anthropics/jacobian-lens

This issue identifies a critical gap in the `jacobian-lens` library: the absence of a swap-intervention implementation. While the package provides read-side functionality, researchers attempting to replicate causal results from the associated interpretability paper must re-implement core intervention hooks. This significantly increases the barrier to entry for research replication, undermining the library's stated purpose as companion code. The proposed contribution offers a tested solution, highlighting a clear need for robust, complete tooling in AI interpretability. Market implications include slower research progress and reduced adoption of interpretability methods if foundational tools require extensive custom development for basic experimental setups.