What can you do with this server?

UML-MCP turns text descriptions or diagram source into rendered diagrams directly inside AI chat clients, supporting 46 diagram types (37 via Kroki plus 9 interactive plugins). * Discover types — list_diagram_types finds diagram types by text, backend, or required output format. * Render one diagram — generate_uml returns an image, render URL, editable playground link, and chat-embed markdown. * Inline chat image — generate_uml_image returns MCP ImageContent with a bounded base64 preview (PNG by default). * Validate first — validate_uml checks type, format, and syntax locally, returning errors, warnings, suggestions, and normalized code. * Batch render — generate_uml_batch renders up to 20 diagrams in one call; one failure doesn't stop the rest. * Interactive viewer — in MCP Apps clients, diagrams open in a viewer to zoom, edit source, switch theme/format, re-render, and export. * Re-render & download — rerender_diagram and download_diagram (viewer-only) re-render with a new theme/format and export source, SVG, PNG, PDF, or HTML in chunks. * Styling options — themes (PlantUML, Mermaid, D2, light/dark), scale factor, and formats (svg, png, pdf, jpeg, txt, base64, html).

Which integrations are available for this server?

Generates Excalidraw diagrams as part of the supported specialized diagram types, rendered via Kroki. Generates Mermaid diagrams as part of the supported diagram types, rendered via Kroki.

How do I use UML-MCP?

1. Click on "Deploy Server". 2. Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state. 3. In the chat, type @ followed by the MCP server name and your instructions, e.g., "@UML-MCP Draw a UML sequence diagram for user registration" That's it! The server will respond to your query, and you can continue using it as needed. Here is a step-by-step guide with screenshots.

UML-MCP

by antoinebou12

Overview Schema Source Related Servers Discussions Admin

Python

Hybrid

UML-MCP

Diagrams for AI assistants. A Model Context Protocol server that turns a description or diagram source into a rendered diagram, inside the chat.

Docs · Quick start · Interactive diagrams · Changelog · Contributing

It works as an MCP App

In clients that support MCP Apps, diagrams open in a viewer inside the chat (ui://uml-mcp/diagram-viewer): zoom, edit the source, switch theme and format, re-render, step through a batch, and export SVG, PNG, HTML or PDF. Clients without MCP Apps get the same diagram as an inline PNG and SVG.

Related MCP server: Draw.io MCP Server

Why UML-MCP

46 diagram types. 37 through Kroki (UML, Mermaid, D2, Graphviz, C4, BPMN, ERD, TikZ...) and 9 interactive ones: cloud and stack diagrams with real logos, archify-style architecture, workflow and sequence diagrams, and 2D/3D LLM visualisations.
Shows up in the chat. Every client gets an inline image plus links to the rendered file and an editable playground. Clients with MCP Apps also get an interactive viewer.
Ready to run. Hosted endpoints, or local with Docker or Helm; optional Entra ID / OAuth 2.1 SSO, audit logs and metrics. It scores 95/100 on the Manufact publishing checklist.

Quick start

Add the hosted server to your MCP client:

"uml-mcp": {
  "transport": "http",
  "url": "https://uml-mcp.vercel.app/mcp"
}

Then ask, for example, "Draw a sequence diagram of a user logging in through an API gateway."

Endpoint	URL
Primary (Vercel)	`https://uml-mcp.vercel.app/mcp`
Mirror (Manufact)	`https://uml-mcp.antoineboucher.info/mcp`

Ready-made configs: Cursor · VS Code / Copilot · Codex · Claude Desktop · Open WebUI · all clients. To run it yourself:

uv tool install uml-mcp && uml-mcp setup

The installation guide covers Docker, Helm and running from source.

Interactive diagrams

These plugins ship with UML-MCP and are on by default. Each type renders to an interactive HTML The plugins below ship with UML-MCP and are on by default. Each type renders to an interactive HTML page in the viewer and to a static SVG and PNG everywhere else.

