diff --git a/payload_generator/annotated_operation.cc b/payload_generator/annotated_operation.cc
index d723004..6c7bf10 100644
--- a/payload_generator/annotated_operation.cc
+++ b/payload_generator/annotated_operation.cc
@@ -49,6 +49,10 @@
       return "SOURCE_COPY";
     case InstallOperation::SOURCE_BSDIFF:
       return "SOURCE_BSDIFF";
+    case InstallOperation::ZERO:
+      return "ZERO";
+    case InstallOperation::DISCARD:
+      return "DISCARD";
   }
   return "UNK";
 }