diff --git a/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/stable/2020-04-01/cosmos-db.json b/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/stable/2020-04-01/cosmos-db.json
index d42b4c445ae0..f86ea3f886dc 100644
--- a/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/stable/2020-04-01/cosmos-db.json
+++ b/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/stable/2020-04-01/cosmos-db.json
@@ -5281,6 +5281,7 @@
           "readOnly": true
         },
         "_ts": {
+          "type": "number",
           "description": "A system generated property that denotes the last updated timestamp of the resource.",
           "readOnly": true
         },
@@ -5288,6 +5289,11 @@
           "type": "string",
           "description": "A system generated property representing the resource etag required for optimistic concurrency control.",
           "readOnly": true
+        },
+        "_self": {
+          "type": "string",
+          "description": "A system generated property. It is the unique addressable URI for the resource.",
+          "readOnly": true
         }
       }
     },