Plugin	Types	What you get
D3	`d3_force` · `d3_architecture` · `d3_topology`	Force graphs and cloud diagrams with real provider and brand logos, routed with A*
Stack diagram	`stack_diagram`	Icon tiles, nested vendor and region groups, numbered request steps
Archify	`archify_architecture` · `archify_workflow` · `archify_sequence`	Colour-coded groups, legend, three presets, click to focus and trace the shortest path
LLM visualizer	`llm_2d` · `llm_3d`	Layer maps, autoencoder and GAN shapes, `N×` blocks and a rotatable 3D scene
Database schema	`db_schema`	ER diagrams from SQL DDL or JSON: column cards, crow's-foot keys at the column rows, search
Dependency graphs	`dependency_graph`	A project's dependency tree from `package.json`, `pyproject.toml`, `requirements.txt` or a lock file
Statechart	`state_machine`	XState-like machines as statecharts, and a simulator that fires events, with a step log and Undo
Agent traces	`agent_trace`	An agent run as a waterfall and a flow: LLM, tool and retrieval steps with tokens, cost, retries and the critical path
C4 model	`c4_model`	One model, three C4 levels: click a system to open its containers, a container for its components
Timeline	`timeline`	Roadmaps with swimlanes, phases, milestones, releases and dependency arrows; zoom from quarters to days

{
  "title": "SaaS stack",
  "groups": [{"id": "vercel", "name": "Vercel", "icon": "vercel"}],
  "nodes": [
    {"id": "user", "name": "User", "icon": "user"},
    {"id": "web", "name": "Next.js", "icon": "browser", "group": "vercel"},
    {"id": "db", "name": "Neon", "icon": "database"},
    {"id": "ci", "name": "GitHub Actions"}
  ],
  "edges": [
    {"from": "user", "to": "web", "label": "HTTPS", "step": 1},
    {"from": "web", "to": "db", "label": "SQL", "step": 2},
    {"from": "ci", "to": "web", "label": "deploy", "style": "dashed"}
  ]
}

Send that as stack_diagram and you get the GitHub and Vercel logos, two numbered steps and a dashed deploy edge. The plugins guide has example prompts for every type and shows how to write your own.

Tools

Tool	Purpose
`generate_uml`	Render one diagram: image, URL and playground link
`generate_uml_image`	The same as an inline chat image (PNG by default)
`validate_uml`	Check source before rendering; errors say how to fix it
`list_diagram_types`	The live catalog, including plugin types
`generate_uml_batch`	Many diagrams in one call

Resources (uml://types, uml://examples, uml://templates...), prompts and skills (skill://uml-mcp-diagrams/SKILL.md plus focused guides) are listed in the reference.

Documentation

Topic	Where
Getting started and tutorials	Tutorials
Diagram types and notation	Diagram types
Clients, Docker, Helm, Vercel	Deploy
MCP App viewer and publishing	MCP App
Configuration (`uml-mcp.yaml`)	Configuration
Enterprise SSO, audit, metrics	Enterprise
Plugins	Plugins
Admin console	Admin

Development

uv sync --all-groups
uv run pytest
uv run ruff check . && uv run ty check
uv run uml-mcp lint --strict --min-grade A

About 1,800 tests, including browser tests of every interactive page inside the MCP App viewer. See Testing and CONTRIBUTING.md.

License

MIT. Maintained by Antoine Boucher. Built on PlantUML, Kroki, Mermaid, D2 and D3. Brand logos come from LobeHub Icons (MIT) and remain trademarks of their owners.

Available Tools

7 tools

download_diagramDownload DiagramC

Read-onlyIdempotent

Download source, SVG, PNG, PDF or HTML chunks. Repeat sha256 on follow-ups.

Inputs: code (required), diagram_type (required), theme, offset, +2 more. Returns: chunk, total, offset, sha256, +3 more

generate_umlGenerate DiagramB

Idempotent

Render diagram source into an image. Returns url (render link), playground (source editor), display_markdown (chat embed), content_base64/mime_type when bytes are fetched and local_path for a saved file. Prefer SVG in MCP Apps.

Inputs: code (required), diagram_type (required), scale, theme, +2 more. Returns: Structured output for diagram generation tools. The first MCP Apps response is…

generate_uml_batchGenerate Diagram BatchA

Idempotent

Render several diagrams in one call; a failed item does not stop the others. Inline previews share one 48k budget; later items load when opened.

