When it comes to quality of outcome, since at least Feburary, the harness has almost equal, if not more weight than the model itself. It's no longer "which model is the best?" it's "which model + harness is the best?"
I get drastically different tool call failure rates using Claude SDK vs OpenCode using Qwen 3.6 models
I get drastically different tool call failure rates using Claude SDK vs OpenCode using Qwen 3.6 models