diff --git a/prototype/Doubt.xcodeproj/xcshareddata/xcschemes/doubt-difftool.xcscheme b/prototype/Doubt.xcodeproj/xcshareddata/xcschemes/doubt-difftool.xcscheme
index 49622f28e..a564269a1 100644
--- a/prototype/Doubt.xcodeproj/xcshareddata/xcschemes/doubt-difftool.xcscheme
+++ b/prototype/Doubt.xcodeproj/xcshareddata/xcschemes/doubt-difftool.xcscheme
@@ -71,7 +71,7 @@
             isEnabled = "YES">
          </CommandLineArgument>
          <CommandLineArgument
-            argument = "$(SRCROOT)/UI/diff.json"
+            argument = "$(SRCROOT)/UI/doubt-difftool.js.json"
             isEnabled = "YES">
          </CommandLineArgument>
          <CommandLineArgument