How could the harness fix this? It's the jinja template used by the inference engine to render the API requests into the raw text that gets tokenized and completed by the model. Unless you're using something like the raw completions API instead of the `/v1/chat/completions` API, and effectively applying the template yourself. In which case, you could also just modify the jinja template on your server.

Anyhow, I've heard mixed results on any method of supplying reasoning traces beyond the current turn to models not trained on them. For some models, I've heard that it works fine this way, for others I've heard it degrades performance. But I don't know of anyone who has any kind of reliable benchmark for how well this works.