add comment

Author: anthony-nhs

packages/cdk/stacks/EpsAssistMeStack.ts

@@ -93,7 +93,10 @@ export class EpsAssistMeStack extends Stack {
       stackName: props.stackName,
       collection: openSearchResources.collection
     })
+    // this dependency ensures the OpenSearch access policy is created before the VectorIndex
+    // and deleted after the VectorIndex is deleted to prevent deletion or deployment failures
     vectorIndex.node.addDependency(openSearchResources.deploymentPolicy)
+
     // Create VectorKnowledgeBase construct with Bedrock execution role
     const vectorKB = new VectorKnowledgeBaseResources(this, "VectorKB", {
       stackName: props.stackName,