j-rig — Skill Refiner

Overview

The Skill Refiner is the eval-guided improvement loop for SKILL.md files. It analyzes an existing skill against measured behavior, proposes safe, minimal, bounded edits, and accepts an edit only when it strictly improves. It is the second product in the Intent Solutions agent-rig stack:

J-Rig Skill Binary Eval   ->   Skill Refiner   ->   Rollout Gate
      (test)                     (improve)             (ship)

The refiner proposes bounded edits (add, delete, or replace operations on the SKILL.md text) and accepts an edit only if a held-out eval score strictly improves with no regression on any other case. It never rewrites a skill wholesale, and it never lets a skill judge itself; scoring is delegated to the separate j-rig eval harness.