diff --git a/main.py b/main.py
index c5723cd..d097b50 100644
--- a/main.py
+++ b/main.py
@@ -21,7 +21,13 @@ class FunctionInputs(AutomateBase):
     ttps://docs.pydantic.dev/latest/usage/models/
     """
 
-    forbidden_speckle_type: list[str] = Field(title="Forbidden speckle type")
+    forbidden_speckle_type: str = Field(
+        title="Forbidden speckle type",
+        description=(
+            "If a object has the following speckle_type,"
+            " it will be marked with an error."
+        ),
+    )
 
 
 def automate_function(