Diagram

Skill timurgaleev/vibestack/skills/diagram

Render a Mermaid diagram to a self-contained HTML file and a PNG, using the browse shim as the renderer — no heavy diagram toolchain to install.From its SKILL.md

Install

npx -y skills add timurgaleev/vibestack --skill diagram

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

3 things to look at

5 stars5 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.
runs commandsInstructs the agent to run 6 commands, including `mkdir -p "$(dirname "$OUT")"` and 5 more.
fetches URLsInstructs the agent to fetch 1 URL, including https://cdn.jsdelivr.net/npm/mermaid@11/dist/mermaid.min.js.

SKILL.md

2.8 KB, 700 tokens by cl100k_base, as published. Nobody here has run it

When to invoke

Use to turn a description or some Mermaid source into a picture — "draw a diagram", "make a flowchart", "diagram this architecture", "visualize this as a graph".

/diagram — Render a Mermaid diagram

vibestack renders Mermaid by wrapping it in a self-contained HTML page (Mermaid from a CDN) and screenshotting it with the browse shim. No extra toolchain: the HTML opens in any browser even with no shim, and the PNG is produced by the same $B you already use for QA.

1. Get the Mermaid source

If the user gave Mermaid, use it. Otherwise write it from their description (flowchart, sequenceDiagram, erDiagram, classDiagram, gantt, etc.). Pick an output base path (default ./diagram).

2. Write the self-contained HTML

OUT="${OUT:-./diagram}"            # base path; produces $OUT.html and $OUT.png
mkdir -p "$(dirname "$OUT")"
cat > "$OUT.html" <<'HTML'
<!DOCTYPE html><html><head><meta charset="utf-8">
<script src="https://cdn.jsdelivr.net/npm/mermaid@11/dist/mermaid.min.js"></script>
<style>body{margin:0;padding:20px;background:#fff;font-family:system-ui}</style>
</head><body>
<pre class="mermaid">
__MERMAID__
</pre>
<script>mermaid.initialize({startOnLoad:true,theme:'default'});</script>
</body></html>
HTML

Replace the __MERMAID__ placeholder with the actual source (write the file with the Write tool if the diagram has characters awkward for a heredoc).

3. Render to PNG with the shim

if [ -n "${B:-}" ] && [ "$("$B" status 2>/dev/null)" != "BROWSE_NOT_AVAILABLE" ]; then
  "$B" daemon >/dev/null 2>&1 &        # the daemon lets Mermaid finish drawing before capture
  sleep 1
  "$B" chain "goto file://$(cd "$(dirname "$OUT")" && pwd)/$(basename "$OUT").html" "wait 1200" "screenshot $OUT.png"
  "$B" daemon-stop >/dev/null 2>&1 || true
  echo "DIAGRAM: $OUT.png (and $OUT.html)"
else
  echo "DIAGRAM_HTML_ONLY: $OUT.html — open it in a browser (no shim for PNG)"
fi

4. Report

Show the PNG path (and the HTML). If the chain reported an error, the Mermaid likely has a syntax issue — fix the source and re-render.

Notes

Mermaid is the supported format. Excalidraw, DOCX, and multi-page exports are not rendered here — for those, hand the user the HTML or use a dedicated tool.
The HTML is self-contained and offline-friendly except the one CDN script tag; it renders in any modern browser.

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.