diff --git a/src/ModularPipelines/FileSystem/File.cs b/src/ModularPipelines/FileSystem/File.cs
index 5ed277dd20..cd98f6d97a 100644
--- a/src/ModularPipelines/FileSystem/File.cs
+++ b/src/ModularPipelines/FileSystem/File.cs
@@ -391,6 +391,7 @@ public static File GetNewTemporaryFilePath()
         return new File(fileInfo);
     }
 
+    [return: NotNullIfNotNull(parameterName: "file")]
     public static implicit operator string?(File? file)
     {
         return file?.Path;
diff --git a/src/ModularPipelines/FileSystem/Folder.cs b/src/ModularPipelines/FileSystem/Folder.cs
index f95d45fda4..476a62eb98 100644
--- a/src/ModularPipelines/FileSystem/Folder.cs
+++ b/src/ModularPipelines/FileSystem/Folder.cs
@@ -553,6 +553,7 @@ public static Folder CreateTemporaryFolder()
         return new Folder(directoryInfo);
     }
 
+    [return: NotNullIfNotNull(parameterName: "folder")]
     public static implicit operator string?(Folder? folder)
     {
         return folder?.Path;