Does not work with the new LM Studio Bionic...

#66
by cosmingurau - opened

I really had high hopes for this, because the regular Gemma 4 12B is very hit and miss with its tool call, but this seems to be quite worse... maybe I am doing something wrong?

Hi @cosmingurau β€” you're almost certainly hitting a client-side template problem, not a weights problem.

Gemma 4 emits tool calls as custom native tokens (<|tool_call>, <|channel>thought). LM Studio renders templates with minja, which doesn't handle this template β€” so those tokens leak into the output as plain text and the call never fires. koboldcpp and Cline have the same issue. It affects stock Gemma 4 too; it just looks worse here, because this fine-tune emits a lot more tool calls, so there's a lot more to leak.

The one setup I know parses them correctly is llama.cpp's own server, which uses a native PEG parser instead of a template engine:

llama-server -m <your.gguf> -a gemma -c 16384 -ngl 99 -fa on --jinja

--jinja is the critical flag β€” without it you get the same leaked text. That gives you an OpenAI-compatible endpoint on :8080 with proper structured tool_calls, which you can point any client at.

Worth saying: this model is tuned for multi-turn agentic loops, so single-shot "call this tool once" prompting isn't where it's strongest. But leaked tool tokens is a different problem, and that one's fixable on your side. Let me know if it persists after --jinja.

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