J++ Lens: Jacobian Filtering Enables More Faithful Workspace Lenses

Kola Ayonrinde, Anthropic Fellows, koayon@gmail.com; Jack Lindsey, Anthropic TL;DR: The J-Lens was proposed to read verbalisable representations from language model activations. We introduce the J++ Lens: an improvement to the J-Lens that enables more faithful readouts across 9–284B models. The J++ Lens filters noisy gradients before they enter the averaged Jacobian. Using the J++ Lens as a drop-in replacement for the J-Lens, we read workspace representations with 55% success on latent variable ...