diff --git a/src/wscribe/backends/fasterwhisper.py b/src/wscribe/backends/fasterwhisper.py
index 901d70b..0e55efc 100644
--- a/src/wscribe/backends/fasterwhisper.py
+++ b/src/wscribe/backends/fasterwhisper.py
@@ -1,7 +1,7 @@
 import math
 import os
 from dataclasses import dataclass
-from typing import Any, Mapping, MutableMapping
+from typing import Any, Mapping, MutableMapping, Optional
 
 import numpy as np
 import structlog
@@ -37,7 +37,7 @@ def load(self) -> None:
         )
 
     def transcribe(
-        self, input: np.ndarray, language: str = None, silent: bool = False
+        self, input: np.ndarray, language: Optional[str] = None, silent: bool = False
     ) -> list[TranscribedData]:
         """
         Return word level transcription data.
diff --git a/src/wscribe/cli/main.py b/src/wscribe/cli/main.py
index eb7ff8b..18c8bf5 100644
--- a/src/wscribe/cli/main.py
+++ b/src/wscribe/cli/main.py
@@ -51,7 +51,7 @@ def cli():
 @click.option(
     "-g", "--gpu", help="enable gpu, disabled by default", default=False, is_flag=True
 )
-@click.option("-l", "--language", help="choose language (skips autodetection)")
+@click.option("-l", "--language", help="language code eg. en/fr (skips autodetection)")
 @click.option("-d", "--debug", help="show debug logs", default=False, is_flag=True)
 @click.option("-s", "--stats", help="print stats", default=False, is_flag=True)
 @click.option("-q", "--quiet", help="no progress bar", default=False, is_flag=True)