MCP server by simonkurtz-MSFT
Draw.io MCP Server
A Model Context Protocol (MCP) server for programmatic diagram generation using Draw.io (Diagrams.net). This server generates Draw.io XML directly — no browser extension or Draw.io instance required.
Demo Video
Acknowledgements
This project would not exist in this manner if it weren't for the following repositories and their authors. Thank you!
- Original drawio-mcp-server by Ladislav (lgazo): https://github.com/lgazo/drawio-mcp-server
- Azure icons source (
dwarfered): https://github.com/dwarfered/azure-architecture-icons-for-drawio - VS Code Drawio extension by hediet: https://github.com/hediet/vscode-drawio
Features
- 700+ Azure Architecture Icons — Official Microsoft icons with embedded SVG data, organized into ~20 categories (Compute, Networking, Storage, Databases, AI + ML, Security, and more)
- Basic Shapes — Rectangles, ellipses, diamonds, parallelograms, and other flowchart primitives
- Fuzzy Search — Find shapes by partial name across the entire icon library
- Batch Operations — Create and update multiple cells in a single call for better performance
- Layer Management — Create, list, and organize cells across layers
- Style Presets — Built-in Azure, flowchart, and general color presets
- Multiple Transports — stdio (default) and streamable HTTP
- XML Export — Standard Draw.io XML format compatible with Draw.io desktop and web
Documentation
- Transactional mode design: docs/transactional_mode_design.md
Requirements
- Deno v2.3 or higher
Quick Start
From Source
deno run --allow-net --allow-read --allow-env src/index.ts
MCP Client Configuration
Configure your MCP client (Claude Desktop, VS Code, Codex, etc.) to use the server:
Claude Desktop
Edit claude_desktop_config.json:
- macOS:
~/Library/Application Support/Claude/claude_desktop_config.json - Windows:
%APPDATA%\Claude\claude_desktop_config.json
{
"mcpServers": {
"drawio": {
"command": "deno",
"args": ["run", "--allow-net", "--allow-read", "--allow-env", "/path/to/drawio-mcp-server/src/index.ts"]
}
}
}
VS Code
Add to your VS Code settings or .vscode/mcp.json:
{
"mcpServers": {
"drawio": {
"command": "deno",
"args": ["run", "--allow-net", "--allow-read", "--allow-env", "/path/to/drawio-mcp-server/src/index.ts"]
}
}
}
Zed
In the Assistant settings, add a Context Server:
{
"drawio": {
"command": "deno",
"args": ["run", "--allow-net", "--allow-read", "--allow-env", "/path/to/drawio-mcp-server/src/index.ts"],
"env": {}
}
}
Codex
Edit ~/.codex/config.toml:
[mcp_servers.drawio]
command = "deno"
args = ["run", "--allow-net", "--allow-read", "--allow-env", "/path/to/drawio-mcp-server/src/index.ts"]
For a locally running HTTP transport:
[mcp_servers.drawio]
url = "http://localhost:8080/mcp"
oterm (Ollama)
Edit ~/.local/share/oterm/config.json:
{
"mcpServers": {
"drawio": {
"command": "deno",
"args": ["run", "--allow-net", "--allow-read", "--allow-env", "/path/to/drawio-mcp-server/src/index.ts"]
}
}
}
Configuration
Transport Selection
The --transport flag controls which transports to start. Default is stdio.
| Flag | Description |
| ------------------------ | -------------------- |
| --transport stdio | stdio only (default) |
| --transport http | HTTP only |
| --transport stdio,http | Both transports |
Environment Variables
| Variable | Description | Default |
| ------------------------- | ------------------------------------------------------------------------------------- | ---------- |
| AZURE_ICON_LIBRARY_PATH | Path to Azure icon library XML file (auto-detected from assets/ if unset) | (detected) |
| LOGGER_TYPE | Logger implementation: console or mcp_server | console |
| HTTP_PORT | HTTP server port (CLI --http-port takes precedence) | 8080 |
| TRANSPORT | Transport type: stdio, http, or stdio,http (CLI --transport takes precedence) | stdio |
| SAVE_DIAGRAMS | ⚠️ DEV MODE ONLY — Auto-save diagram XML to ./diagrams/ on export/finish | (disabled) |
Tip: You can create a
.envfile from.env.exampleto configure environment variables locally:cp .env.example .env # Edit .env and uncomment/set SAVE_DIAGRAMS=true or other variablesThe server automatically loads
.envfiles at startup. The.envfile is gitignored and won't be committed to the repository.
