What problem does it solve? When Yu-Gi-Oh! card builds fail validation checks or diverge from reference cards, this Skill provides a structured loop to trace the root cause and update the responsible skill files so the same errors do not recur. ## Core Features & Use Cases - SMART Self-Evaluation Loop: A six-step non-negotiable cycle covering card rebuild, mdcheck/catalogcheck/combocheck verification, reference comparison, root-cause analysis, skill file updates, and re-validation. - Trigger-Based Diagnosis: Maps specific failure signals (validation score below threshold, comparison match rate under 50 percent, missing catalog entries) to the exact skill file that needs correction. - Use Case: After building a card that fails combocheck.py, run this loop to determine whether the build workflow, catalog data, or validation rules caused the failure, update that file, and rebuild until all checks pass. ## Quick Start Run the card self-evolution loop on the card that just failed validation and update whichever skill file caused the failure.