diff --git a/up2b/up2b_lib/up2b_api/__init__.py b/up2b/up2b_lib/up2b_api/__init__.py
index 6b67ccc..c8b074b 100644
--- a/up2b/up2b_lib/up2b_api/__init__.py
+++ b/up2b/up2b_lib/up2b_api/__init__.py
@@ -160,7 +160,7 @@ def _save_auth_info(self, auth_info: Dict[str, str]):
             logger.fatal("save auth configure failed", error=e)
 
     def _exceed_max_size(
-        self, images: Tuple[Union[ImageType, DownloadErrorResponse]]
+        self, images: Tuple[Union[ImageType, DownloadErrorResponse], ...]
     ) -> Tuple[bool, Optional[str]]:
         for img in images:
             if isinstance(img, DownloadErrorResponse):
@@ -173,7 +173,7 @@ def _exceed_max_size(
         return False, None
 
     def _check_images_valid(
-        self, images: Tuple[Union[ImageType, DownloadErrorResponse]]
+        self, images: Tuple[Union[ImageType, DownloadErrorResponse], ...]
     ):
         """
         Check if all images exceed the max size or can be compressed
diff --git a/up2b/up2b_lib/up2b_api/__init__.pyi b/up2b/up2b_lib/up2b_api/__init__.pyi
index 4808a98..e5a8cda 100644
--- a/up2b/up2b_lib/up2b_api/__init__.pyi
+++ b/up2b/up2b_lib/up2b_api/__init__.pyi
@@ -66,6 +66,8 @@ class ImageBedAbstract(ABC):
     @abstractmethod
     def description(self) -> str: ...
 
+Images = Tuple[Union[ImageType, DownloadErrorResponse], ...]
+
 class Base:
     image_bed_code: ImageBedCode
     max_size: int
@@ -89,12 +91,8 @@ class Base:
     def check_login(self) -> None: ...
     def _read_auth_info(self) -> Optional[AuthInfo]: ...
     def _save_auth_info(self, auth_info: Dict[str, str]) -> None: ...
-    def _exceed_max_size(
-        self, images: Tuple[Union[ImageType, DownloadErrorResponse]]
-    ) -> Tuple[bool, Optional[str]]: ...
-    def _check_images_valid(
-        self, images: Tuple[Union[ImageType, DownloadErrorResponse]]
-    ): ...
+    def _exceed_max_size(self, images: Images) -> Tuple[bool, Optional[str]]: ...
+    def _check_images_valid(self, images: Images): ...
     def _compress_image(self, image: ImageType) -> ImageType: ...
     def _add_watermark(self, image_path: ImagePath) -> ImagePath: ...
     def _clear_cache(self) -> None: ...
diff --git a/up2b/up2b_lib/utils.py b/up2b/up2b_lib/utils.py
index 65f6435..773631d 100644
--- a/up2b/up2b_lib/utils.py
+++ b/up2b/up2b_lib/utils.py
@@ -42,7 +42,7 @@ def timeout() -> float:
         return DEFAULT_TIMEOUT
 
 
-def check_image_exists(images: Tuple[Union[ImageType, DownloadErrorResponse]]):
+def check_image_exists(images: Tuple[Union[ImageType, DownloadErrorResponse], ...]):
     for image in images:
         if isinstance(image, Path) and not image.exists():
             raise FileNotFoundError(image)