Development Mode — Auto-save Diagrams
⚠️ WARNING: DEVELOPMENT MODE ONLY — NOT FOR PRODUCTION USE
For local debugging and development, you can enable automatic saving of diagram XML to a local diagrams/ folder. This is useful for inspecting generated diagrams without manually copying XML output.
To enable:
export SAVE_DIAGRAMS=true
deno task start
or
SAVE_DIAGRAMS=true deno task start
Behavior when enabled:
- Every call to
export-diagramorfinish-diagramautomatically saves the XML to./diagrams/<timestamp>_<tool-name>.drawio - Timestamp format:
YYYYMMDD_HHMMSS(e.g.,20260219_143052_export-diagram.drawio) - The
diagrams/folder is created automatically if it doesn't exist - Errors during file saving are logged but do not fail the tool operation
To disable (default):
Simply unset the environment variable or set it to any value other than true or 1:
unset SAVE_DIAGRAMS
or
export SAVE_DIAGRAMS=false
Security note: This feature is disabled by default and should never be enabled in production or containerized deployments. It is intended solely for local development and debugging.
HTTP Transport
The HTTP transport exposes a streamable HTTP endpoint at /mcp (default port 8080).
deno task start:http
# or with a custom port:
deno run --allow-net --allow-read --allow-env src/index.ts --transport http --http-port 4000
MCP client configuration for HTTP:
{
"mcpServers": {
"drawio": {
"command": "deno",
"args": [
"run",
"--allow-net",
"--allow-read",
"--allow-env",
"/path/to/drawio-mcp-server/src/index.ts",
"--transport",
"http",
"--http-port",
"4000"
]
}
}
}
Health check: curl http://localhost:8080/health
Docker
The Docker image uses deno compile to produce a self-contained native binary, then runs it on a minimal distroless base image (~20MB) with no shell, no package manager, and a non-root user.
Pulling from Docker Hub
A pre-built image is available on Docker Hub. This is the fastest way to get started — no cloning or building required.
1. Pull the latest image:
docker pull simonkurtzmsft/drawio-mcp-server:latest
2. Start the container:
docker run -d --name drawio-mcp-server -p 8080:8080 simonkurtzmsft/drawio-mcp-server:latest
This starts the server in the background, exposing the HTTP transport on port 8080.
3. Verify the server is running:
curl http://localhost:8080/health
You should receive an OK response, confirming the server is healthy and ready to accept connections.
4. Point your MCP client to the running container. For example, in VS Code (.vscode/mcp.json):
{
"mcpServers": {
"drawio": {
"url": "http://localhost:8080/mcp"
}
}
}
Or in Claude Desktop (claude_desktop_config.json):
{
"mcpServers": {
"drawio": {
"url": "http://localhost:8080/mcp"
}
}
}
5. To stop and remove the container:
docker stop drawio-mcp-server
docker rm drawio-mcp-server
Building Locally
To build the image from source instead of pulling from Docker Hub:
# Build
docker build -t drawio-mcp-server .
# Run (exposes HTTP on port 8080)
docker run -d --name drawio-mcp-server -p 8080:8080 drawio-mcp-server
Docker Compose
cp .env.example .env # Configure REGISTRY and IMAGE_VERSION
docker compose up -d
The .env file supports:
REGISTRY— Docker registry URL (e.g.,docker.io/myusername)IMAGE_VERSION— Semantic version for image tags (e.g.,1.0.0)
Note: The distroless image has no shell, so in-container health checks (wget, curl) are not available. Use external health checks (e.g., Kubernetes liveness probes, load balancer health checks) to monitor the
/healthendpoint.
Tools
Performance tip: All cell-manipulation tools accept arrays — pass ALL items in a single call rather than calling a tool repeatedly.
