diff --git a/specification/ai/OpenAI.Assistants/tspconfig.yaml b/specification/ai/OpenAI.Assistants/tspconfig.yaml
index f48b8a1bdd7c..c1fa66723956 100644
--- a/specification/ai/OpenAI.Assistants/tspconfig.yaml
+++ b/specification/ai/OpenAI.Assistants/tspconfig.yaml
@@ -34,7 +34,7 @@ options:
     enable-sync-stack: true
     generate-tests: false
     custom-types-subpackage: "implementation.models"
-    custom-types: ""
+    custom-types: "FileListResponse,OpenAIPageableListOfAssistant,OpenAIPageableListOfAssistantFile,OpenAIPageableListOfMessageFile,OpenAIPageableListOfRunStep,OpenAIPageableListOfThreadMessage,OpenAIPageableListOfThreadRun"
   "@azure-tools/typespec-ts":
     package-dir: "openai"
     generateMetadata: false