Agent skill

HTML Over Markdown

by happycapy-ai in happycapy-ai/Happycapy-skills

Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity.

MITAuto-check passedDocuments & Office

Install HTML Over Markdown

skills CLI
$ npx skills add happycapy-ai/Happycapy-skills --skill html-over-markdown -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install happycapy-ai/Happycapy-skills html-over-markdown --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/happycapy-ai/Happycapy-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/html-over-markdown .claude/skills/html-over-markdown && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
html-over-markdown
GitHub stars
137
Token cost
~1.7k tokens
SKILL.md length
807 words
Files
6 (incl. references, assets)
Skills in repo
28
Repo updated
First seen
Licence
MIT

At a glance

Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity.

  • Works in 6 steps: Identify the scenario from the 5… → Read the matching section in… → Pull reusable snippets from… → …
  • Implementation plans
  • SKILL.md covers Why this exists, When to use vs. skip, Workflow and The 5 scenarios, plus 3 more sections
  • Calls python

What it does

HTML Over Markdown is an agent skill from happycapy-ai/Happycapy-skills. Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity. Use for specs, implementation plans, side-by-side design comparisons, PR writeups and code explainers, research and status and incident reports, slide decks, SVG flowcharts, and throwaway editors like triage boards, feature-flag editors, and prompt tuners. Prefer this skill whenever the user asks for a report, plan, or explainer they'll actually want to read — even if they don't…

Its SKILL.md is about 1.7k tokens, which your agent loads only when the skill is triggered. The skill folder holds 7 other files, including reference files and assets (for example `references/design-language.md`, `references/playbook.md` and `references/principles.md`).

It sits in Documents & Office, covering Diagrams, Markdown and Slides and decks. The repository describes itself as: A curated collection of high-quality Claude Code skills to enhance your development workflow. The licence is MIT.

When your agent uses it

  • Implementation plans
  • Side-by-side design comparisons
  • PR writeups and code explainers
  • Research and status and incident reports

Example prompts

  • “ll actually want to read — even if they don”
  • “/html-over-markdown”

Requirements

  • Python 3

Workflow steps

6 steps, taken from the first numbered list in SKILL.md.

  1. Identify the scenario from the 5 families in the table below.
  2. Read the matching section in references/playbook.md for patterns and a prompt template.
  3. Pull reusable snippets from references/snippets.md (grids, diffs, SVG, sliders, export buttons).
  4. Start from assets/base-template.html — it has the default style already wired up. Copy it, then fill in.
  5. Write the result to ./outputs/.html and declare it in the block as outputs/.html`.
  6. Only if the HTML needs a real server (e.g., fetch, complex event handlers that fail on file://), run python -m http.server 8080…

What it can do on your machine

Read from SKILL.md and the folder at commit 9ff72fe. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    Shell commands in SKILL.md call:

    • python

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

HTML Over Markdown loads about 1.7k tokens when it runs, and up to ~11k if it reads all its reference files. Until then it costs about 138 tokens; SKILL.md has 807 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~138
When it runs · the whole SKILL.md, loaded when a task matches
~1.7k
With references · SKILL.md plus every file in references/, read only if the agent opens them
~11k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from happycapy-ai/Happycapy-skills at commit 9ff72fe, republished under its MIT licence (© happycapy-ai). 807 words, ~1,651 tokens.

Download SKILL.mdSave it as .claude/skills/html-over-markdown/SKILL.md (or your agent's skills folder). This skill also uses 5 other files; get the full folder from GitHub.
name
html-over-markdown
description
Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity. Use for specs, implementation plans, side-by-side design comparisons, PR writeups and code explainers, research and status and incident reports, slide decks, SVG flowcharts, and throwaway editors like triage boards, feature-flag editors, and prompt tuners. Prefer this skill whenever the user asks for a report, plan, or explainer they'll actually want to read — even if they don't explicitly say "HTML".

HTML Over Markdown

Produce a single self-contained .html file as the primary output format instead of Markdown.

Why this exists

Markdown flattens spatial information — diffs, dependency graphs, side-by-side comparisons — into linear text. It has no color, no diagrams, no interaction, and people rarely read past ~100 lines. HTML trades a document the user would skim for one they would actually read.