Stateless contract: Diagram tools are stateless per call. Pass the full prior
diagram_xmlinto each diagram-related tool call, and carry forward the returneddiagram_xmlfrom the response for the next call.
Shape Discovery
| Tool | Description |
| ------------------------ | -------------------------------------------------------------------------------------------- |
| search-shapes | Fuzzy search for shapes including 700+ Azure icons. Pass all queries in the queries array. |
| get-shape-categories | List all shape categories (General, Flowchart, Azure categories). |
| get-shapes-in-category | List all shapes in a category by category_id. |
| get-style-presets | Get built-in style presets (Azure colors, flowchart shapes, edge styles). |
Diagram Modification
| Tool | Description |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------------------- |
| add-cells | Add vertices and/or edges. Supports shape_name for icon resolution, temp_id for within-batch references, and dry_run validation. |
| edit-cells | Update vertex cell properties (position, size, text, style). |
| edit-edges | Update edge properties (text, source, target, style). |
| set-cell-shape | Apply library shape styles to existing cells. |
| delete-cell-by-id | Remove a cell (vertex or edge) by ID. Cascade-deletes connected edges for vertices. |
Diagram Inspection
| Tool | Description |
| ------------------- | ------------------------------------------------------------- |
| list-paged-model | Paginated view of all cells with filtering by type. |
| get-diagram-stats | Statistics about cell counts, bounds, and layer distribution. |
| export-diagram | Export the diagram as Draw.io XML. |
| import-diagram | Import a Draw.io XML string, replacing the current diagram. |
| clear-diagram | Clear all cells and reset the diagram. |
Layer Management
| Tool | Description |
| -------------------- | -------------------------------------- |
| list-layers | List all layers with IDs and names. |
| set-active-layer | Set the active layer for new elements. |
| create-layer | Create a new layer. |
| move-cell-to-layer | Move a cell to a different layer. |
Page Management
| Tool | Description |
| ----------------- | ---------------------------------------------------------------- |
| create-page | Create a new page (tab) in the diagram. |
| list-pages | List all pages with IDs and names. |
| get-active-page | Get the currently active page. |
| set-active-page | Switch to a different page. |
| rename-page | Rename an existing page. |
| delete-page | Delete a page and all its contents. Cannot delete the last page. |
Group / Container Management
| Tool | Description |
| ------------------------ | ---------------------------------------------------------------------- |
| create-groups | Create group/container cells for VNets, subnets, resource groups, etc. |
| add-cells-to-group | Assign cells to groups. |
| remove-cell-from-group | Remove a cell from its group, returning it to the active layer. |
| list-group-children | List all cells contained in a group. |
Add Cells Example
Use add-cells with temp_id references to create vertices and edges in a single call:
{
"cells": [
{
"type": "vertex",
"temp_id": "web",
"x": 100,
"y": 100,
"width": 60,
"height": 60,
"text": "Web",
"style": "aspect=fixed;html=1;image;image=img/lib/azure2/compute/Container_Instances.svg;"
},
{
"type": "vertex",
"temp_id": "api",
"x": 220,
"y": 100,
"width": 60,
"height": 60,
"text": "API",
"style": "aspect=fixed;html=1;image;image=img/lib/azure2/compute/Container_Instances.svg;"
},
{ "type": "edge", "source_id": "web", "target_id": "api", "text": "HTTPS" }
]
}
Azure Icon Library
The server includes 700+ official Azure architecture icons from dwarfered/azure-architecture-icons-for-drawio, organized into categories:
| Category | Examples | | ----------------------- | --------------------------------------------------------------------- | | AI + Machine Learning | Cognitive Services, Azure OpenAI, Bot Service, Machine Learning | | Analytics | Synapse Analytics, Databricks, Data Factory, Event Hubs | | App Services | App Service, Static Web Apps | | Compute | Virtual Machines, Functions, AKS, Container Instances, Batch | | Containers | Container Registry, Container Instances, AKS | | Databases | SQL Database, Cosmos DB, Cache for Redis, PostgreSQL | | DevOps | Azure DevOps, Pipelines, Repos | | Identity | Azure AD, Key Vault | | Integration | Service Bus, Logic Apps, API Management, Event Grid | | Management + Governance | Monitor, Automation, Policy, Log Analytics | | Networking | Front Door, Load Balancer, Application Gateway, VPN Gateway, Firewall | | Security | Sentinel, Security Center | | Storage | Storage Account, Blob Storage, File Storage, Disk Storage |
Icons use embedded base64 SVG data — no external dependencies, works fully offline with correct Azure branding and colors.
