Ball: AI coding tools must optimize harness and scaffolding per model
Thorsten Ball · Amp: The Emperor Has No Clothes · Sep 25, 2025 · at 24:45
Thorsten Ball (lead on Sourcegraph's Amp coding agent) argues that model selector dropdowns are ineffective without custom scaffolding for each model.
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“And people are now also waking up to the fact that it's not just the model, it's the system prompt, it's the tools, it's the harness. The scaffolding around the model. So I can give you the choice to use Gemini 2.5 in, in AMP, but without the system prompting you into it without, you know, what I call before, like going with the grain of the model, the models are trained in different ways. So you want to optimize the tool and all around it for this specific model. Without that happening, it doesn't make a lot of sense.”
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