draw-io
Sunwood-ai-labs/draw-io-skillCreate, edit, export, and review draw.io diagrams. Use for native .drawio XML generation, PNG/SVG/PDF export, SVG overlap, border-overlap, label-intrusion, label-rect, short-terminal, and text-overflow linting, layout adjustment, and AWS icon usage.
SKILL.md
name: draw-io description: Create, edit, export, and review draw.io diagrams. Use for native .drawio XML generation, PNG/SVG/PDF export, SVG overlap, border-overlap, label-intrusion, label-rect, short-terminal, and text-overflow linting, layout adjustment, and AWS icon usage.
draw.io Diagram Skill
1. Purpose
Use this skill when an agent needs to:
- create a new draw.io diagram as native
.drawioXML - edit or refactor an existing
.drawiofile - export diagrams to
png,svg,pdf, orjpg - check routed edges, box- or frame-border overlap, supported non-rect shape border overlap, box penetration, short arrowhead tails, label collisions, or text overflow
- build architecture diagrams with AWS icons
This skill intentionally combines:
- the native draw.io assistant workflow used by Claude Code style tools
- practical XML editing and layout rules from repository use
- repository-ready SVG linting that catches issues draw.io does not flag
1.1 Repository structure
The repository layout and bundled workflow pieces are summarized in the diagram below.

The repository also ships:
- an English structure source and exports under
assets/draw-io-skill-structure.drawio* - an icon block showcase under
assets/draw-io-skill-structure-icons.drawio*plus a Japanese-localized companion underassets/draw-io-skill-structure-icons.ja.drawio* - a shape-focused lint review sample under
assets/draw-io-skill-structure-shapes.drawiowith exports atassets/draw-io-skill-structure-shapes.drawio.pngandassets/draw-io-skill-structure-shapes.drawio.svg - a Japanese-localized companion source and exports under
assets/draw-io-skill-structure.ja.drawio* - public showcase pages under
docs/guide/showcase.mdanddocs/ja/guide/showcase.md - fixture-based lint coverage under
fixtures/basic,fixtures/border-overlap,fixtures/large-frame-border-overlap,fixtures/shape-border-overlap,fixtures/label-rect-overlap,fixtures/text-cell-overflow, andfixtures/shape-text-overflow
1.2 Repository-local commands
When working inside this repository, these are the main maintenance commands:
npm install
npm run check
npm run verify
npm ci
npm run docs:build
npm run docs:dev
uv run python -m py_compile scripts/find_aws_icon.py
Use them this way:
npm run check: script syntax plus fixture-based lint verificationnpm run verify: full repository signoff, including docs buildnpm run docs:build: one-shot docs buildnpm run docs:dev: interactive docs preview
If you need to attach the repo as a skill in a local assistant environment, the repository docs use these conventions:
- Codex on Windows: junction
C:\Users\YOUR_NAME\.codex\skills\draw-io -> D:\Prj\draw-io-skill - Claude Code: clone under
~/.claude/skills/drawio
1.3 Repository QA model
The repository uses three QA layers:
- syntax checks for the JavaScript tools
- fixture-based lint verification
- documentation build validation for the public-facing docs
That keeps the technical tooling and the user-facing docs aligned in CI.
2. Default Workflow
Follow this order unless the user asks for something narrower:
- Create or update the native
.drawiofile first. - Keep
.drawioas the editable source of truth for repository work. - If the user asked for an exported artifact, export to
.drawio.png,.drawio.svg,.drawio.pdf, or.drawio.jpg. - If edge routing or label density matters, export SVG and run the lint script.
- Open or surface the final artifact requested by the user.
- Even when lint passes, visually verify the result.
If the user only asks for a diagram and does not request a format, stop at the .drawio file.
3. Basic Rules
- Edit only
.drawiofiles directly. - Do not manually edit generated
.drawio.png,.drawio.svg, or.drawio.pdffiles. - Prefer native mxGraphModel XML over Mermaid or CSV conversions.
- Keep source diagrams unless the user explicitly wants embedded-only cleanup after export.
- Use descriptive lowercase filenames with hyphens.
