Working model · 3D
Mechanistic Interpretability · Causal methods
Where the answer forms
A real 0.5B language model read mid-computation by two lenses, the model's own last step and one trained per layer, and then changed by patching to see where the answer is actually made.Two lenses decode a model's middle layers into words. A 3D dissection of Qwen2.5-0.5B where it writes one token: the tuned lens is far closer to the model than the logit lens, but on 90 pre-registere…