The /custom/ layer is a template: in upstream microsoft/BCQuality it stays
empty by default and is meant to be populated only inside a fork or consumer
clone. PR #55 both targeted /custom/ and leaked a new top-level folder.
- skills/write.md: add a fork-precondition guard so authors (human or agent)
confirm they are not in microsoft/BCQuality before scaffolding /custom/ content.
- Guard custom layer workflow: auto-closes upstream PRs that add/modify /custom/
content beyond the template files, with a friendly redirect-to-fork comment.
- Flag new top-level entries workflow: posts an advisory (non-blocking) comment
when a PR introduces an unexpected top-level folder or file for maintainer review.
Both workflows run only on microsoft/BCQuality (never on forks) and read the PR
file list via the API without checking out or executing PR code.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
