Markdown Static Site

Use when authoring or reviewing a periodic-scan job that walks every external link in a markdown content set and flags 404s, redirects to unrelated content, and connection failures. Activate this skill whenever the task says 'check our links' or mentions a link-rot scan, broken-link audit, or link-health report. Do NOT use for live runtime link checking inside the rendered page (use a frontend a11y / UX skill) or for chasing a specific broken-link incident from a user report (use debugging).

Use when dispatching a content-fetch task across the multiple sources the site reads from — local markdown under `content/`, MDX with React components under `content/mdx/`, and a headless-CMS sync under `lib/cms/`. Activate this skill whenever the task says 'render this content' or 'where does this post come from' without naming a specific source, or when adding a new source to the routing surface. Do NOT use for the actual rendering of one source (use the per-source skill — `markdown-post-frontmatter-validation`, an MDX rendering skill, or a CMS-sync skill) or for chasing a specific routing bug (use debugging).

Use when migrating every existing post in `content/posts/**/*.md` to the v2 frontmatter schema — adding the new required `summary` field, normalizing `tags` to the controlled vocabulary, converting bare-date `date` strings to ISO 8601 with timezone, and re-validating every post against the v2 schema before the next build runs. Activate this skill whenever the task references migration `0007-frontmatter-v2`, the v2 frontmatter rollout, or asks how to safely change a required-field set across a populated content tree without breaking the build. Do NOT use for unrelated migrations (use a generic content-migration skill or write a fresh one) or for general schema-design questions (use a schema-design skill).

Use when authoring or reviewing the build-time image pipeline config — defining responsive srcset breakpoints, picking output formats (AVIF / WebP / JPEG fallback), tuning compression quality per format, and ensuring the pipeline never produces a lossy artifact for source PNGs with transparency. Activate this skill whenever the task touches `lib/images/pipeline.config.ts`, `scripts/build-images.ts`, or any code path that resizes or recompresses content images. Do NOT use for runtime image rendering choices (use a frontend skill) or for chasing a specific build failure (use debugging).

Use when authoring or reviewing the frontmatter of a markdown post — checking required fields (title, date, slug, tags), validating against the content schema in `lib/content/schema.ts`, catching ambiguous date formats or tags not in the controlled vocabulary, and ensuring the slug matches the file path. Activate this skill whenever the task touches files under `content/posts/**/*.md`, the `parsePostFrontmatter()` helper, or any code path that reads YAML frontmatter from a content file. Do NOT use for general YAML schema design (use a generic schema-design skill) or for chasing a specific build-time validation failure (use debugging).