---
name: markdown-html-orchestrator
description: Use when a user wants to convert any markdown file in their Claude project into a single-file, lightly-interactive HTML — long-form documents (specs, plans, RFCs, reports, explainers), code reviews...
---

# Markdown → HTML — Domain Orchestrator

Thariq Shihipar's argument (Claude Code HTML output essay, Medium 2026): **markdown collapses past 100 lines for agent-generated artifacts.** Long specs, code reviews, and architecture explainers lose density, hierarchy, and lightweight interaction the moment they exceed a screen of text. HTML restores all three — single-file, browser-native, shareable.

This orchestrator forks context, classifies the input markdown deterministically, routes to the right converter sub-skill, and returns a digest with the output path. Heavy intake (full markdown bodies, diffs, slide decks) stays in the forked context.

**Foundation status (v2.10.0):** orchestrator + `design-system` (onboarding + shared brand tokens) are live. Converter sub-skills (`md-document`, `md-review`, `md-slides`) land in v2.10.1 follow-up PRs. Until they land, this skill still runs the classifier and the design-system gate, and surfaces the routing recommendation — it just hands the rendering work back to Claude with the structured brief.

## When to invoke

| Symptom | Sub-skill |
|---|---|
| "Convert this RFC / spec / report / explainer to HTML" — long-form doc | `md-document` |
| "Turn this PR writeup / code review into HTML" — markdown with diff blocks | `md-review` |
| "Make a slide deck from this markdown" — `---` boundaries or H1 cadence | `md-slides` |

## Pre-flight gates (hard refusals)

1. **Below the 100-line threshold.** Markdown wins below 100 lines (Shihipar). The classifier prints `below_min_lines: true` and `route_explainer.py` refuses. Tell the user to keep their input as markdown.
2. **Design-system not onboarded.** If `~/.config/markdown-html/design-system.json` doesn't exist (or its `setup_completed_at` is null), refuse. Point the user at `python3 markdown-html/skills/design-system/scripts/onboard.py` (or `--defaults` for a zero-touch run).
3. **Unwritable save location.** `output_path_resolver.py` refuses if the configured `default_output_dir` (or `--out` override) isn't writable.

## Routing logic (deterministic)

Two-signal threshold pattern lifted from `research-ops/skills/research-ops-skills/SKILL.md`. Filename hint = 2 points; each content signal = 1 point. Silent-route allowed when winner ≥ 3 AND (runner-up = 0 OR winner ≥ 2× runner-up). Below threshold → one clarifying question with a recommended answer.

### Signal table

| Signal class | Filename hints | Content signals | Sub-skill |
|---|---|---|---|
| DOCUMENT | `report.md`, `*-doc.md`, `spec.md`, `rfc-*.md`, `*-analysis.md`, `*-explainer.md` | `## Table of Contents` (2), `^# `, `^## `, markdown table rows, `> [!NOTE]/[!TIP]/[!IMPORTANT]` callouts | `md-document` |
| REVIEW | `review.md`, `*-pr-*.md`, `*.diff.md`, `code-review*.md` | ` ```diff ` (2), `^[-+]{3} ` (2), `^@@` (2), `> [!BLOCKER]/[!MAJOR]/[!MINOR]/[!NIT]` (2), `LGTM`/`nit:`/`blocker:` | `md-review` |
| SLIDES | `deck.md`, `slides.md`, `*-talk.md`, `presentation*.md` | `^---$` ≥ 3 (2 + per-boundary), `<!-- notes:` (2), H1 count ≥ 5 with median gap ≤ 12 lines (2) | `md-slides` |

The pipeline:

```bash
python3 skills/markdown-html-orchestrator/scripts/doctype_classifier.py \
    --input <path>.md --output json \
  | python3 skills/markdown-html-orchestrator/scripts/route_explainer.py
```

`route_explainer.py` checks the design-system status, applies the < 100-line refusal, and prints one of: `ROUTE_SILENTLY -> md-<type>`, `ASK_USER one question: ...`, or `REFUSE — fix the issues above`.

## Workflow

### Step 1 — Confirm onboarding

If the user has never run onboarding, surface the one-time setup:

```bash
python3 markdown-html/skills/design-system/scripts/onboard.py
```

Ten questions, 1-2 minutes. Captures brand primary + accent + heading/body Google Fonts + design style (editorial/technical/minimal/playful) + default output dir + syntax theme + TOC behavior + optional logo/company. Stored at `~/.config/markdown-html/design-system.json`. Re-runnable with `--scope project` for per-repo overrides.

### Step 2 — Classify the input

Run `doctype_classifier.py` on the markdown. Inspect the verdict.

### Step 3 — Route or ask

Pipe the classification into `route_explainer.py`. If it says `ROUTE_SILENTLY`, forward the original markdown + the design-system config into the named sub-skill's renderer in the forked context. If it says `ASK_USER`, ask ONE question with the recommended answer.

### Step 4 — Resolve the output path

```bash
python3 skills/markdown-html-orchestrator/scripts/output_path_resolver.py \
    --input <path>.md --doctype <document|review|slides>
```

Collision handling defaults to `-2 / -3 / ...` suffix; `--on-collision timestamp` for stamped names.