Examples:
login-flow.drawiologin-flow.drawio.pnger-diagram.drawio.svgarchitecture-overview.drawio.pdf
4. Output Formats
| Format | Embedded XML | Recommended use |
|---|---|---|
.drawio |
n/a | Editable source diagram |
png |
Yes | Docs, slides, chat attachments |
svg |
Yes | Docs, scalable output, lint input |
pdf |
Yes | Review and print |
jpg |
No | Last-resort lossy export |
For repository workflows, prefer:
.drawiowhile editing.drawio.svgwhen running lint.drawio.pngor.drawio.svgfor documentation embeds
5. Export Commands
5.1 Preferred export helper
Use the bundled helper first:
node scripts/export-drawio.mjs architecture.drawio --format png --open
node scripts/export-drawio.mjs architecture.drawio --format svg
node scripts/export-drawio.mjs architecture.drawio --output architecture.drawio.pdf
What it does:
- locates the draw.io CLI on Windows, macOS, or Linux
- uses embedded XML for
png,svg, andpdf - defaults to transparent 2x PNG export
- supports explicit
--drawio <path>when automatic CLI discovery fails - supports optional
--delete-sourcewhen the user explicitly wants only the embedded export
If draw.io CLI discovery fails, rerun with an explicit executable path:
node scripts/export-drawio.mjs architecture.drawio --drawio "C:\\Program Files\\draw.io\\draw.io.exe" --format svg
On macOS or Linux, point --drawio at the installed executable for that environment.
5.2 Manual draw.io CLI export
If needed, call draw.io directly:
drawio -x -f png -e -s 2 -t -b 10 -o architecture.drawio.png architecture.drawio
drawio -x -f svg -e -b 10 -o architecture.drawio.svg architecture.drawio
drawio -x -f pdf -e -b 10 -o architecture.drawio.pdf architecture.drawio
drawio -x -f jpg -b 10 -o architecture.drawio.jpg architecture.drawio
Key flags:
-x: export mode-f: output format-e: embed diagram XML in png/svg/pdf-o: output file path-b: border width-t: transparent background for PNG-s: scale factor-a: all pages for PDF-p: page index (1-based)
5.3 Legacy PNG helper
For existing shell workflows, the original helper remains available:
bash scripts/convert-drawio-to-png.sh architecture.drawio
6. SVG Linting
After exporting SVG, run the bundled lint:
node scripts/check-drawio-svg-overlaps.mjs architecture.drawio.svg
node scripts/check-drawio-svg-overlaps.mjs fixtures/border-overlap/border-overlap.drawio.svg
node scripts/check-drawio-svg-overlaps.mjs fixtures/large-frame-border-overlap/large-frame-border-overlap.drawio.svg
node scripts/check-drawio-svg-overlaps.mjs fixtures/shape-border-overlap/shape-border-overlap.drawio.svg
node scripts/check-drawio-svg-overlaps.mjs fixtures/label-rect-overlap/label-rect-overlap.drawio
node scripts/check-drawio-svg-overlaps.mjs fixtures/text-cell-overflow/text-cell-overflow.drawio
The lint script currently checks:
edge-edge: edge crossings and collinear overlapsedge-rect-border: lines that run along or visibly overlap a box or large frame borderedge-shape-border: lines that run along supported non-rect shape borders such asdocument,hexagon,parallelogram, andtrapezoidedge-rect: lines penetrating boxesedge-terminal: final arrow runs that are too short after the last bendedge-label: routed lines crossing label text boxeslabel-rect: label text boxes colliding with another box or cardrect-shape-border: box or frame borders that run along those supported non-rect shape borderstext-overflow(width): text likely too wide for its boxtext-overflow(height): text likely too tall for its box
Notes:
- input may be either
.drawioor.drawio.svg - when the input is
.drawio, the checker also reads the companion draw.io geometry solabel-rectand text-fit checks stay aligned with the editable source - text overflow detection is heuristic, not pixel-perfect
- bundled fixtures cover simple box-border overlap, large frame-border overlap, supported non-rect shape border overlap, label-box collisions, text-cell overflow, and shape-aware text overflow
edge-terminal,edge-label, andlabel-rectare heuristic checks intended to catch the common "tiny arrowhead tail", "line through label", and "note card covering a label" draw.io failures seen in repository diagrams- lint passing does not replace visual verification
When investigating findings:
- if
edge-rect-border,edge-shape-border, orrect-shape-borderis intentional, keep the routing obvious, visually review the output, and document the exception in the surrounding workflow - if
edge-terminalfires, add a longer straight segment before the arrowhead or move the last bend farther away from the target - if
edge-labelfires, reroute the edge or move the label so the text keeps clean breathing room - if
label-rectfires, move the note/card/box or shift the label so they no longer partially overlap - if
text-overflowlooks like a false positive, first try widening the box, shortening the label, adding an intentional line break, or setting explicit fonts
7. XML And Layout Rules
7.1 Required XML structure
Every diagram must use native mxGraphModel XML:
<mxGraphModel>
<root>
<mxCell id="0"/>
<mxCell id="1" parent="0"/>
</root>
</mxGraphModel>
All normal diagram cells should live under parent="1" unless you intentionally use container parents.
