Gemma certainly was trained for tool calling, but the implementation in llama.cpp has been troubled because Gemma uses a different chat template format. The processor from the transformers library works fine though.

I'm using llama.cpp with Gemma and tool calling is mission critical. It's perfectly fine on my end.

There are definitely differences in the eagerness to tool-call that you'll need to manage. And for all local models I've ever used, I've had to micromanage the tools provided by servers to eliminate any possibility that they reach for something wonky or confusing.

> However I find qwen unbeatable for toolcallling. I think gemma wasnt trained on that at all.

Gemma4 chat template seems to had multiple issues, at least with llama.cpp, not sure they're all fixed yet. It assumed simple types for parameters for example.