Inputs: items (required), output_dir. Returns: Structured output for generate_uml_batch.

generate_uml_imageGenerate Diagram ImageA

Idempotent

Render a diagram as MCP ImageContent for chat with a bounded inline preview. Returns content_base64, mime_type, render and playground links. Fetches bytes even under URL-only. Large images use a PNG thumbnail in MCP Apps.

Inputs: code (required), diagram_type (required), scale, theme, +1 more. Returns: Structured output for diagram generation tools. The first MCP Apps response is…

list_diagram_typesList Diagram TypesA

Read-onlyIdempotent

Find types by text, backend or format. Returns diagram_type keys with backend, description and formats.

Inputs: limit, query, backend, output_format. Returns: Dynamic diagram type map returned by list_diagram_types.

rerender_diagramRe-render DiagramA

Read-onlyIdempotent

Render the viewer’s diagram source again with the selected theme and format. Returns content_base64, mime_type, url, playground, and display_markdown. Hidden from the model; callable from ui://uml-mcp/diagram-viewer via tools/call.

Inputs: code (required), diagram_type (required), scale, theme, +1 more. Returns: Structured output for diagram generation tools. The first MCP Apps response is…

validate_umlCheck Diagram SourceA

Read-onlyIdempotent

Validate diagram type, format, and syntax locally (no render). Returns valid, errors, warnings, suggestions, and diagnostics; prepared_code is normalized source and changes explains normalization. Set strict=true for extra Mermaid/D2 checks.

Inputs: code (required), diagram_type (required), strict, output_format. Returns: Structured output for validate_uml.

Tool Schema Changelog

Recent tool additions, removals, and schema changes observed during successful MCP inspections.

Loading tool schema changelog…

Deploy Server

Claude Code, inside the Godot 4 editorFlockbay puts an AI agent in the real Godot 4 editor: it writes GDScript, runs your game and fixes what breaks. Free, or bring your own Claude Code or Codex.flockbay.comAd

TDQS

A3.7/5.0

Scored 2026-11-05 12:55 across 7 tools

Disambiguation4/5

Most tools target distinct steps in the diagram workflow: listing types, validating, generating, batch rendering, rerendering, and downloading. The main overlap is between generate_uml, generate_uml_image, and generate_uml_batch, which all render diagrams but differ by output channel or multiplicity; descriptions clarify this, though an agent could still hesitate.

Naming Consistency4/5

All names use snake_case with a verb-first pattern (generate_uml, validate_uml, download_diagram, list_diagram_types, rerender_diagram). The generate_uml / generate_uml_image / generate_uml_batch family varies in specificity, but the convention remains predictable.

Tool Count5/5

Seven tools is well-scoped for a UML/diagram rendering server, with each tool covering a distinct part of the workflow. There is no obvious padding or missing operational layer.

Completeness5/5

The surface covers diagram type discovery, local validation, single and batch rendering, UI rerendering, and multi-format download. No major lifecycle gap is apparent for the stated rendering and validation purpose.

Maintenance

ActivityActive

ResponsivenessLimited data

Resources

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io.github.mskry
Generate cloud architecture diagrams, flowcharts, and sequence diagrams.
Software Architecture Design Tools Cloud Platforms
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https://diagrams-mcp-production.up.railway.app/mcp
uml.singsk.com PlantUMLA
com.singsk
Render, validate, encode/decode PlantUML diagram-as-code; 22 diagram types. Free, no auth.
Software Architecture Developer Tools
61
https://uml.singsk.com/mcp
Apricot
tools.apricot
Manage SysML2 projects; check, evaluate, verify, query, document and diagram models.
Developer Tools File Systems
1
https://mcp.apricot.tools/
MBEstudioB
com.vectorstreamsystems
SysML v2 systems engineering: generate, verify, simulate and export system models from text.
Software Architecture Developer Tools
311
https://studio.vectorstreamsystems.com/mcp

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UML-MCP

It works as an MCP App

Why UML-MCP

Quick start

Interactive diagrams

Tools

Documentation

Development

License

Available Tools

Tool Schema Changelog

TDQS

Maintenance

Resources

Related MCP Connectors

Related MCP Servers

MCP-GLSP

Draw.io MCP Server

MCP Documentation Server

staruml-mcp