Update GoogleVertexLLMService default model to gemini-2.5-flash

CHANGELOG.md

@@ -33,6 +33,8 @@ reason")`.
 
 ### Changed
 
+- Updated the default model for `GoogleVertexLLMService` to `gemini-2.5-flash`.
+
 - Updated the `GoogleVertexLLMService` to use the `GoogleLLMService` as a base
   class instead of the `OpenAILLMService`.
 

src/pipecat/services/google/llm_vertex.py

@@ -99,7 +99,7 @@ class GoogleVertexLLMService(GoogleLLMService):
         *,
         credentials: Optional[str] = None,
         credentials_path: Optional[str] = None,
-        model: str = "google/gemini-2.0-flash-001",
+        model: str = "gemini-2.5-flash",
         location: Optional[str] = None,
         project_id: Optional[str] = None,
         params: Optional[GoogleLLMService.InputParams] = None,
@@ -114,7 +114,7 @@ class GoogleVertexLLMService(GoogleLLMService):
         Args:
             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").
+            model: Model identifier (e.g., "gemini-2.5-flash").
             location: GCP region for Vertex AI endpoint (e.g., "us-east4").
             project_id: Google Cloud project ID.
             params: Input parameters for the model.