RubricRefine: Improving Tool-Use Agent Reliability with Training-Free Pre-Execution Refinement

ArXi:2605.09730v1 Announce Type: new Iterative self-refinement is a popular inference-time reliability technique, but its effectiveness in code-mode tool use depends heavily on the structure of the feedback signal: unstructured critique helps inconsistently across models, and even revision with real execution feedback improves only modestly ($0.75$ vs. $0.65$ baseline). The dominant failures are inter-tool contract violations - wrong output shape, incorrect tool routing, broken argument provenance - that run to completion without raising errors, making runtime feedback insufficient. We.