diff --git a/vllm/entrypoints/chat_utils.py b/vllm/entrypoints/chat_utils.py
index 41354dc602c61..785dcbfa83119 100644
--- a/vllm/entrypoints/chat_utils.py
+++ b/vllm/entrypoints/chat_utils.py
@@ -166,15 +166,15 @@ def _placeholder_str(self, modality: ModalityStr,
             if model_type == "molmo":
                 return ""
 
-            raise TypeError(f"Unknown model type: {model_type}")
+            raise TypeError(f"Unknown {modality} model type: {model_type}")
         elif modality == "audio":
             if model_type == "ultravox":
                 return "<|reserved_special_token_0|>"
-            raise TypeError(f"Unknown model type: {model_type}")
+            raise TypeError(f"Unknown {modality} model type: {model_type}")
         elif modality == "video":
             if model_type == "qwen2_vl":
                 return "<|vision_start|><|video_pad|><|vision_end|>"
-            raise TypeError(f"Unknown model type: {model_type}")
+            raise TypeError(f"Unknown {modality} model type: {model_type}")
         else:
             raise TypeError(f"Unknown modality: {modality}")