diff --git a/schemas/legacy.json b/schemas/legacy.json
index 601c52c..16eab2d 100644
--- a/schemas/legacy.json
+++ b/schemas/legacy.json
@@ -731,7 +731,8 @@
                 "type": "number"
             },
             "Direction": {
-                "type": "string"
+                "type": "string",
+                "enum": ["less than", "greater than"]
             },
             "DtsCritOffset": {
                 "type": "number"