diff --git a/packages/core/src/hierarchy.ts b/packages/core/src/hierarchy.ts
index 727d4bc7c0..98c9e5385e 100644
--- a/packages/core/src/hierarchy.ts
+++ b/packages/core/src/hierarchy.ts
@@ -19,6 +19,9 @@ import { TxProcessor } from './tx'
 
 import core from './component'
 
+/**
+ * @public
+ */
 export class Hierarchy {
   private readonly classes = new Map<Ref<Class<Obj>>, Class<Obj>>()
   private readonly attributes = new Map<Ref<Class<Obj>>, Map<string, AnyAttribute>>()