diff --git a/vllm/v1/engine/processor.py b/vllm/v1/engine/processor.py index 96e89eeac556..38d43717b950 100644 --- a/vllm/v1/engine/processor.py +++ b/vllm/v1/engine/processor.py @@ -260,10 +260,10 @@ def _validate_structured_output(self, params: SamplingParams) -> None: else: # NOTE: engine_level_backend must be "auto" here, because we have # checked supported_backends above. - # "auto" is an opt-in to opinionated behavior where we try to - # choose a backend based on request contents. This is not the - # default as it is less predictable and subject to change - # between releases as feature support changes. + # In this mode, we set opinionated defaults based on what we think + # will satisfy the most use cases without having to worry about + # this setting. We include fallback behavior here, but not with any + # other setting where a specific backend was specified. try: validate_xgrammar_grammar(params) params.guided_decoding.backend = "xgrammar"