md-review — Code-review markdown → 2-column HTML

The code-review converter from Tier 2 of Shihipar's essay ("Code Review and PR Writeups"). Takes a markdown PR writeup with diff blocks + severity callouts and produces a single-file HTML review with a jump-nav, 2-column diff + annotation layout, and a named reviewer footer.

Three stdlib tools pipeline together:

diff_parser.py  →  annotation_extractor.py  →  review_html_renderer.py
   (md → diff hunks)   (md → severity-tagged    (hunks + annotations
                        annotations attached     + tokens → 2-col HTML)
                        to nearest hunk)

When to invoke

Symptom	Action
markdown-html-orchestrator routes input as REVIEW	Invoke this skill
User runs /cs:md-review <path>.md directly	Invoke this skill
Input contains ```diff fenced blocks + > [!MAJOR]/> [!BLOCKER]/etc. callouts	Invoke this skill
Input is a long-form spec / report (no diff blocks)	Route to md-document instead
Input is a slide deck	Route to md-slides instead
Input < 100 lines	Refuse (Shihipar threshold)
Design-system not onboarded	Refuse; surface /cs:design-system

Pipeline

# 1. Parse markdown → diff hunks JSON
python3 markdown-html/skills/md-review/scripts/diff_parser.py \
    --input <path>.md --output hunks.json

# 2. Extract severity-tagged annotations, attach to nearest preceding hunk
python3 markdown-html/skills/md-review/scripts/annotation_extractor.py \
    --input <path>.md --diff-blocks hunks.json --output annotations.json

# 3. Render 2-col HTML (--reviewer is mandatory — refuses without)
python3 markdown-html/skills/md-review/scripts/review_html_renderer.py \
    --diff-blocks hunks.json --annotations annotations.json \
    --reviewer "Jane Doe" --title "PR #123: Add retry logic" \
    --output review.html

What gets rendered

• Top jump-nav — every annotation with severity badge + 80-char preview + jump link; severity counts in the heading ("3 BLOCKER · 2 MAJOR · 1 NIT")
• 2-column hunk rows — unified diff on the left (per-line old/new line numbers, +/− marks, addition/deletion background tint from design-system tokens), annotation cards on the right (color + icon + aria-label per WCAG 1.4.1)
• Approval bar — if LGTM markers are present and no severity annotations, a success-tinted "LGTM — no findings flagged" bar
• General comments — annotations not attached to any hunk render at the bottom in their own section
• Reviewer footer — mandatory; refuses to render without --reviewer
• Responsive — 2-col collapses to stacked on viewports < 900px

Hard rules

1. --reviewer is mandatory. A code review must name a human reviewer. Refuses with exit 3 otherwise. Mirrors research-ops's "named owner" discipline.
2. Refuses if no hunks present. No --- a/file + @@ ... @@ blocks means this isn't a code review — refuses with exit 4 and recommends md-document.
3. Refuses input < 100 lines. Markdown wins below the threshold (Shihipar).
4. Refuses without onboarding. Same gate as every converter.
5. Severity is never color-only. Each badge ships color + icon + aria-label + text. WCAG 1.4.1 enforced at the renderer level.
6. Single-file output. All CSS inline. Only external is Google Fonts CSS. No Prism in md-review (diff coloring conflicts with syntax highlighting).
7. Custom severity convention. --severity-convention "critical,important,suggestion,nit" swaps tier names; position 0 is most severe. Default is BLOCKER / MAJOR / MINOR / NIT (Google Code Review Developer Guide).

Forcing-question library (Matt Pocock grill discipline)

1. Who is the named reviewer? Recommended: the user signing off on the review. Canon: research-ops named-owner pattern; SWE at Google ch. 9.
2. Which severity convention applies — default (BLOCKER/MAJOR/MINOR/NIT) or custom? Recommended: default unless your team has a documented alternative. Canon: Google Code Review Developer Guide.
3. Are annotations anchored to specific hunks, or are some general? Recommended: anchor everything you can; general goes to the unanchored section. Canon: SWE at Google ch. 9 — "Comments must reference a specific line".
4. What's the PR title for the <title> and header? Recommended: the actual PR / commit title. Canon: docs-as-context-for-readers.
5. Should LGTM markers ship as the approval bar? Recommended: yes if there are no severity annotations; otherwise the findings take precedence.

Distinct from

• md-document — that converter renders prose + tables + code + callouts. This one renders diff hunks + margin annotations.
• md-slides — that converter splits on --- boundaries. This one is a single-page artifact.
• GitHub PR comments — those are a thread. This is a single-author snapshot artifact.

Output artifact

{default_output_dir}/review-{slug}.html (path resolved by orchestrator's output_path_resolver.py; collision suffix -2, -3, … by default).

References

• Shihipar — Claude Code HTML output (Medium, 2026), Tier 2 use case
• Software Engineering at Google (Manshreck & Wright, O'Reilly 2020), ch. 9 "Code Review"
• Google Code Review Developer Guide — severity convention source
• WCAG 2.2 §1.4.1 — color-not-sole-signal enforcement
• See references/ for full citations (diff_rendering_canon, severity_coding, pr_annotation_ux)