Md Document

Markdown Document Publishing

Turn an authored markdown file into a single HTML document you can email, host,

or print — semantic structure, an automatic table of contents, figures and

tables numbered and referenceable by number, footnotes, and a print stylesheet

that survives contact with a PDF exporter. One file out, no runtime dependencies,

no external assets.

When to use this skill

• Publishing a report or whitepaper that must arrive as one file, not a folder
• Producing a PDF from markdown without a LaTeX or Pandoc toolchain
• Numbering figures and tables so prose can reference them instead of saying "below"
• Converting untrusted or contributed markdown where injection safety matters
• Standardizing a document series so every issue looks like the same publication
• Catching broken cross-references before a document reaches readers

Inputs the skill expects

• A markdown source file, optionally with YAML frontmatter
• Figure images as relative paths (or data URIs, for true single-file output)
• The intended output: screen, print, or both
• Document length and whether a table of contents is warranted
• Page geometry, if printing: size, margins, single- or double-sided
• A stylesheet, if not using the bundled theme

Clarify First

Before converting, confirm these inputs. If any is unknown or vague, ASK — do not assume:

• [ ] Screen, print, or both — why it changes the output: print needs a page profile, forced light colors, and break control; skipping it produces a document that looks right on screen and breaks on paper
• [ ] Whether images must be embedded — why it changes the output: relative image paths mean the HTML file is not actually self-contained, which defeats the point if it will be emailed
• [ ] Document length and TOC expectation — why it changes the output: a TOC on a two-page memo is noise; depth 3 on a long report produces a TOC longer than some sections
• [ ] Whether the markdown is trusted — why it changes the output: it does not change escaping (always on), but it determines whether a review gate should run first

Stop rule: ask only the 2-3 that most change the output. If the user says "just draft it," proceed and list your assumptions at the top of the artifact.

Workflows

Workflow 1 — Convert a document to self-contained HTML

• Audit labels and references first — the converter's gate reports broken

references, but the auditor explains what to do about each one.

• Convert. The bundled theme is inlined automatically; pass --css to override.
• Check the gate. A non-zero exit means the rendered document contains visible

[?fig:name] markers where numbers should be.

python3 markdown-html/md-document/scripts/crossref_auditor.py \
  --input markdown-html/md-document/assets/sample_document.md --format text

python3 markdown-html/md-document/scripts/md_to_html.py \
  --input markdown-html/md-document/assets/sample_document.md \
  --out build/report.html --toc-depth 2 --format text

Workflow 2 — Produce a print-ready PDF

• Generate the print block from a page profile and append it to the theme, so

the exported file carries its own print rules.

• Convert with the extended stylesheet.
• Open in a browser, print to PDF with margins set to Default — a browser

margin setting overrides @page and will clip content.

python3 markdown-html/md-document/scripts/print_profile.py \
  --input markdown-html/md-document/assets/sample_print_profile.json \
  --out build/print.css --format text

cat markdown-html/md-document/assets/document_theme.css build/print.css > build/full.css

python3 markdown-html/md-document/scripts/md_to_html.py \
  --input markdown-html/md-document/assets/sample_document.md \
  --css build/full.css --out build/report.html

Workflow 3 — Gate a document series in CI

• Run the auditor at warning severity so unlabelled figures block, not just

broken references.

• Run the conversion gate; it fails on unresolved references and undefined

footnotes — both render as visible defects.

• Emit JSON for both so a CI job can annotate the diff.

python3 markdown-html/md-document/scripts/crossref_auditor.py \
  --input markdown-html/md-document/assets/sample_document.md --max-severity warning --format json

python3 markdown-html/md-document/scripts/md_to_html.py \
  --input markdown-html/md-document/assets/sample_document.md --out build/report.html --format json

Decision frameworks

Table-of-contents depth

| Document length | TOC | --toc-depth |

|-----------------|-----|---------------|

| Under 3 pages | none — omit [TOC] | n/a |

| 3-10 pages | yes | 1 (## only) |

| 10-30 pages | yes | 2 (default) [PROVEN] |

| Over 30 pages | yes | 2, plus per-section navigation |

If the TOC exceeds one screen, reduce the depth. A contents list longer than the

first section is a navigation failure, not thoroughness.

Reference style

| Situation | Write | Not |

|-----------|-------|-----|

| Pointing at a figure | [@fig:access] | "the chart below" |

| Pointing at a table | [@tbl:policies] | "see the table above" |

| Pointing at a section | [@sec:context] | "as discussed earlier" |

| A caveat that breaks the sentence | a footnote | a parenthetical |

| Evidence the argument depends on | body text | a footnote |

[PROVEN] Never use positional language in a document that may be paginated.

"Below" breaks when the table lands on the next page, breaks silently when a

section is reordered, and means nothing to a reader navigating by heading.

