Drop a 9B open-weight model into an agent system built for a frontier cloud model and accuracy falls from 96.0% to 62.3% on PinchBench. Same task. Same tools.

Drop a 9B open-weight model into an agent system built for a frontier cloud model and accuracy falls from 96.0% to 62.3% on PinchBench. Same task. Same tools. Retune the system around the local model. Change the quantization, reasoning loop, tool access, and memory. Accuracy recovers to 88.4%, clo…