What problem does it solve? Teams often fix a bug, move on, and then hit the same class of bug again because the root cause and prevention lessons were never captured. This Skill performs a structured post-fix analysis that turns one-off debugging into permanent knowledge recorded in project specs. ## Core Features & Use Cases - Root Cause Classification: Categorizes each bug into one of five categories (missing spec, cross-layer contract, change propagation failure, test coverage gap, implicit assumption) with a comparison table. - Failure Retrospective: Analyzes why earlier fix attempts failed, distinguishing surface fixes, incomplete scope, tool limitations, and mental model errors. - Prevention & Knowledge Capture: Produces a prioritized prevention-mechanism table and mandates immediate updates to .trellis/spec/guides/ thinking guides, template syncing, and committing the spec changes. - Use Case: After fixing a bug where an API returned timestamps in seconds instead of milliseconds, run this analysis to classify it as an implicit-assumption bug, document prevention mechanisms, and update the cross-layer thinking guide so the class of bug never recurs. ## Quick Start Analyze the bug we just fixed using the break-loop framework and update the relevant spec guides with the prevention lessons.
