diff --git a/notebooks/azure-ai-search-custom-schema-citations.ipynb b/notebooks/azure-ai-search-custom-schema-citations.ipynb
index c848f3e..8d85f5a 100644
--- a/notebooks/azure-ai-search-custom-schema-citations.ipynb
+++ b/notebooks/azure-ai-search-custom-schema-citations.ipynb
@@ -42,6 +42,7 @@
     "| Microsoft Foundry project | A project endpoint and one chat deployment (e.g. `gpt-4.1`) |\n",
     "| Azure AI Search | An existing index, connected to the project as a `CognitiveSearch` connection |\n",
     "| Identity | `az login` — the notebook uses `DefaultAzureCredential` |\n",
+    "| Index field attributes | The fields you map to `url` and `title` must be **retrievable** and **searchable** in the index definition, or they won't appear in citation annotations |\n",
     "\n",
     "You do **not** need to re-index or rename any fields. This recipe works against the schema you\n",
     "already have.\n",