Draw.io Diagram Skill

Generate draw.io diagrams as native .drawio files and export them to PNG images that can be embedded in Word documents.

How to Create a Diagram

1. Generate draw.io XML in mxGraphModel format for the requested diagram
2. Write the XML to a .drawio file using the create/edit file tool
3. Export to PNG using the bundled export script

Bundled Export Script

This skill includes drawio-to-png.mjs, a Node.js export script with two rendering backends:

1. draw.io CLI (pixel-perfect, fastest) — used automatically if draw.io desktop is installed
2. Official draw.io viewer in headless browser (pixel-perfect, needs Chromium/Edge) — fallback when CLI is unavailable

Usage

# Install dependencies (one-time, from the scripts folder)
cd skills/drawio/scripts && npm install

# Export a single diagram
node skills/drawio/scripts/drawio-to-png.mjs <input.drawio> [output.png]

# Export all .drawio files in a directory
node skills/drawio/scripts/drawio-to-png.mjs --dir <directory>

# Force a specific renderer
node skills/drawio/scripts/drawio-to-png.mjs --renderer=cli|viewer|auto <input.drawio>

Skill Folder Contents

File	Purpose
SKILL.md	This instruction file
scripts/drawio-to-png.mjs	Node.js export script (CLI + browser fallback)
scripts/package.json	Dependencies (puppeteer-core)

Supported Export Formats

Format	Embed XML	Notes
png	Yes	Viewable everywhere, editable in draw.io
svg	Yes	Scalable, editable in draw.io
pdf	Yes	Printable, editable in draw.io

Draw.io XML Style Conventions

Use these styles for consistent, professional diagrams:

<!-- Primary service (highlighted) -->
<mxCell style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;strokeWidth=2;arcSize=12;shadow=1;" />

<!-- External system -->
<mxCell style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f5f5f5;strokeColor=#666666;" />

<!-- Success/processing stage -->
<mxCell style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;" />

<!-- Warning/quality gate -->
<mxCell style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;" />

<!-- Error/failure path -->
<mxCell style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;" />

<!-- Data store (cylinder) -->
<mxCell style="shape=cylinder3;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;" />

<!-- Arrow -->
<mxCell style="edgeStyle=orthogonalEdgeStyle;rounded=1;strokeColor=#6c8ebf;strokeWidth=2;" />

Locating the draw.io CLI

Try drawio first (works if on PATH), then fall back:

• Windows: "C:\Program Files\draw.io\draw.io.exe"
• macOS: /Applications/draw.io.app/Contents/MacOS/draw.io
• Linux: drawio (via snap/apt/flatpak)

CLI Export Command

drawio -x -f png -e -b 10 -o <output.png> <input.drawio>

Flags: -x (export), -f (format), -e (embed diagram XML), -b (border), -o (output path).