The launch arguments had been read from documentation and never from an
engine. Now they have been:
vllm 0.29.0 --host --port --tensor-parallel-size --served-model-name
--distributed-executor-backend all accepted
llama.cpp b10991 --model --host --port --metrics --alias --parallel
--n-gpu-layers all accepted
Getting there found three faults in the checker rather than in llmgw.
It checked every command's flags against the engine's help, but a shard can be
several programs — vLLM under Ray is `ray start` and then `vllm serve` — and
they have different vocabularies. It reported --head and --num-gpus as
missing, which is true of vllm and irrelevant, because ray is what receives
them. Each command is now checked against its own help, and one that cannot be
run is reported as skipped rather than failed.
vLLM does not give up its whole help for --help: it prints a summary of
section names and expects --help=all. Checked against the summary, all five
flags looked missing. The warning about truncated help did not fire, because
the summary happens to mention --help= while listing how to ask for more.
And vLLM refuses to print anything at all on a machine with no accelerator
unless VLLM_TARGET_DEVICE says what to assume. Asking an engine about its
flags should not require the hardware it runs on.
Two things remain unchecked and are written down as such: the Ray sidecar,
because vLLM 0.29 does not install Ray, and SGLang, because it is not
installed anywhere. `launch_mode: mp` avoids Ray entirely and is worth
preferring until someone checks it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
