What problem does it solve? Keeping multiple README files synchronized with code changes is tedious and error-prone. This Skill automates the process of diffing a branch against main, identifying user-facing API changes, and updating the root README, package README, and namespace READMEs accordingly. ## Core Features & Use Cases - Diff-grounded updates: Runs git log and git diff against main, reads changesets, and builds a list of new, renamed, or removed exports before touching any file. - Multi-level README sync: Handles the root README, packages/gmt/README.md, namespace stub READMEs, and sub-package READMEs with level-specific rules. - Stale reference verification: Greps for renamed or removed function names across all README levels to confirm nothing outdated remains. - Use Case: After adding a new exported function or renaming an existing one in the @northguild/gmt library, run this Skill to propagate the change into every affected README without inventing function names or drifting from established formatting style. ## Quick Start Ask the assistant to update the READMEs to reflect the API changes on the current branch.