diff --git a/comfyui_modal_sync_cloud.py b/comfyui_modal_sync_cloud.py
index 5027076..3eb02c8 100644
--- a/comfyui_modal_sync_cloud.py
+++ b/comfyui_modal_sync_cloud.py
@@ -1185,19 +1185,19 @@ def _extract_prompt_executor_error(executor: Any) -> str:
 
 def _normalize_link_output_index(value: Any) -> Any:
     """Unwrap a singleton list around a prompt-link output index when present."""
-    if isinstance(value, list) and len(value) == 1 and isinstance(value[0], int | float):
-        return value[0]
+    while isinstance(value, list) and len(value) == 1:
+        value = value[0]
     return value
 
 
 def _normalize_prompt_input_value(value: Any) -> Any:
     """Unwrap transport-added singleton lists around scalar prompt input values."""
+    while isinstance(value, list) and len(value) == 1:
+        value = value[0]
     if isinstance(value, list) and len(value) == 2 and isinstance(value[0], str):
         return [value[0], _normalize_link_output_index(value[1])]
-    if isinstance(value, list) and len(value) == 1:
-        candidate = value[0]
-        if candidate is None or isinstance(candidate, bool | int | float | str):
-            return candidate
+    if value is None or isinstance(value, bool | int | float | str):
+        return value
     return value
 
 
diff --git a/remote/modal_app.py b/remote/modal_app.py
index c0d7074..9dd4120 100644
--- a/remote/modal_app.py
+++ b/remote/modal_app.py
@@ -266,19 +266,19 @@ def _is_link(value: Any) -> bool:
 
 def _normalize_link_output_index(value: Any) -> Any:
     """Unwrap a singleton list around a prompt-link output index when present."""
-    if isinstance(value, list) and len(value) == 1 and isinstance(value[0], int | float):
-        return value[0]
+    while isinstance(value, list) and len(value) == 1:
+        value = value[0]
     return value
 
 
 def _normalize_prompt_input_value(value: Any) -> Any:
     """Unwrap transport-added singleton lists around scalar prompt input values."""
+    while isinstance(value, list) and len(value) == 1:
+        value = value[0]
     if isinstance(value, list) and len(value) == 2 and isinstance(value[0], str):
         return [value[0], _normalize_link_output_index(value[1])]
-    if isinstance(value, list) and len(value) == 1:
-        candidate = value[0]
-        if candidate is None or isinstance(candidate, bool | int | float | str):
-            return candidate
+    if value is None or isinstance(value, bool | int | float | str):
+        return value
     return value
 
 
diff --git a/tests/test_modal_executor_node.py b/tests/test_modal_executor_node.py
index ff84749..966106e 100644
--- a/tests/test_modal_executor_node.py
+++ b/tests/test_modal_executor_node.py
@@ -2498,7 +2498,7 @@ def test_local_remote_app_normalizes_wrapped_subgraph_link_indexes(
                 },
                 "remote_2": {
                     "class_type": "BoundarySink",
-                    "inputs": {"value": ["remote_1", [0]]},
+                    "inputs": {"value": [[["remote_1", [0]]]]},
                     "_meta": {},
                 },
             },
@@ -2512,7 +2512,7 @@ def test_local_remote_app_normalizes_wrapped_subgraph_link_indexes(
                 {
                     "proxy_output_name": "remote_2_value",
                     "node_id": "remote_2",
-                    "output_index": [0],
+                    "output_index": [[0]],
                     "io_type": "INT",
                     "is_list": False,
                 }