diff --git a/day02/__init__.py b/day02/__init__.py
index e69de29..cea3d53 100644
--- a/day02/__init__.py
+++ b/day02/__init__.py
@@ -0,0 +1 @@
+"""day02 implementation."""
diff --git a/day02/day2.py b/day02/day2.py
index ac71f83..dcfa584 100644
--- a/day02/day2.py
+++ b/day02/day2.py
@@ -1,3 +1,4 @@
+"""day2 solution."""
 from enum import StrEnum
 
 INPUT = "day02/input.txt"
@@ -5,27 +6,31 @@
 
 
 class Color(StrEnum):
+    """Color enum."""
+
     RED = "red"
     GREEN = "green"
     BLUE = "blue"
 
 
 class Draw:
+    """Class representing a draw from the bag."""
+
     red: int = 0
     green: int = 0
     blue: int = 0
 
     def __init__(self, string: str):
-        """string: `1 blue, 4 green, 5 red`"""
+        """string: ``1 blue, 4 green, 5 red``."""
         self.parse_colors_count(string)
 
     def parse_color_count(self, string: str) -> tuple[int, Color]:
-        """string: `1 blue`"""
+        """string: ``1 blue``."""
         num, color = string.split(" ")
         return int(num), Color(color)
 
     def parse_colors_count(self, string: str) -> None:
-        """string: `1 blue, 4 green, 5 red`"""
+        """string: ``1 blue, 4 green, 5 red``."""
         for color_count in string.split(","):
             color_count = color_count.strip()
             num, color = self.parse_color_count(color_count)
@@ -38,12 +43,19 @@ def parse_colors_count(self, string: str) -> None:
 
 
 class Game:
+    """Game class, showing multiple draws."""
+
     id: int
     red: int = 0
     green: int = 0
     blue: int = 0
 
     def __init__(self, string: str):
+        """Create a game from an input string.
+
+        Args:
+            string (str): a game string
+        """
         game_id_str, draw_str = string.split(":")
         self.id = int(game_id_str.replace("Game ", ""))
         self.draws = self.parse_draws(draw_str)
@@ -52,7 +64,7 @@ def __init__(self, string: str):
         self.blue = max(draw.blue for draw in self.draws)
 
     def parse_draws(self, string: str) -> list[Draw]:
-        """string: `1 blue; 4 green, 5 blue; 11 red, 3 blue`"""
+        """string: ``1 blue; 4 green, 5 blue; 11 red, 3 blue``."""
         result = []
         for draw_str in string.split(";"):
             draw_str = draw_str.strip()
@@ -61,18 +73,28 @@ def parse_draws(self, string: str) -> list[Draw]:
         return result
 
     def __str__(self) -> str:
+        """Return summary of game id and minimal rgb."""
         return f"Game {self.id}: {self.red},{self.green},{self.blue}"
 
     def power_level(self) -> int:
+        """Returns r*g*b."""
         return self.red * self.green * self.blue
 
 
 def game_filter(game: Game) -> bool:
-    """Returns true if the game satisfies the constraints of Question 1"""
+    """Returns true if the game satisfies the constraints of Question 1."""
     return game.red <= 12 and game.green <= 13 and game.blue <= 14
 
 
 def get_games(input_file: str) -> list[Game]:
+    """Gets the games from the input file.
+
+    Args:
+        input_file (str): input file name
+
+    Returns:
+        list[Game]: list of ``Game``s
+    """
     with open(input_file, "r", encoding="utf8") as file:
         games: list[Game] = []
         for line in file:
@@ -82,18 +104,18 @@ def get_games(input_file: str) -> list[Game]:
 
 
 def part1(games: list[Game]) -> int:
-    """Solves part 1"""
+    """Solves part 1."""
     filtered_games = filter(game_filter, games)
     return sum(game.id for game in filtered_games)
 
 
 def part2(games: list[Game]) -> int:
-    """Solves part2"""
+    """Solves part2."""
     return sum(game.power_level() for game in games)
 
 
 def main() -> None:
-    """Parses data into data structures, then prints out answer to q1 and q2"""
+    """Parses data into data structures, then prints out answer to q1 and q2."""
     games = get_games(INPUT)
 
     # Q1:
diff --git a/day02/tests/__init__.py b/day02/tests/__init__.py
index e69de29..8edb4c5 100644
--- a/day02/tests/__init__.py
+++ b/day02/tests/__init__.py
@@ -0,0 +1 @@
+"""tests for day02."""
diff --git a/day02/tests/test_day2.py b/day02/tests/test_day2.py
index e6725b3..ac8de3e 100644
--- a/day02/tests/test_day2.py
+++ b/day02/tests/test_day2.py
@@ -1,16 +1,19 @@
+"""tests for day02."""
 from day02.day2 import INPUT_SMALL, Draw, Game, game_filter, get_games, part1, part2
 
 
 def get_game1() -> Game:
+    """Returns a sample game."""
     return Game("Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green")
 
 
 def get_game2() -> Game:
+    """Returns another sample game."""
     return Game("Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue")
 
 
 def test_draw() -> None:
-    """Test draws"""
+    """Test draws."""
     draw1: Draw = Draw("3 blue, 4 red")
     draw2: Draw = Draw("4 blue, 3 green")
     draw3: Draw = Draw("4 blue, 3 green, 1 red")
@@ -21,7 +24,7 @@ def test_draw() -> None:
 
 
 def test_game() -> None:
-    """Test games"""
+    """Test games."""
     game1: Game = get_game1()
     game2: Game = get_game2()
 
@@ -40,7 +43,7 @@ def test_game() -> None:
 
 
 def test_part1() -> None:
-    """Tests get_games, game_filter, part1"""
+    """Tests get_games, game_filter, part1."""
     games: list[Game] = get_games(INPUT_SMALL)
 
     # test game_filter
@@ -52,7 +55,7 @@ def test_part1() -> None:
 
 
 def test_part2() -> None:
-    """Tests power"""
+    """Tests power."""
     games: list[Game] = get_games(INPUT_SMALL)
 
     # test game_filter
diff --git a/day03/__init__.py b/day03/__init__.py
index e69de29..2c2e231 100644
--- a/day03/__init__.py
+++ b/day03/__init__.py
@@ -0,0 +1 @@
+"""day03 solution."""
diff --git a/day03/lib/__init__.py b/day03/lib/__init__.py
index e69de29..5950102 100644
--- a/day03/lib/__init__.py
+++ b/day03/lib/__init__.py
@@ -0,0 +1 @@
+"""day03 classes."""
diff --git a/day03/tests/__init__.py b/day03/tests/__init__.py
index e69de29..2c2e231 100644
--- a/day03/tests/__init__.py
+++ b/day03/tests/__init__.py
@@ -0,0 +1 @@
+"""day03 solution."""