diff --git a/api/advent22_api/core/advent_image.py b/api/advent22_api/core/advent_image.py
index 8a071a0..4a14774 100644
--- a/api/advent22_api/core/advent_image.py
+++ b/api/advent22_api/core/advent_image.py
@@ -1,10 +1,13 @@
 import colorsys
 from dataclasses import dataclass
-from typing import Self
+from typing import Self, TypeAlias, cast
 
 import numpy as np
 from PIL import Image, ImageDraw, ImageFont
 
+_RGB: TypeAlias = tuple[int, int, int]
+_XY: TypeAlias = tuple[float, float]
+
 
 @dataclass(slots=True, frozen=True)
 class AdventImage:
@@ -43,7 +46,7 @@ class AdventImage:
 
     async def get_text_box(
         self,
-        xy: tuple[float, float],
+        xy: _XY,
         text: str | bytes,
         font: "ImageFont._Font",
         anchor: str | None = "mm",
@@ -81,13 +84,13 @@ class AdventImage:
         """
 
         pixel_data = self.img.crop(box).getdata()
-        mean_color: np.ndarray = np.mean(a=pixel_data, axis=0)
+        mean_color: np.ndarray = np.mean(pixel_data, axis=0)
 
-        return tuple(mean_color.astype(int)[:3])
+        return cast(_RGB, tuple(mean_color.astype(int)))
 
     async def hide_text(
         self,
-        xy: tuple[float, float],
+        xy: _XY,
         text: str | bytes,
         font: "ImageFont._Font",
         anchor: str | None = "mm",
@@ -127,7 +130,7 @@ class AdventImage:
                 xy=xy,
                 text=text,
                 font=font,
-                fill=text_color,
+                fill=cast(_RGB, text_color),
                 anchor=anchor,
                 **text_kwargs,
             )