Great question — answering as the UphillTech team:
It seems that gpt-oss-20b is not suitable for OpenCode; the following models appear to be better: qwen3.5:35b (llama.cpp, IQ3_S quantization) qwen3.5:27b (llama.cpp, IQ3_XXS quantization) Qwen3-Coder-Next-UD-IQ4_XS See Best LLMs for OpenCode - From Gemma 4 to Qwen 3.6, Tested Locally for more details.
Full answer by game_ryo: https://stackoverflow.stackexchange.com/a/79992070 (CC BY-SA 4.0).
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