SKILL.md
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If no format is mentioned, just write the .drawio file and open it in draw.io. The user can always ask to export later.
Supported export formats
Format
Embed XML
Notes
png
Yes (-e)
Viewable everywhere, editable in draw.io
svg
Yes (-e)
Scalable, editable in draw.io
pdf
Yes (-e)
Printable, editable in draw.io
jpg
No
Lossy, no embedded XML support
PNG, SVG, and PDF all support --embed-diagram — the exported file contains the full diagram XML, so opening it in draw.io recovers the editable diagram.
draw.io CLI
The draw.io desktop app includes a command-line interface for exporting.
Locating the CLI
First, detect the environment, then locate the CLI accordingly:
#### WSL2 (Windows Subsystem for Linux)
WSL2 is detected when /proc/version contains microsoft or WSL:
grep -qi microsoft /proc/version 2>/dev/null && echo "WSL2"
On WSL2, use the Windows draw.io Desktop executable via /mnt/c/...:
DRAWIO_CMD=`/mnt/c/Program Files/draw.io/draw.io.exe`
The backtick quoting is required to handle the space in Program Files in bash.
If draw.io is installed in a non-default location, check common alternatives:
# Default install path
`/mnt/c/Program Files/draw.io/draw.io.exe`
# Per-user install (if the above does not exist)
`/mnt/c/Users/$WIN_USER/AppData/Local/Programs/draw.io/draw.io.exe`
#### macOS
/Applications/draw.io.app/Contents/MacOS/draw.io
#### Linux (native)
drawio # typically on PATH via snap/apt/flatpak
#### Windows (native, non-WSL2)
"C:\Program Files\draw.io\draw.io.exe"
Use which drawio (or where draw.io on Windows) to check if it's on PATH before falling back to the platform-specific path.
Export command
drawio -x -f <format> -e -b 10 -o <output> <input.drawio>
WSL2 example:
`/mnt/c/Program Files/draw.io/draw.io.exe` -x -f png -e -b 10 -o diagram.drawio.png diagram.drawio
Key flags:
-x/--export: export mode
-f/--format: output format (png, svg, pdf, jpg)
-e/--embed-diagram: embed diagram XML in the output (PNG, SVG, PDF only)
-o/--output: output file path
-b/--border: border width around diagram (default: 0)
-t/--transparent: transparent background (PNG only)
-s/--scale: scale the diagram size
--width/--height: fit into specified dimensions (preserves aspect ratio)
-a/--all-pages: export all pages (PDF only)
-p/--page-index: select a specific page (1-based)
Opening the result
Environment
Command
macOS
open <file>
Linux (native)
xdg-open <file>
WSL2
cmd.exe /c start "" "$(wslpath -w <file>)"
Windows
start <file>
WSL2 notes:
wslpath -w <file>converts a WSL2 path (e.g./home/user/diagram.drawio) to a Windows path (e.g.C:\Users\...). This is required becausecmd.execannot resolve/mnt/c/...style paths.
- The empty string
""afterstartis required to preventstartfrom interpreting the filename as a window title.
WSL2 example:
cmd.exe /c start "" "$(wslpath -w diagram.drawio)"
File naming
- Use a descriptive filename based on the diagram content (e.g.,
login-flow,database-schema)
- Use lowercase with hyphens for multi-word names
- For export, use double extensions:
name.drawio.png,name.drawio.svg,name.drawio.pdf— this signals the file contains embedded diagram XML
- After a successful export, delete the intermediate
.drawiofile — the exported file contains the full diagram
XML format
A .drawio file is native mxGraphModel XML. Always generate XML directly — Mermaid and CSV formats require server-side conversion and cannot be saved as native files.
Basic structure
Every diagram must have this structure:
<mxGraphModel adaptiveColors="auto">
<root>
<mxCell id="0"/>
<mxCell id="1" parent="0"/>
<!-- Diagram cells go here with parent="1" -->
</root>
</mxGraphModel>
- Cell
id="0"is the root layer
- Cell
id="1"is the default parent layer
- All diagram elements use
parent="1"unless using multiple layers
XML reference
For the complete draw.io XML reference including common styles, edge routing, containers, layers, tags, metadata, dark mode colors, and XML well-formedness rules, fetch and follow the instructions at:
https://raw.githubusercontent.com/jgraph/drawio-mcp/main/shared/xml-reference.md
Troubleshooting
Problem
Cause
Solution
draw.io CLI not found
Desktop app not installed or not on PATH
Keep the .drawio file and tell the user to install the draw.io desktop app, or open the file manually
Export produces empty/corrupt file
Invalid XML (e.g. double hyphens in comments, unescaped special characters)
Validate XML well-formedness before writing; see the XML well-formedness section below
Diagram opens but looks blank
Missing root cells id="0" and id="1"
Ensure the basic mxGraphModel structure is complete
Edges not rendering
Edge mxCell is self-closing (no child mxGeometry element)
Every edge must have <mxGeometry relative="1" as="geometry" /> as a child element
File won't open after export
Incorrect file path or missing file association
Print the absolute file path so the user can open it manually
CRITICAL: XML well-formedness
- **NEVER include ANY XML comments (
<!-- -->) in the output.** XML comments are strictly forbidden — they waste tokens, can cause parse errors, and serve no purpose in diagram XML.
- Escape special characters in attribute values:
&amp;,&lt;,&gt;,&quot;
- Always use unique
idvalues for eachmxCell