sync‑monorepo‑packages is a CLI (and API) tool that copies selected fields from a source package.json—and any arbitrary files—to the package.json files of all other packages in a monorepo. It auto‑detects packages via npm workspaces or Lerna, supports dry‑run previews, selective package targeting, and custom field/file syncing, making it useful for developers maintaining consistent metadata across many packages in a monorepo.