diff --git a/gdextension/gdextension_interface.h b/gdextension/gdextension_interface.h
index 05eb332..7e9e4ea 100644
--- a/gdextension/gdextension_interface.h
+++ b/gdextension/gdextension_interface.h
@@ -510,7 +510,7 @@ typedef struct {
 	GDExtensionScriptInstanceGet get_func;
 	GDExtensionScriptInstanceGetPropertyList get_property_list_func;
 	GDExtensionScriptInstanceFreePropertyList free_property_list_func;
-	GDExtensionScriptInstanceGetClassCategory get_class_category_func;
+	GDExtensionScriptInstanceGetClassCategory get_class_category_func; // Optional. Set to NULL for the default behavior.
 
 	GDExtensionScriptInstancePropertyCanRevert property_can_revert_func;
 	GDExtensionScriptInstancePropertyGetRevert property_get_revert_func;
@@ -2147,6 +2147,17 @@ typedef void *(*GDExtensionInterfaceObjectGetInstanceBinding)(GDExtensionObjectP
  */
 typedef void (*GDExtensionInterfaceObjectSetInstanceBinding)(GDExtensionObjectPtr p_o, void *p_token, void *p_binding, const GDExtensionInstanceBindingCallbacks *p_callbacks);
 
+/**
+ * @name object_free_instance_binding
+ * @since 4.2
+ *
+ * Free an Object's instance binding.
+ *
+ * @param p_o A pointer to the Object.
+ * @param p_library A token the library received by the GDExtension's entry point function.
+ */
+typedef void (*GDExtensionInterfaceObjectFreeInstanceBinding)(GDExtensionObjectPtr p_o, void *p_token);
+
 /**
  * @name object_set_instance
  * @since 4.1