7.2 Edge geometry is mandatory
Every edge cell must contain geometry:
<mxCell id="e1" edge="1" parent="1" source="a" target="b" style="edgeStyle=orthogonalEdgeStyle;">
<mxGeometry relative="1" as="geometry"/>
</mxCell>
Never use self-closing edge cells.
7.3 Font settings
For diagrams with Japanese text or slide usage, set the font family explicitly:
<mxGraphModel defaultFontFamily="Noto Sans JP" ...>
Also set fontFamily in text styles:
style="text;html=1;fontSize=18;fontFamily=Noto Sans JP;"
7.4 Spacing and routing
- space nodes generously; prefer about 200px horizontal and 120px vertical gaps for routed diagrams
- leave at least 20px of straight segment near arrowheads
- use
edgeStyle=orthogonalEdgeStylefor most technical diagrams - add explicit waypoints when auto-routing produces overlap or awkward bends
- when using large outer frames or swimlanes, keep routed segments off the frame stroke and use the gutter between the frame and child boxes instead
- align to a coarse grid when possible
Example with waypoints:
<mxCell id="e1" style="edgeStyle=orthogonalEdgeStyle;rounded=1;jettySize=auto;" edge="1" parent="1" source="a" target="b">
<mxGeometry relative="1" as="geometry">
<Array as="points">
<mxPoint x="300" y="150"/>
<mxPoint x="300" y="250"/>
</Array>
</mxGeometry>
</mxCell>
7.5 Containers and groups
Do not fake containment by simply placing boxes on top of bigger boxes.
- use
parent="containerId"for child elements - use
swimlanewhen the container needs a visible title bar - use
group;pointerEvents=0;for invisible containers - add
container=1;pointerEvents=0;when using a custom shape as a container
7.6 Japanese text width
Allow roughly 30 to 40px per Japanese character.
<mxGeometry x="140" y="60" width="400" height="40" />
If text is mixed Japanese and English, err on the wider side.
7.7 Backgrounds, frames, and margins
- prefer transparent backgrounds over hard-coded white backgrounds
- inside rounded frames or swimlanes, keep at least 30px margin from the boundary
- account for stroke width and rounded corners
- verify that titles and labels do not sit too close to frame edges
7.8 Labels and line breaks
- use one line for short service names when possible
- use
<br>for intentional two-line labels - shorten redundant wording instead of forcing cramped boxes
7.9 Metadata and progressive disclosure
When appropriate, include title, description, last updated, author, or version.
Split complex systems into multiple diagrams when one canvas becomes dense:
- context diagram
- system diagram
- component diagram
- deployment diagram
- data flow diagram
- sequence diagram
8. AWS Icon Workflow
When working on AWS diagrams:
- use the latest official icon naming where possible
- prefer current
mxgraph.aws4.*icon references - remove decorative icons that do not add meaning
Search icons with:
uv run python scripts/find_aws_icon.py ec2
uv run python scripts/find_aws_icon.py lambda
9. Checklist
- diagram source is a valid
.drawiofile - export filenames use
.drawio.<format>when exported - edge cells contain
<mxGeometry relative="1" as="geometry"/> - fonts are explicit when Japanese text is involved
- no hard-coded white page background unless the user asked for it
- containers have enough internal margin
- edge routing is visually clear and leaves room for arrowheads
- SVG lint passes for routing-heavy diagrams
- no
edge-terminalfindings remain unless a tiny terminal run is intentionally accepted - no
edge-labelorlabel-rectfindings remain - no
edge-rect-borderfindings remain unless a box or frame border overlap is intentionally accepted - no
edge-shape-borderorrect-shape-borderfindings remain unless a supported non-rect border contact is intentionally accepted - no
text-overflow(width)ortext-overflow(height)findings remain - final PNG/SVG/PDF was visually checked
10. Repository Docs
For repo-facing documentation and onboarding:
- README.md
- README.ja.md
- docs/guide/getting-started.md
- docs/guide/workflow.md
- docs/guide/architecture.md
- docs/guide/troubleshooting.md
- docs/ja/guide/getting-started.md
- docs/ja/guide/workflow.md
- docs/ja/guide/architecture.md
- docs/ja/guide/troubleshooting.md
- references/layout-guidelines.en.md
- references/aws-icons.en.md
Docs-specific repo note:
- if GitHub Pages styling breaks after a repo rename, verify the VitePress base still matches
/draw-io-skill/
11. References And Credits
This local version is intentionally a blended skill:
- editing and layout guidance inspired by
softaworks/agent-toolkit - native assistant workflow and export conventions inspired by
jgraph/drawio-mcp - SVG linting and repository-ready QA extensions added in this repository
Referenced repositories and sources: