diff --git a/express/content-types.ts b/express/content-types.ts
index 219ce49..b704c33 100644
--- a/express/content-types.ts
+++ b/express/content-types.ts
@@ -1,3 +1,5 @@
+// This file belongs to the framework.  You are not expected to modify it.
+
 export type ContentType = string;
 
 // tx claude https://claude.ai/share/344fc7bd-5321-4763-af2f-b82275e9f865
diff --git a/express/http-codes.ts b/express/http-codes.ts
index 912aa8a..89a23d8 100644
--- a/express/http-codes.ts
+++ b/express/http-codes.ts
@@ -1,3 +1,5 @@
+// This file belongs to the framework.  You are not expected to modify it.
+
 export type HttpCode = {
     code: number;
     name: string;