Concrete wins over Markdown:

  • Information density: tables, SVG, CSS, scripts, images — all in one file
  • Visual clarity: tabs, collapsible sections, responsive layout, typographic hierarchy
  • Sharing: one link, any browser, no special viewer
  • Two-way interaction: sliders, toggles, editors, and a copy-back-to-prompt loop
  • Expressiveness: no more ASCII diagrams or unicode color approximations

When to use vs. skip

Use this skill when the user asks for:

  • A spec, plan, proposal, brainstorm, or multi-option exploration
  • A PR writeup, code review, or code/feature explainer
  • A report — status, research, incident, weekly
  • A side-by-side comparison of designs, approaches, or benchmarks
  • A slide deck or visual walkthrough
  • A throwaway interactive editor (triage board, feature flags, prompt tuner)
  • Anything they'd "actually want to read" — even without the word HTML

Do NOT use this skill when:

  • The deliverable is a real .pdf / .docx / .pptx / .xlsx file → use those skills
  • The user wants a production web app (multi-file React/Vue/Next) → use frontend-design or artifacts-builder
  • The spec is Git-tracked and teammates need clean diffs → keep Markdown
  • The user wants a poster or visual artwork → use canvas-design
  • The answer is a one-paragraph reply → just answer

If unsure, read references/principles.md → "What this skill is NOT for".

Workflow

  1. Identify the scenario from the 5 families in the table below.
  2. Read the matching section in references/playbook.md for patterns and a prompt template.
  3. Pull reusable snippets from references/snippets.md (grids, diffs, SVG, sliders, export buttons).
  4. Start from assets/base-template.html — it has the default style already wired up. Copy it, then fill in.
  5. Write the result to ./outputs/<descriptive-kebab-case>.html and declare it in the <attachments> block as <file type="static">outputs/<name>.html</file>.
  6. Only if the HTML needs a real server (e.g., fetch, complex event handlers that fail on file://), run python -m http.server 8080 --directory outputs and /app/export-port.sh 8080. For plain static pages, skip this.

The 5 scenarios

#ScenarioTypical triggerSignature patterns
1Spec, Planning & Exploration"Help me plan…", "explore approaches…", "compare options"Side-by-side grid, labeled tradeoffs, mockups, data-flow SVG
2Code Review & PR"Explain this PR", "review this code", "help onboard a reviewer"Annotated diff with margin notes, severity chips, module graph
3Design & Prototype"Design system", "component variants", "prototype an animation"Variant matrix, color swatches, tunable sliders + Copy-as-CSS
4Report, Research & Explainer"Status report", "explain how X works", "incident writeup"TL;DR, collapsible sections, tabbed samples, SVG diagrams, timeline
5Custom Editor"Let me reorder…", "tune this config", "edit this prompt with live preview"Drag-drop or forms, live preview, required: Copy-as-{JSON,Prompt,Markdown} button

Open references/playbook.md and jump to the matching scenario for full patterns, structural templates, and prompt seeds.

Show full SKILL.md (325 more words)Show less

The 5 principles (keep these in mind throughout)

  1. Self-contained: one .html, all CSS/JS/SVG inline. CDN links are OK; build steps are not.
  2. SVG, never ASCII: any diagram — flow, sequence, architecture, dependency — must be SVG.
  3. Spatial, not linear: if you'd use a bullet list for it in Markdown, think again. Options go in a grid, diffs go inline with margins, dependencies go in a graph.
  4. Export-to-prompt: any interactive control must have a button that writes something to the clipboard (JSON, Markdown, or a natural-language prompt) so the loop closes back into Claude Code.
  5. Readable at a glance: responsive, quiet palette, obvious hierarchy. Optimize for "opens file → understands in 10 seconds".

Full rationale, reasoning, and the default style blueprint are in references/principles.md.

Default style and output conventions

The default aesthetic is Anthropic warm-editorial — ivory #FAF9F5 background, clay #D97757 as the single accent, serif headings with mono uppercase eyebrows, 1.5px warm-gray borders. Full tokens, typography, and signature patterns live in references/design-language.md — read it before producing output.

The starter template in assets/base-template.html has the full palette wired up (--ivory, --clay, --oat, --olive, --rust, warm grays --g100…--g700, serif/sans/mono stacks, h1 with <em> in clay, callouts with clay stripe, mono chips).

