diff --git a/src/pipecat/services/google/llm_vertex.py b/src/pipecat/services/google/llm_vertex.py
index ee66c1f20..cc0b8654e 100644
--- a/src/pipecat/services/google/llm_vertex.py
+++ b/src/pipecat/services/google/llm_vertex.py
@@ -53,12 +53,44 @@ class GoogleVertexLLMService(OpenAILLMService):
 
         Parameters:
             location: GCP region for Vertex AI endpoint (e.g., "us-east4").
+
+                .. deprecated:: 0.0.90
+                    Use `location` as a direct argument to
+                    `GoogleVertexLLMService.__init__()` instead.
+
             project_id: Google Cloud project ID.
+
+                .. deprecated:: 0.0.90
+                    Use `project_id` as a direct argument to
+                    `GoogleVertexLLMService.__init__()` instead.
         """
 
         # https://cloud.google.com/vertex-ai/generative-ai/docs/learn/locations
-        location: str = "us-east4"
-        project_id: str
+        location: Optional[str] = None
+        project_id: Optional[str] = None
+
+        def __init__(self, **kwargs):
+            """Initializes the InputParams."""
+            import warnings
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("always")
+                if "location" in kwargs and kwargs["location"] is not None:
+                    warnings.warn(
+                        "GoogleVertexLLMService.InputParams.location is deprecated. "
+                        "Please provide 'location' as a direct argument to GoogleVertexLLMService.__init__() instead.",
+                        DeprecationWarning,
+                        stacklevel=2,
+                    )
+
+                if "project_id" in kwargs and kwargs["project_id"] is not None:
+                    warnings.warn(
+                        "GoogleVertexLLMService.InputParams.project_id is deprecated. "
+                        "Please provide 'project_id' as a direct argument to GoogleVertexLLMService.__init__() instead.",
+                        DeprecationWarning,
+                        stacklevel=2,
+                    )
+            super().__init__(**kwargs)
 
     def __init__(
         self,
@@ -66,7 +98,8 @@ class GoogleVertexLLMService(OpenAILLMService):
         credentials: Optional[str] = None,
         credentials_path: Optional[str] = None,
         model: str = "google/gemini-2.0-flash-001",
-        params: Optional[InputParams] = None,
+        location: Optional[str] = None,
+        project_id: Optional[str] = None,
         **kwargs,
     ):
         """Initializes the VertexLLMService.
@@ -75,33 +108,56 @@ class GoogleVertexLLMService(OpenAILLMService):
             credentials: JSON string of service account credentials.
             credentials_path: Path to the service account JSON file.
             model: Model identifier (e.g., "google/gemini-2.0-flash-001").
-            params: Vertex AI input parameters including location and project.
+            location: GCP region for Vertex AI endpoint (e.g., "us-east4").
+            project_id: Google Cloud project ID.
             **kwargs: Additional arguments passed to OpenAILLMService.
         """
-        params = params or OpenAILLMService.InputParams()
-        base_url = self._get_base_url(params)
+        # Handle deprecated InputParams fields
+        if "params" in kwargs and isinstance(kwargs["params"], GoogleVertexLLMService.InputParams):
+            params = kwargs["params"]
+            # Extract location and project_id from params if not provided
+            # directly, for backward compatibility
+            if project_id is None:
+                project_id = params.project_id
+            if location is None:
+                location = params.location
+            # Convert to base InputParams
+            params = OpenAILLMService.InputParams(
+                **params.model_dump(exclude={"location", "project_id"}, exclude_unset=True)
+            )
+            kwargs["params"] = params
+
+        # Validate project_id and location parameters
+        # NOTE: once we remove Vertex-spcific InputParams class, we can update
+        #       __init__() signature as follows:
+        #       - location: str = "us-east4",
+        #       - project_id: str,
+        #       But for now, we need them as-is to maintain proper backward
+        #       compatibility.
+        if project_id is None:
+            raise ValueError("project_id is required")
+        if location is None:
+            location = "us-east4"  # Default location if not provided
+
+        base_url = self._get_base_url(location, project_id)
         self._api_key = self._get_api_token(credentials, credentials_path)
 
         super().__init__(
             api_key=self._api_key,
             base_url=base_url,
             model=model,
-            params=params,
             **kwargs,
         )
 
     @staticmethod
-    def _get_base_url(params: InputParams) -> str:
+    def _get_base_url(location: str, project_id: str) -> str:
         """Construct the base URL for Vertex AI API."""
         # Determine the correct API host based on location
-        if params.location == "global":
+        if location == "global":
             api_host = "aiplatform.googleapis.com"
         else:
-            api_host = f"{params.location}-aiplatform.googleapis.com"
-        return (
-            f"https://{api_host}/v1/"
-            f"projects/{params.project_id}/locations/{params.location}/endpoints/openapi"
-        )
+            api_host = f"{location}-aiplatform.googleapis.com"
+        return f"https://{api_host}/v1/projects/{project_id}/locations/{location}/endpoints/openapi"
 
     @staticmethod
     def _get_api_token(credentials: Optional[str], credentials_path: Optional[str]) -> str: