diff --git a/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/BasicGenerator.scala b/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/BasicGenerator.scala
index 8543f60c11..2cd122034c 100644
--- a/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/BasicGenerator.scala
+++ b/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/BasicGenerator.scala
@@ -63,24 +63,22 @@ object BasicGenerator {
         headTag -> taggedObj
     }
 
-    val specificationExtensions = doc.paths
+    val maybeSpecificationExtensionKeys = doc.paths
       .flatMap { p =>
         p.specificationExtensions.toSeq ++ p.methods.flatMap(_.specificationExtensions.toSeq)
       }
       .groupBy(_._1)
-    val specificationExtensionWrapper = if (specificationExtensions.isEmpty) "" else "case class XSpecificationExtension[T](value: T)\n"
-    val maybeSpecificationExtensionKeys = specificationExtensions
       .map { case (keyName, pairs) =>
         val values = pairs.map(_._2)
         val `type` = SpecificationExtensionRenderer.renderCombinedType(values)
         val name = strippedToCamelCase(keyName)
         val uncapitalisedName = name.head.toLower + name.tail
         val capitalisedName = name.head.toUpper + name.tail
-        s"""type ${capitalisedName}X = ${`type`}
-           |val ${uncapitalisedName}XKey = new sttp.tapir.AttributeKey[XSpecificationExtension[${capitalisedName}X]]("$packagePath.$objName.XSpecificationExtension[$packagePath.$objName.${capitalisedName}X]")
+        s"""type ${capitalisedName}Extension = ${`type`}
+           |val ${uncapitalisedName}ExtensionKey = new sttp.tapir.AttributeKey[${capitalisedName}Extension]("$packagePath.$objName.${capitalisedName}Extension")
            |""".stripMargin
       }
-      .mkString(specificationExtensionWrapper, "\n", "")
+      .mkString("\n")
 
     val mainObj = s"""|
         |package $packagePath
diff --git a/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/EndpointGenerator.scala b/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/EndpointGenerator.scala
index a521eec65e..3a7bda28dc 100644
--- a/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/EndpointGenerator.scala
+++ b/openapi-codegen/core/src/main/scala/sttp/tapir/codegen/EndpointGenerator.scala
@@ -209,9 +209,7 @@ class EndpointGenerator {
       .map { case (k, v) =>
         val camelCaseK = strippedToCamelCase(k)
         val uncapitalisedName = camelCaseK.head.toLower + camelCaseK.tail
-        val extensionType = s"${camelCaseK.capitalize}X"
-        val wrappedValue = s"XSpecificationExtension[$extensionType](${SpecificationExtensionRenderer.renderValue(v)})"
-        s""".attribute[XSpecificationExtension[$extensionType]](${uncapitalisedName}XKey, $wrappedValue)"""
+        s""".attribute[${camelCaseK.capitalize}Extension](${uncapitalisedName}ExtensionKey, ${SpecificationExtensionRenderer.renderValue(v)})"""
       }
       .mkString("\n")
   }
diff --git a/openapi-codegen/core/src/test/scala/sttp/tapir/codegen/EndpointGeneratorSpec.scala b/openapi-codegen/core/src/test/scala/sttp/tapir/codegen/EndpointGeneratorSpec.scala
index 6aad6688b7..283620ffe5 100644
--- a/openapi-codegen/core/src/test/scala/sttp/tapir/codegen/EndpointGeneratorSpec.scala
+++ b/openapi-codegen/core/src/test/scala/sttp/tapir/codegen/EndpointGeneratorSpec.scala
@@ -262,25 +262,25 @@ class EndpointGeneratorSpec extends CompileCheckTestBase {
     )("TapirGeneratedEndpoints")
     generatedCode shouldCompile ()
     val expectedAttrDecls = Seq(
