REDDIT · REDDIT// 9d agoMODEL RELEASE

Jackrong drops Qwopus3.5-27B-v3 for steadier tool use

Qwopus3.5-27B-v3 is a Hugging Face model release from Jackrong built on Qwen3.5-27B, with a focus on reasoning stability, tool-calling reliability, and cleaner intermediate reasoning. The discussion around it is mostly about getting it to run under vLLM: the base Qwen3.5 family is supported by vLLM, but this specific checkpoint appears to need tokenizer/config adjustments, and the community report shows a startup error tied to the tokenizer class plus a follow-up warning about incorrect regex handling.

// ANALYSIS

Hot take: this looks promising as an agent-oriented 27B reasoning model, but it is not a smooth out-of-the-box vLLM experience yet.

–The model is explicitly positioned for structured reasoning and tool use, not just raw chat quality.
–vLLM supports Qwen3.5 in general, so the architecture is not the blocker.
–The reported failure is a repo-specific integration issue: `TokenizersBackend` is not recognized by vLLM 0.18.1.
–A workaround mentioned in the discussion is changing `tokenizer_class` to `Qwen2Tokenizer` and enabling `fix_mistral_regex`, but that still did not restore tool calling for the reporter.
–Best read: this is a useful model for local agent workflows, but serving it in vLLM likely needs template/tokenizer cleanup rather than a simple `vllm serve` command.

// TAGS

qwen3.5qwenreasoningtool-callingvllmhuggingfacelocal-llm27b

DISCOVERED

9d ago

2026-04-03

PUBLISHED

9d ago

2026-04-03

RELEVANCE

8/ 10

AUTHOR

beginor