diff --git a/modules/vmware/main.tf b/modules/vmware/main.tf
index 505fdd9..339d854 100644
--- a/modules/vmware/main.tf
+++ b/modules/vmware/main.tf
@@ -21,11 +21,12 @@ variable "vms" {
 }
 
 variable "cluster" {
-  type = object(
+  type = object({
       datacenter_name = string
       datastore_name = string
       resource_pool_name = string
       folder = string
+    }
   )
   description = "vSphere cluster definition"
 }