Knowledge Signal is an open-source tool that analyzes study notes using TypeSafe AI's Jev model to generate structured knowledge profiles with confidence assessments.
A comprehensive benchmark compares Jev, TypeSafe AI's rubric-conditioned classification model, against Claude Haiku 4.5, Claude Sonnet 5, and OpenJev across ten test suites. Jev achieves 50-116x cost reduction and superior accuracy on core classification tasks, though advantages concentrate in specific architectural domains; Sonnet unexpectedly performs best on narrow tasks but worst on batched multi-question grading.