diff --git a/src/commonMain/kotlin/tool/Tools.kt b/src/commonMain/kotlin/tool/Tools.kt
index d42e538..adb4781 100644
--- a/src/commonMain/kotlin/tool/Tools.kt
+++ b/src/commonMain/kotlin/tool/Tools.kt
@@ -61,9 +61,9 @@ inline fun <reified T : UsableTool> toolOf(
 
   val serializer = try {
     serializer<T>()
-  } catch (e :SerializationException) {
+  } catch (e: SerializationException) {
     throw SerializationException(
-      "The class ${T::class.qualifiedName} must be annotated with @SerializableTool", e
+      nonAnnotatedToolMessage<T>(), e
     )
   }
 
@@ -72,7 +72,7 @@ inline fun <reified T : UsableTool> toolOf(
     .annotations
     .filterIsInstance<AnthropicTool>()
     .firstOrNull() ?: throw SerializationException(
-      "The class ${T::class.qualifiedName} must be annotated with @SerializableTool",
+      nonAnnotatedToolMessage<T>()
     )
 
   return Tool(
@@ -82,3 +82,7 @@ inline fun <reified T : UsableTool> toolOf(
     cacheControl = cacheControl
   )
 }
+
+@PublishedApi
+internal inline fun <reified T> nonAnnotatedToolMessage() =
+  "The class ${T::class.qualifiedName} must be annotated with @AnthropicTool"
diff --git a/src/commonTest/kotlin/tool/UsableToolTest.kt b/src/commonTest/kotlin/tool/UsableToolTest.kt
index 5f06379..c585edb 100644
--- a/src/commonTest/kotlin/tool/UsableToolTest.kt
+++ b/src/commonTest/kotlin/tool/UsableToolTest.kt
@@ -68,7 +68,7 @@ class UsableToolTest {
   @Test
   fun shouldFailToCreateToolWithoutAnthropicToolAnnotation() {
     shouldThrowWithMessage<SerializationException>(
-      "The class com.xemantic.anthropic.tool.UsableToolTest.NoAnnotationTool must be annotated with @SerializableTool"
+      "The class com.xemantic.anthropic.tool.UsableToolTest.NoAnnotationTool must be annotated with @AnthropicTool"
     ) {
       toolOf<NoAnnotationTool>()
     }
@@ -84,7 +84,7 @@ class UsableToolTest {
   @Test
   fun shouldFailToCreateToolWithOnlySerializableAnnotation() {
     shouldThrowWithMessage<SerializationException>(
-      "The class com.xemantic.anthropic.tool.UsableToolTest.OnlySerializableAnnotationTool must be annotated with @SerializableTool"
+      "The class com.xemantic.anthropic.tool.UsableToolTest.OnlySerializableAnnotationTool must be annotated with @AnthropicTool"
     ) {
       toolOf<OnlySerializableAnnotationTool>()
     }