diff --git a/litellm/proxy/guardrails/guardrail_hooks/wingback/__init__.py b/litellm/proxy/guardrails/guardrail_hooks/wingback/__init__.py
index 651f7a6ed14..08d5ad30aaa 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/wingback/__init__.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/wingback/__init__.py
@@ -11,19 +11,11 @@ if TYPE_CHECKING:
 def initialize_guardrail(litellm_params: "LitellmParams", guardrail: "Guardrail") -> WingbackGuardrail:
     import litellm
 
-    base_params = litellm_params.additional_provider_specific_params or {}
-    wingback_app_id = litellm_params.wingback_app_id
-    additional_params: Final = (
-        {**base_params, "wingback_app_id": wingback_app_id}
-        if wingback_app_id and "wingback_app_id" not in base_params
-        else base_params
-    )
-
     _wingback_callback: Final = WingbackGuardrail(
         api_base=litellm_params.api_base,
         api_key=litellm_params.api_key,
-        wingback_app_id=wingback_app_id,
-        additional_provider_specific_params=additional_params,
+        wingback_app_id=litellm_params.wingback_app_id,
+        additional_provider_specific_params=litellm_params.additional_provider_specific_params,
         unreachable_fallback=litellm_params.unreachable_fallback or "fail_closed",
         fail_on_error=litellm_params.fail_on_error,
         guardrail_name=guardrail.get("guardrail_name", ""),
@@ -35,10 +27,10 @@ def initialize_guardrail(litellm_params: "LitellmParams", guardrail: "Guardrail"
     return _wingback_callback
 
 
-guardrail_initializer_registry: Final = {
+guardrail_initializer_registry: Final = {  # mutable-ok: module registry merged at import by guardrail_registry
     SupportedGuardrailIntegrations.WINGBACK.value: initialize_guardrail,
 }
 
-guardrail_class_registry: Final = {
+guardrail_class_registry: Final = {  # mutable-ok: module registry merged at import by guardrail_registry
     SupportedGuardrailIntegrations.WINGBACK.value: WingbackGuardrail,
 }
diff --git a/litellm/proxy/guardrails/guardrail_hooks/wingback/wingback.py b/litellm/proxy/guardrails/guardrail_hooks/wingback/wingback.py
index ebe83a4b60c..538bc713ffb 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/wingback/wingback.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/wingback/wingback.py
@@ -44,11 +44,15 @@ class WingbackGuardrail(GenericGuardrailAPI):
         resolved_api_base: Final = api_base or os.environ.get("WINGBACK_API_BASE") or DEFAULT_WINGBACK_API_BASE
         resolved_api_key: Final = api_key or os.environ.get("WINGBACK_INTEGRATION_API_KEY")
 
-        existing_params = additional_provider_specific_params or {}
+        existing_params: Final = additional_provider_specific_params
         additional_params: Final = (
-            {**existing_params, "wingback_app_id": wingback_app_id}
-            if wingback_app_id and "wingback_app_id" not in existing_params
-            else existing_params
+            {**existing_params, "wingback_app_id": wingback_app_id}  # mutable-ok: one-shot merge for guardrail API payload
+            if wingback_app_id and existing_params is not None and "wingback_app_id" not in existing_params
+            else (
+                {"wingback_app_id": wingback_app_id}  # mutable-ok: default provider params when only app id is configured
+                if wingback_app_id and existing_params is None
+                else existing_params
+            )
         )
 
         super().__init__(