0/60 Wasn't the Model: The Empty Haystack Behind My Two Worst Corpora

Update — v0.3.1 released. CauterRule is now live on GitHub and PyPI. It turns repeated agent failures into permanent standing rules — extract, replay-test, promote. pip install cauterule gives you the full CLI, framework adapters, rule lifecycle, pack ecosystem, and official rule packs. The v0.3.1 field test report evaluated 2 cloud models across 40 corpora and 4,742 trajectory-runs and is the source for every number below. Release notes · Changelog CauterRule is an open-source sidecar that learns standing rules from repeated agent failures. It extracts lessons from trajectories, replay-tests them, and tries to separate reusable guidance from noisy overgeneralization. Every release, the field test produces a list of worst corpora, and every release the honest first guess is the same: the model can't do this kind of failure. The two worst carried into the v0.3.1 cycle from the v0.3.0 report: adapters — 0/60 on both models, 100% matcher_gap — and raw/ci — 0/110. Both