diff --git a/apps/simple/listIndex.ts b/apps/simple/listIndex.ts
index 5e03cfa019c06c1083f241ff0a6df1180bfa3c6c..5b7a5203b36431a07ce367016d3f144dce13748d 100644
--- a/apps/simple/listIndex.ts
+++ b/apps/simple/listIndex.ts
@@ -12,4 +12,6 @@ async function main() {
   console.log(response.toString());
 }
 
-main().catch(console.error);
+main().catch((e: Error) => {
+  console.error(e, e.stack);
+});
diff --git a/packages/core/src/BaseIndex.ts b/packages/core/src/BaseIndex.ts
index d8512f1b63a0a26a6b5bcab3d8260d59ed3f9a8e..f6e099eeba7835d872d894bada7a2314c415f577 100644
--- a/packages/core/src/BaseIndex.ts
+++ b/packages/core/src/BaseIndex.ts
@@ -88,9 +88,16 @@ export interface VectorIndexOptions {
   storageContext?: StorageContext;
 }
 
+interface VectorIndexConstructorProps extends BaseIndexInit<IndexDict> {
+  vectorStore: VectorStore;
+}
+
 export class VectorStoreIndex extends BaseIndex<IndexDict> {
-  private constructor(init: BaseIndexInit<IndexDict>) {
+  vectorStore: VectorStore;
+
+  private constructor(init: VectorIndexConstructorProps) {
     super(init);
+    this.vectorStore = init.vectorStore;
   }
 
   static async init(options: VectorIndexOptions): Promise<VectorStoreIndex> {