-      """.attribute[XSpecificationExtension[CustomStringExtensionOnPathX]](customStringExtensionOnPathXKey, XSpecificationExtension[CustomStringExtensionOnPathX]("another string"))""",
-      """.attribute[XSpecificationExtension[CustomStringExtensionOnOperationX]](customStringExtensionOnOperationXKey, XSpecificationExtension[CustomStringExtensionOnOperationX]("bazquux"))""",
-      """.attribute[XSpecificationExtension[CustomListExtensionOnOperationX]](customListExtensionOnOperationXKey, XSpecificationExtension[CustomListExtensionOnOperationX](Vector("baz", "quux")))""",
-      """.attribute[XSpecificationExtension[CustomMapExtensionOnPathX]](customMapExtensionOnPathXKey, XSpecificationExtension[CustomMapExtensionOnPathX](Map("bazkey" -> "bazval", "quuxkey" -> Vector("quux1", "quux2")))""",
-      """.attribute[XSpecificationExtension[CustomStringExtensionOnPathDoubleTypeX]](customStringExtensionOnPathDoubleTypeXKey, XSpecificationExtension[CustomStringExtensionOnPathDoubleTypeX](123L))"""
+      """.attribute[CustomStringExtensionOnPathExtension](customStringExtensionOnPathExtensionKey, "another string")""",
+      """.attribute[CustomStringExtensionOnOperationExtension](customStringExtensionOnOperationExtensionKey, "bazquux")""",
+      """.attribute[CustomListExtensionOnOperationExtension](customListExtensionOnOperationExtensionKey, Vector("baz", "quux"))""",
+      """.attribute[CustomMapExtensionOnPathExtension](customMapExtensionOnPathExtensionKey, Map("bazkey" -> "bazval", "quuxkey" -> Vector("quux1", "quux2"))""",
+      """.attribute[CustomStringExtensionOnPathDoubleTypeExtension](customStringExtensionOnPathDoubleTypeExtensionKey, 123L)"""
     )
     expectedAttrDecls foreach (decl => generatedCode should include(decl))
     generatedCode should include(
-      """val customMapExtensionOnOperationXKey = new sttp.tapir.AttributeKey[XSpecificationExtension[CustomMapExtensionOnOperationX]]("sttp.tapir.generated.TapirGeneratedEndpoints.XSpecificationExtension[sttp.tapir.generated.TapirGeneratedEndpoints.CustomMapExtensionOnOperationX]")""".stripMargin
+      """val customMapExtensionOnOperationExtensionKey = new sttp.tapir.AttributeKey[CustomMapExtensionOnOperationExtension]("sttp.tapir.generated.TapirGeneratedEndpoints.CustomMapExtensionOnOperationExtension")""".stripMargin
     )
     val expectedKeyDeclarations = Seq(
-      """type CustomMapExtensionOnOperationX = Map[String, Any]""",
-      """type CustomListExtensionOnPathAnyTypeX = Seq[Any]""",
-      """type CustomMapExtensionOnPathSingleValueTypeX = Map[String, String]""",
-      """type CustomListExtensionOnOperationX = Seq[String]""",
-      """type CustomStringExtensionOnPathAnyTypeX = Any""",
-      """type CustomStringExtensionOnPathDoubleTypeX = Double""",
-      """type CustomListExtensionOnPathX = Seq[String]""",
-      """type CustomStringExtensionOnPathX = String"""
+      """type CustomMapExtensionOnOperationExtension = Map[String, Any]""",
+      """type CustomListExtensionOnPathAnyTypeExtension = Seq[Any]""",
+      """type CustomMapExtensionOnPathSingleValueTypeExtension = Map[String, String]""",
+      """type CustomListExtensionOnOperationExtension = Seq[String]""",
+      """type CustomStringExtensionOnPathAnyTypeExtension = Any""",
+      """type CustomStringExtensionOnPathDoubleTypeExtension = Double""",
+      """type CustomListExtensionOnPathExtension = Seq[String]""",
+      """type CustomStringExtensionOnPathExtension = String"""
     )
     expectedKeyDeclarations foreach (decl => generatedCode should include(decl))
   }