fix(voice): include current OpenAI TTS voices (#4535)

src/agents/voice/model.py

@@ -14,7 +14,21 @@ DEFAULT_TTS_INSTRUCTIONS = (
 )
 DEFAULT_TTS_BUFFER_SIZE = 120
 
-TTSVoice = Literal["alloy", "ash", "coral", "echo", "fable", "onyx", "nova", "sage", "shimmer"]
+TTSVoice = Literal[
+    "alloy",
+    "ash",
+    "ballad",
+    "coral",
+    "echo",
+    "fable",
+    "onyx",
+    "nova",
+    "sage",
+    "shimmer",
+    "verse",
+    "marin",
+    "cedar",
+]
 """Exportable type for the TTSModelSettings voice enum"""
 
 

tests/voice/test_tts_voice_types.py

@@ -0,0 +1,7 @@
+from typing import get_args
+
+from agents.voice.model import TTSVoice
+
+
+def test_tts_voice_type_includes_current_openai_builtin_voices() -> None:
+    assert {"ballad", "verse", "marin", "cedar"} <= set(get_args(TTSVoice))