex_ai_and_google_ai_studio/common_utils.py b/litellm/llms/vertex_ai_and_google_ai_studio/common_utils.py
index 71b2bbc0188..0f95b222c1b 100644
--- a/litellm/llms/vertex_ai_and_google_ai_studio/common_utils.py
+++ b/litellm/llms/vertex_ai_and_google_ai_studio/common_utils.py
@@ -164,7 +164,12 @@ def _build_vertex_schema(parameters: dict):
     # 4. Suppress unnecessary title generation:
     #    * https://github.com/pydantic/pydantic/issues/1051
     #    * http://cl/586221780
-    strip_titles(parameters)
+    strip_field(parameters, field_name="title")
+
+    strip_field(
+        parameters, field_name="$schema"
+    )  # 5. Remove $schema - json schema value, not supported by OpenAPI - causes vertex errors.
+
     return parameters
 
 
@@ -245,14 +250,14 @@ def add_object_type(schema):
         add_object_type(items)
 
 
-def strip_titles(schema):
-    schema.pop("title", None)
+def strip_field(schema, field_name: str):
+    schema.pop(field_name, None)
 
     properties = schema.get("properties", None)
     if properties is not None:
         for name, value in properties.items():
-            strip_titles(value)
+            strip_field(value, field_name)
 
     items = schema.get("items", None)
     if items is not None:
-        strip_titles(items)
+        strip_field(items, field_name)
diff --git a/litellm/llms/vertex_ai_and_google_ai_studio/gemini/vertex_and_google_ai_studio_gemini.py b/litellm/llms/vertex_ai_and_google_ai_studio/gemini/vertex_and_google_ai_studio_gemini.py
index a6e1d782a8d..914651f3dfe 100644
--- a/litellm/llms/vertex_ai_and_google_ai_studio/gemini/vertex_and_google_ai_studio_gemini.py
+++ b/litellm/llms/vertex_ai_and_google_ai_studio/gemini/vertex_and_google_ai_studio_gemini.py
@@ -400,14 +400,26 @@ class VertexGeminiConfig:
         value = _remove_additional_properties(value)
         # remove 'strict' from tools
         value = _remove_strict_from_schema(value)
+
         for tool in value:
             openai_function_object: Optional[ChatCompletionToolParamFunctionChunk] = (
                 None
             )
             if "function" in tool:  # tools list
-                openai_function_object = ChatCompletionToolParamFunctionChunk(  # type: ignore
+                _openai_function_object = ChatCompletionToolParamFunctionChunk(  # type: ignore
                     **tool["function"]
                 )
+
+                if (
+                    "parameters" in _openai_function_object
+                    and _openai_function_object["parameters"] is not None
+                ):  # OPENAI accepts JSON Schema, Google accepts OpenAPI schema.
+                    _openai_function_object["parameters"] = _build_vertex_schema(
+                        _openai_function_object["parameters"]
+                    )
+
+                openai_function_object = _openai_function_object
+
             elif "name" in tool:  # functions list
                 openai_function_object = ChatCompletionToolParamFunctionChunk(**tool)  # type: ignore