First version of Yii Swagger intergration package was released.
It provides an integration of Swagger-PHP with Yii3 allowing to generate API documentation based on annotations such as:
/**
* @OA\Get(
* path="/api/endpoint",
* @OA\Response(response="200", description="Get default action")
* )
*/
public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
{
// ...
}

More details are available in the package readme.