diff --git a/vllm/sampling_params.py b/vllm/sampling_params.py
index ffedaf596a5c7..f4dce4eecf41e 100644
--- a/vllm/sampling_params.py
+++ b/vllm/sampling_params.py
@@ -152,6 +152,9 @@ def __init__(
         self.min_tokens = min_tokens
         self.logprobs = logprobs
         self.prompt_logprobs = prompt_logprobs
+        # NOTE: This parameter is only exposed at the engine level for now.
+        # It is not exposed in the OpenAI API server, as the OpenAI API does
+        # not support returning only a list of token IDs.
         self.detokenize = detokenize
         self.skip_special_tokens = skip_special_tokens
         self.spaces_between_special_tokens = spaces_between_special_tokens