diff --git a/rwx/fs/__init__.py b/rwx/fs/__init__.py
index 374a658..5767015 100644
--- a/rwx/fs/__init__.py
+++ b/rwx/fs/__init__.py
@@ -67,18 +67,37 @@ def make_directory(path: Path) -> None:
 
 
 def read_file_bytes(file_path: Path) -> bytes:
-    """Read whole file bytes."""
+    """Read whole file bytes.
+
+    :param file_path: source input file
+    :type file_path: Path
+    :rtype: bytes
+    """
     with file_path.open("br") as file_object:
         return file_object.read()
 
 
 def read_file_lines(file_path: Path, charset: str = CHARSET) -> list[str]:
-    """Read whole file lines."""
+    """Read whole file lines.
+
+    :param file_path: source input file
+    :type file_path: Path
+    :param charset: charset to use for decoding input
+    :type charset: str
+    :rtype: list[str]
+    """
     return read_file_text(file_path, charset).split(os.linesep)
 
 
 def read_file_text(file_path: Path, charset: str = CHARSET) -> str:
-    """Read whole file text."""
+    """Read whole file text.
+
+    :param file_path: source input file
+    :type file_path: Path
+    :param charset: charset to use for decoding input
+    :type charset: str
+    :rtype: str
+    """
     return read_file_bytes(file_path).decode(charset)