Prefer adapting this template over writing new CSS from scratch. If the user references a design system of their own, mirror its tokens. If they ask explicitly for Anthropic brand styling, optionally combine with brand-guidelines.

File naming: ./outputs/<descriptive-kebab-case>.html. Pick a name that would make sense six months later — rate-limiter-explainer.html, not output.html.

A note on philosophy

The author of the underlying methodology deliberately warned against turning this into a rigid /html template skill, because the knowing-when-and-what matters more than the generation mechanics. This skill honors that: it teaches decision-making and patterns, bundles copy-paste snippets rather than generators, and trusts you to compose. Don't over-engineer — most of the time, the right move is to start from the base template, pick a scenario pattern, and write the thing.

© happycapy-ai, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 5 other files (references, assets) in skills/html-over-markdown of happycapy-ai/Happycapy-skills.

  • SKILL.md
  • assets/base-template.html
  • references/design-language.md
  • references/playbook.md
  • references/principles.md
  • references/snippets.md

Open the folder on GitHubat commit 9ff72fe

Compare with similar skills

HTML Over Markdown next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

HTML Over Markdown compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
HTML Over Markdown this skillhappycapy-ai/Happycapy-skills137—~1.7kAutomated safety check: PassMIT
Ky Markdown RebuilderKyrieCheungYep/ky-markdown-rebuilder117—~5.7kAutomated safety check: PassNone
Smalldocs Authorespressoplease/smalldocs209—~1.1kAutomated safety check: PassCustom licence
PPTX To Mdsammcj/agentic-coding162—~1.8kAutomated safety check: PassApache-2.0
Visualizedisplay-dev/visualize136—~7.4kAutomated safety check: PassMIT
Markvisgeekplux/markvis1.6k—~786Automated safety check: PassMIT

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Questions about HTML Over Markdown

What does HTML Over Markdown do?

Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity. HTML Over Markdown is an agent skill from happycapy-ai/Happycapy-skills. Generate rich, self-contained HTML documents instead of Markdown when output needs visual hierarchy, diagrams, or interactivity.

When should I use HTML Over Markdown?

HTML Over Markdown fits situations like: implementation plans; side-by-side design comparisons; PR writeups and code explainers; research and status and incident reports.

How do I install HTML Over Markdown in Claude Code?

Run `npx skills add happycapy-ai/Happycapy-skills --skill html-over-markdown -a claude-code`. Or copy the skill folder (skills/html-over-markdown in happycapy-ai/Happycapy-skills) into .claude/skills/html-over-markdown in your project. Claude Code loads it when a task matches its description.

How do I install HTML Over Markdown in Codex?

Run `npx skills add happycapy-ai/Happycapy-skills --skill html-over-markdown -a codex`. Or copy the skill folder (skills/html-over-markdown in happycapy-ai/Happycapy-skills) into .agents/skills/html-over-markdown in your project. Codex loads it when a task matches its description.

Can I use HTML Over Markdown in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add happycapy-ai/Happycapy-skills --skill html-over-markdown -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/html-over-markdown, .gemini/skills/html-over-markdown, .github/skills/html-over-markdown and .opencode/skills/html-over-markdown in your project.

What does HTML Over Markdown need to run?

Going by SKILL.md and its folder, HTML Over Markdown needs the command-line tools its instructions call (python). Our summary lists: Python 3.

Does HTML Over Markdown access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is HTML Over Markdown safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does HTML Over Markdown use?

HTML Over Markdown is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does HTML Over Markdown use?

About 1.7k tokens (SKILL.md is roughly 6.6k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 9.4k tokens, read only when the agent opens those files.

What are the alternatives to HTML Over Markdown?

Skills that share tags, products or a category with HTML Over Markdown: Ky Markdown Rebuilder (KyrieCheungYep/ky-markdown-rebuilder, 117 stars), Smalldocs Author (espressoplease/smalldocs, 209 stars), PPTX To Md (sammcj/agentic-coding, 162 stars) and Visualize (display-dev/visualize, 136 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains HTML Over Markdown?

happycapy-ai (a GitHub user) maintains it in happycapy-ai/Happycapy-skills, which has 137 GitHub stars. The repository holds 28 skills in this directory. The repository was last updated on September 3, 2026.

Source: happycapy-ai/Happycapy-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.