diff --git a/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/preview/2021-03-01-preview/managedCassandra.json b/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/preview/2021-03-01-preview/managedCassandra.json
index cbc0d8b0d4b8..2427fbdf349d 100644
--- a/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/preview/2021-03-01-preview/managedCassandra.json
+++ b/specification/cosmos-db/resource-manager/Microsoft.DocumentDB/preview/2021-03-01-preview/managedCassandra.json
@@ -839,7 +839,7 @@
               "description": "Number of hours to wait between taking a backup of the cluster. To disable backups, set this property to 0."
             },
             "prometheusEndpoint": {
-              "type": "string",
+              "$ref": "#/definitions/SeedNode",
               "description": "Hostname or IP address where the Prometheus endpoint containing data about the managed Cassandra nodes can be reached."
             },
             "repairEnabled": {