diff --git a/core/src/main/scala/sttp/tapir/attribute.scala b/core/src/main/scala/sttp/tapir/attribute.scala
index 2295bd0a04..b5bd627003 100644
--- a/core/src/main/scala/sttp/tapir/attribute.scala
+++ b/core/src/main/scala/sttp/tapir/attribute.scala
@@ -2,6 +2,8 @@ package sttp.tapir
 
 import sttp.tapir.macros.AttributeKeyMacros
 
+// TODO: use AttributeKey & AttributeMap from sttp-shared in Tapir2
+
 /** @param typeName
   *   The fully qualified name of `T`.
   * @tparam T