Alt text versus caption

| | Alt text | Caption |

|---|---------|---------|

| Audience | Non-sighted readers | Everyone |

| Length | 15-125 characters | One or two sentences |

| Says | What the image depicts | What to conclude, plus the number |

| Fails as | "chart", "figure 3", "" | "See above" |

The auditor flags placeholder alt text (chart, image, screenshot, empty) at

error severity and alt text under 15 or over 125 characters at warning.

Print geometry

| Decision | Default | Change when |

|----------|---------|-------------|

| Page size | A4 [RECOMMENDED] | Audience is exclusively North American → Letter |

| Side margins | 25-30mm | Never below 20mm — the measure exceeds 90 characters |

| Body size | 11pt | 12pt for older audiences or dense reference material |

| Mirrored margins | off | The document will be bound double-sided |

| break-inside: avoid | figures, tables, code | Never on an element taller than one page |

At A4 with 20mm margins the text column is ~92 characters — well outside the

55-85 comfort band. Widening the margins is the fix; max-width: none on main

is what causes the problem.

Anti-Patterns

The "see the table below" reference

Mistake: Writing positional prose — "the chart below", "as shown above" — instead of a numbered cross-reference.

Why it happens: It reads naturally while drafting, when the author can see the whole document at once and the table genuinely is below.

Instead: Write [@tbl:policies]. Pagination moves content, reordering breaks positional claims silently, and a reader navigating by heading has no "below". The auditor cannot detect a broken "below"; it fails the build on a broken [@tbl:policies].

Allowing raw HTML through the converter

Mistake: Adding an escape hatch so authors can drop <div class="..."> or an embed into the markdown.

Why it happens: A real formatting need appears that the subset does not cover, and passing HTML through is a one-line change.

Instead: Extend the subset or the stylesheet. The escape-then-render ordering is the entire security model — the moment raw HTML passes through, every document becomes an injection vector, and the converter can no longer be pointed at contributed content. There is deliberately no --allow-html flag.

Reusing the caption as alt text

Mistake: Writing one string and letting it serve as both the figure caption and the alt attribute.

Why it happens: The converter falls back to exactly this when no caption is given, which makes it look sanctioned.

Instead: Write both. The caption tells a sighted reader what to conclude; the alt text describes what the figure shows to someone who cannot see it. "Figure 3. Costs fall 40% under Policy B" is a fine caption and useless alt text — it states the conclusion without describing the chart.

Print rules added after the fact

Mistake: Building the document for screen, then bolting on a print stylesheet when someone asks for a PDF.

Why it happens: Print feels like a rendering detail rather than a design constraint, and the screen version already looks finished.

Instead: Decide print-or-not before converting. Retrofitted print CSS produces the classic failures — stranded headings, tables split mid-row, dark theme reaching paper as invisible gray text, a 92-character measure. print_profile.py exists so the geometry is a reviewed input, not an afterthought.

Trusting the gate as a proof of quality

Mistake: Treating a passing conversion as evidence the document is ready to publish.

Why it happens: The gate is automated and green, which reads as authoritative.

Instead: The gate checks that references resolve and footnotes are defined. It cannot see a stranded heading, a figure separated from its caption, a table split across pages, or a PDF whose margins clipped the content. Proof every page of the actual output at 100% zoom before publishing.

Files

| File | Purpose |

|------|---------|

| scripts/md_to_html.py | CLI: convert markdown to a self-contained HTML document; gates on broken references |

| scripts/md_render.py | Markdown subset parser, escaping-first inline renderer, label numbering — imported by md_to_html.py, not a CLI |

| scripts/crossref_auditor.py | Audit labels, references, alt text, and heading hierarchy; CI gate |

| scripts/print_profile.py | Generate a print/PDF stylesheet from a JSON page profile |

| references/markdown-conventions.md | Supported syntax, labelling contract, escaping and URL-allowlist model |

| references/print-and-pdf-production.md | Paged media, break control, export mechanics, proofing checklist |

| assets/sample_document.md | Working document exercising every construct; converts clean |

| assets/sample_print_profile.json | A4 double-sided print profile with running heads |

| assets/document_theme.css | Bundled theme inlined by default — this skill's own copy |

| assets/document_outline_template.md | Starting structure for a new report or memo |

All scripts share one exit-code contract: 0 clean, 2 gate failed (findings at or above the threshold), 1 the tool itself errored. A CI job can therefore tell a real defect from a broken invocation.

Three CLI tools, one module. md_render.py is a library, not a fourth

command — it holds the parser that md_to_html.py imports. A single-file

converter came to 429 lines, well over the 300-line ceiling. Splitting CLI from

parser is the remedy the tool-design standard prescribes for an oversized script,

and same-directory imports keep the package self-contained: md-slides carries

its own separate slide_render.py rather than importing this one.