diff --git a/data/api/client-server/space_hierarchy.yaml b/data/api/client-server/space_hierarchy.yaml
index 12640b53..309b99e3 100644
--- a/data/api/client-server/space_hierarchy.yaml
+++ b/data/api/client-server/space_hierarchy.yaml
@@ -149,7 +149,7 @@ paths:
                                     format: int64
                                     description: The `origin_server_ts` for the event.
                                 required: [origin_server_ts]
-                      required: [room_type, children_state]
+                      required: [children_state]
               next_batch:
                 type: string
                 description: |-