The library loads lazily on first access (singleton pattern). Search operations are <5ms after initial load.
Development
Setup
git clone https://github.com/simonkurtz-MSFT/drawio-mcp-server.git
cd drawio-mcp-server
No install step needed — Deno resolves dependencies on first run.
Common Commands
| Command | Description |
| ------------------------- | ------------------------------------ |
| deno task start | Start with stdio + HTTP transports |
| deno task start:http | Start with HTTP transport only |
| deno task dev | Watch mode — auto-restart on changes |
| deno task test | Run tests |
| deno task test:watch | Run tests in watch mode |
| deno task test:coverage | Run tests with coverage |
| deno task bench | Run focused performance benchmarks |
| deno task lint | Lint and type-check |
| deno task fmt | Format code |
| deno task fmt:check | Check formatting without writing |
| deno task compile | Compile to a self-contained binary |
MCP Inspector
Use the MCP Inspector to debug the server:
deno task inspect
After making changes, Restart the Inspector. After changing tool definitions, Clear and List the tools again.
Related Approaches
Note: The comparisons below are all as of February 2026. Both projects and the agent skill continue to evolve — check their repositories for the latest state.
This project is a fork of lgazo/drawio-mcp-server by Ladislav Gazo. The original acts as a bridge to a live Draw.io instance via a WebSocket browser extension for interactive, real-time diagram control. This fork is a standalone XML generator — it builds diagrams in memory and outputs Draw.io XML without needing a browser or Draw.io instance. thomast1906/github-copilot-agent-skills takes yet another approach: a Copilot Agent Skill that constructs raw Draw.io XML and sends it to the hosted mcp.draw.io service, guided by prompt instructions and a static Azure icon catalog.
| Aspect | simonkurtz-MSFT | Original (lgazo) | Agent Skill (thomast1906) |
| -------------------------------- | ------------------------------------------------------ | ------------------------------------------------------ | --------------------------------------------------- |
| Architecture | Standalone MCP server — generates XML in memory | Bridge to live Draw.io via WebSocket browser extension | Copilot Agent Skill + hosted mcp.draw.io endpoint |
| Runtime | Deno (TypeScript) | Node.js + pnpm (TypeScript + JavaScript) | None (prompt-driven) |
| Draw.io instance required | ❌ | ✅ Browser + MCP extension | ❌ (uses hosted endpoint) |
| Setup effort | Clone + Deno, or docker pull | npx + browser extension + open Draw.io | Drop SKILL.md + catalog into repo |
| Batch operations | ✅ Arrays in add-cells, edit-cells, etc. | ❌ One tool call per cell | ✅ Full XML in one shot |
| Azure icons | ✅ 700+ embedded base64 SVG | ✅ From live Draw.io libraries | ✅ Static catalog (img/lib/azure2/…) |
| Fuzzy shape search | ✅ search-shapes | ❌ Exact name lookup only | ❌ |
| Page management | ✅ | ❌ | ❌ |
| Group / container management | ✅ | ❌ | ❌ |
| Iterative editing | ✅ Stateful model, incremental calls | ✅ Live edits in Draw.io | ❌ Regenerate full XML each time |
| Interactive features | ❌ Stateless XML generation | ✅ get-selected-cell, set-cell-data | ❌ |
| Docker / cloud deployment | ✅ Distroless image (~20 MB) | ❌ npm package only | ❌ Relies on hosted endpoint |
| Offline support | ✅ Fully offline | ⚠️ Needs browser with Draw.io | ❌ Requires internet |
| Best for | CI/CD, containers, headless / offline batch generation | Interactive diagramming with real-time visual feedback | Quick one-shot diagrams with zero install |
All three approaches are valid — the right choice depends on whether you need interactive visual feedback (original), headless batch generation (this fork), or a zero-install agent skill.
