Merging of interfaces got a bit of an overhaul in 3.0.4/5. By default interface annotations are now inherited via `allOf`. This is done by the `InheritInterfaces` processor. If this is not working for you this processor can be swapped for the `MergeInterfaces` (this used to be the default). <?php /** * @OA\Info( * version="1.0.0", * title="Example of using interfaces in swagger-php", * ) */