The official draw.io MCP (Model Context Protocol) server that enables LLMs to create and open diagrams in the draw.io editor.
This repository offers four approaches for integrating draw.io with AI assistants. Pick the one that fits your setup:
| MCP App Server | MCP Tool Server | Skill + CLI | Project Instructions | |
|---|---|---|---|---|
| How it works | Renders diagrams inline in chat | Opens diagrams in your browser | Generates .drawio files, optional PNG/SVG/PDF export or browser URL |
Claude generates draw.io URLs via Python |
| Diagram output | Interactive viewer embedded in conversation | draw.io editor in a new tab | .drawio, .drawio.png / .svg / .pdf, or browser URL |
Clickable link to draw.io |
| Requires installation | No (hosted at mcp.draw.io) |
Yes (npm package) | Copy skill file (draw.io Desktop only for PNG/SVG/PDF export) | No — just paste instructions |
| Supports XML, CSV, Mermaid | XML only | ✅ All three | XML only (native format) | ✅ All three |
| Editable in draw.io | Via "Open in draw.io" button | ✅ Directly | ✅ Directly | Via link |
| Works with | Claude.ai, VS Code, any MCP Apps host | Claude Desktop, any MCP client | Claude Code | Claude.ai (with Projects) |
| Best for | Inline previews in chat | Local desktop workflows | Local development workflows | Quick setup, no install needed |
The MCP App server renders draw.io diagrams inline in AI chat interfaces using the MCP Apps protocol. Instead of opening a browser tab, diagrams appear directly in the conversation as interactive iframes.
The official hosted endpoint is available at:
https://mcp.draw.io/mcp
Add this URL as a remote MCP server in Claude.ai or any MCP Apps-compatible host — no installation required.
You can also run the server locally via Node.js or deploy your own instance to Cloudflare Workers.
Tools:
create_diagram— Renders draw.io XML as an interactive diagram inline in chatsearch_shapes— Searches 10,000+ shapes across all draw.io libraries (AWS, Azure, GCP, P&ID, electrical, Cisco, Kubernetes, UML, BPMN, etc.) by keyword. Returns exact style strings that can be used directly in XML. Use this to find the correct shape before callingcreate_diagram.
Note: Inline diagram rendering requires an MCP host that supports the MCP Apps extension. In hosts without MCP Apps support, the tool still works but returns the XML as text.
The original MCP server that opens diagrams directly in the draw.io editor. Supports XML, CSV, and Mermaid.js formats with lightbox and dark mode options. Published as @drawio/mcp on npm.
Quick start: npx @drawio/mcp
A Claude Code skill that generates native .drawio files, with optional export to PNG, SVG, or PDF (with embedded XML so the exported file remains editable in draw.io) — or a browser URL that opens the diagram directly in app.diagrams.net. No MCP setup required — just copy a skill file.
By default, the skill writes a .drawio file and opens it in draw.io. Mention a format in your request to change the output:
/drawio png .../svg/pdf— exports using the draw.io desktop CLI with--embed-diagram/drawio url ...— compresses the XML with Node.js's built-inzliband opens the result atapp.diagrams.net. No draw.io Desktop needed; the.drawiofile is kept locally as a persistent copy.
An alternative approach that works without installing anything. Add instructions to a Claude Project that teach Claude to generate draw.io URLs using Python code execution. No MCP server, no desktop app — just paste and go.
If you're deploying in an environment with strict data restrictions, here is exactly where diagram data goes for each approach.
No component sends your diagram to a cloud rasterizer. convert.diagrams.net (or
any cloud export endpoint) is not called anywhere in this repository, and there is no
"local dependency missing → fall back to cloud" path. PNG/SVG/PDF export happens only
in the Skill + CLI, which shells out to your locally installed draw.io Desktop CLI
(located via which drawio); if it isn't installed, the .drawio file is kept and
nothing is sent.
| Approach | Diagram leaves the machine? |
|---|---|
MCP App Server — hosted (mcp.draw.io) |
Yes — it is sent to the draw.io server as the MCP request. Self-host instead (below) to keep it local. |
| MCP App Server — self-hosted (local Node or your own Cloudflare) | No — processed by your server and embedded in HTML that renders client-side. |
MCP Tool Server (@drawio/mcp) |
No — carried in the URL #fragment, which browsers do not transmit to the server. |
| Skill + CLI | No — written locally and exported by your local draw.io Desktop CLI. |
By default the servers do not write diagram content to their logs — only request
metadata (method, session, status, timing). The Cloudflare-hosted App Server logs
response bodies only when run with DEBUG=true.
Even when the diagram itself stays local, the rendering loads draw.io's web-app /
viewer code from app.diagrams.net and viewer.diagrams.net by default. These
fetch application code and assets — not your diagram — but they are still outbound
requests. To reduce or remove them:
- App Server: build with the
VIEWER_PATHenvironment variable to inline the viewer instead of loading it fromviewer.diagrams.net. - Tool Server: set the
DRAWIO_BASE_URLenvironment variable to a self-hosted draw.io instance. - Skill + CLI: the opt-in
/drawio urlmode opens the diagram atapp.diagrams.net(hardcoded — noDRAWIO_BASE_URLequivalent). Use the default.drawiooutput or local Desktop export instead if you need to avoid that request.
The diagram is generated by the LLM. If you use a hosted model, the diagram content is produced in that provider's cloud regardless of where this MCP server runs. End-to-end isolation requires a locally hosted model as well.
The only reliable way to confirm a deployment makes no outbound calls is to run it with network egress blocked (or watch the browser's Network tab) and verify it still renders. We recommend this for any strict-isolation deployment.
The draw.io XML generation reference — covering edge routing, containers, layers, tags, metadata, dark mode, style properties, and XML well-formedness — lives in a single canonical file:
All four approaches above use this file as their single source of truth for LLM prompts:
| Approach | How it accesses the reference |
|---|---|
| MCP App Server | Reads the file at startup / build time and includes it in the tool description |
| MCP Tool Server | Reads the file at startup (from repo or bundled copy via prepack) |
| Skill + CLI | References the GitHub raw URL |
| Project Instructions | Users copy its contents into their Claude Project |
When updating XML generation guidance, edit only shared/xml-reference.md — changes propagate to all consumers automatically.
The search_shapes tool is powered by a pre-built index of all draw.io shapes. The index is generated from the live draw.io client (https://app.diagrams.net/js/app.min.js) by running all sidebar palette initializations in Node.js via jsdom and capturing the shape data.
shape-search/search-index.json is committed to the repository and is automatically refreshed on every draw.io release via the Update Shape Search Index GitHub Action — no manual step is required to stay in sync with the latest shapes.
To regenerate the index manually (e.g. when iterating on the generator itself):
cd shape-search
npm install
npm run generate
# Rebuild the MCP App Server worker to embed the updated index
cd ../mcp-app-server
npm run build:workerThe generator fetches app.min.js directly from the public draw.io web app, so no local checkout of the draw.io source is needed.
# MCP App Server
cd mcp-app-server
npm install
npm start
# MCP Tool Server
cd mcp-tool-server
npm install
npm start- draw.io - Free online diagram editor
- draw.io Desktop - Desktop application
- @drawio/mcp on npm - This package on npm
- drawio-mcp on GitHub - Source code repository
- Mermaid.js Documentation
- MCP Specification
- MCP Apps Extension