diff --git a/pydantic_cli/examples/simple_with_custom.py b/pydantic_cli/examples/simple_with_custom.py
index 65308f6..7fdfcc6 100644
--- a/pydantic_cli/examples/simple_with_custom.py
+++ b/pydantic_cli/examples/simple_with_custom.py
@@ -1,6 +1,6 @@
 import sys
 import logging
-from typing import Union
+from typing import Union, Literal
 
 from pydantic import Field
 
@@ -17,6 +17,7 @@ class Options(Cmd):
     max_records: int = Field(10, cli=("-m", "--max-records"))
     min_filter_score: float = Field(..., cli=("-f", "--filter-score"))
     alpha: Union[int, str] = 1
+    beta: Literal["a", "b"] = "a"
 
     def run(self) -> None:
         log.info(
diff --git a/pydantic_cli/tests/test_examples_simple_with_custom.py b/pydantic_cli/tests/test_examples_simple_with_custom.py
index e5fd091..a347026 100644
--- a/pydantic_cli/tests/test_examples_simple_with_custom.py
+++ b/pydantic_cli/tests/test_examples_simple_with_custom.py
@@ -10,4 +10,4 @@ def test_simple_01(self):
         self.run_config(["-i", "/path/to/file.txt", "-f", "1.0", "-m", "2"])
 
     def test_simple_02(self):
-        self.run_config(["-i", "/path/to/file.txt", "-f", "1.0"])
+        self.run_config(["-i", "/path/to/file.txt", "-f", "1.0", "--beta", "b"])