### Step 5 — Hand off to the sub-skill (when shipped)

In v2.10.1+, the converter sub-skill's renderer takes the input markdown, the design-system config, and the resolved output path, and writes a single self-contained HTML file. The orchestrator returns a ≤ 100-word digest: input lines, output path, design style applied, top 3 features used (TOC, search, code-copy, etc.), and one forcing question for the user.

Until v2.10.1, the orchestrator's job stops at step 4 — it returns the classification + routing brief and lets Claude do the rendering inline with the design-system tokens.

## Forcing-question library (Matt Pocock grill-with-docs pattern)

Walk these one at a time, with a recommended answer per question, citing the canon. Lift this list into `/cs:grill-markdown-html` for plan-stage interrogation.

1. **What decision does this HTML drive — is the reader skimming, deciding, or presenting?**
   Recommended: name it first; density follows from purpose. Canon: Shihipar — "match output format to consumption context"; Tufte — *Visual Display of Quantitative Information*, ch. 1.
2. **Is the input markdown ≥ 100 lines?**
   Recommended: yes — below that, keep it as markdown. Canon: Shihipar — markdown still wins under 100 lines.
3. **Is the design-system onboarded?**
   Recommended: yes, globally (`~/.config/markdown-html/design-system.json`). Canon: research-ops onboarding pattern (`research-ops/CLAUDE.md` §8); WCAG 2.2 §1.4.3 (text contrast 4.5:1).
4. **Where does the output save, and will it overwrite anything?**
   Recommended: the configured `default_output_dir` with `--on-collision suffix`. Canon: Matt Pocock `handoff` skill — never silently overwrite a working artifact.
5. **Document type confidence — silent-route or one question?**
   Recommended: silent-route only when the classifier's verdict is one of `document/review/slides` AND `silent_route_allowed: true`. Otherwise ask. Canon: research-ops two-signal threshold (`research-ops/skills/research-ops-skills/SKILL.md` §"Routing logic").

Never run a sub-skill before the lane is locked.

## Assumptions

1. User has a markdown file ≥ 100 lines they want to convert.
2. User has run onboarding once (`~/.config/markdown-html/design-system.json` exists with `setup_completed_at` populated).
3. Single-file HTML output is acceptable (no multi-file site, no embedded server, no build step).
4. Externals limited to Google Fonts CSS + Prism.js CDN (jsdelivr / cdnjs).

## Non-goals

- Not a landing-page generator (use `marketing/landing/`).
- Not an interactive prompt-tuning playground (use Anthropic's official `playground` plugin).
- Not a static-site generator (no multi-file output, no site index).
- Not a PDF generator (slides use `@media print`; user prints from browser).
- Not a watch / live-reload pipeline (conversion is one-shot).

## Distinct from

- **Anthropic Playground plugin** (`/playground`) — builds interactive controls (sliders, knobs, drag-drop) for prompt tuning, with a copy-prompt-back loop. This plugin converts existing markdown documents to HTML. Different tools for different jobs.
- **`marketing/landing/`** — generates landing pages from scratch (Phase-0 intake → 3 sections → branded TSX/HTML). This plugin converts an existing markdown file you already have.
- **`engineering/handoff/` + `productivity/handoff/`** — preserve session continuity between Claude conversations. Different artifact type (handoff brief vs. document conversion).

## Output artifacts

| Sub-skill | Artifact | Status |
|---|---|---|
| `md-document` | `doc-<slug>.html` (single file, sticky TOC, collapsibles, search, code-copy, scrollspy) | v2.10.1 |
| `md-review` | `review-<slug>.html` (2-col diff + severity margin notes + jump-nav) | v2.10.1 |
| `md-slides` | `deck-<slug>.html` (arrow-key nav + presenter mode + print-to-PDF) | v2.10.1 |

## Anti-patterns (do not)

- ❌ Convert markdown < 100 lines — markdown still wins. Refuse and tell the user.
- ❌ Run the orchestrator before the design-system is onboarded. The output looks broken without tokens.
- ❌ Silently chain two sub-skills (e.g., "convert doc AND make slides from it"). Pick one, finish, ask before chaining.
- ❌ Use external JS frameworks (React/Vue/Svelte). Vanilla JS + IntersectionObserver only. Prism.js CDN is the single exception.
- ❌ Multi-file output (extracted CSS, asset directories). Single file or nothing — that's the whole point.
- ❌ Overwrite an existing output file by default. The path resolver suffixes `-2`, `-3`, …; `--on-collision overwrite` is opt-in only.

## References

- Spec: Thariq Shihipar — "Claude Code HTML output" (Medium, 2026)
- Forking pattern: `research-ops/skills/research-ops-skills/SKILL.md` (`context: fork`, two-signal routing)
- Customization pattern: `research-ops/skills/clinical-research/scripts/` (`onboard.py`, `config_loader.py`)
- Brand palette math: `marketing/landing/skills/landing/scripts/brand_palette_validator.py` (WCAG + HSL derive)
- Information-density canon: Tufte; Shihipar's `thariqs.github.io/html-effectiveness/` gallery; Wattenberger interactive essays; Maggie Appleton digital gardens