uml.singsk.com PlantUML

com.singskPublished by singsk.comOfficial publisherv1.1.0.2Updated Oct 28, 2026

Render, validate, encode/decode PlantUML diagram-as-code; 22 diagram types. Free, no auth.

VerifiedStreamable HTTPWeb executableDeveloper ToolsMedia & Design

Overview

AI-generated overview

Remote PlantUML server that lets an assistant render, validate, encode and decode diagram-as-code source across 22 diagram types.

What you can do
  • Render PlantUML source into a PNG image or SVG text, with a shareable render URL
  • Validate source without rendering and get line, column and hint details for fixing errors
  • Encode source into share/render URL tokens, and decode tokens or existing PlantUML URLs back to source
  • List the 22 supported diagram types and fetch a render-verified syntax reference for each
When to use it
Useful when an assistant needs to produce or check UML and other PlantUML diagrams, or to run a generate, validate, fix loop before rendering. Also handy for recovering source from an existing PlantUML URL.
Requirements
Remote streamable HTTP endpoint; no authentication, environment variables or headers declared. Network access to the service is required.
Before you install
Diagram source is sent to a third-party service, so avoid embedding secrets or confidential content in diagrams. Share URLs only work while the encoded token stays within the stated size limit; render instead when the tool reports the URL is not usable.

Installation

In SourceWeft

  1. Open uml.singsk.com PlantUML in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/com.singsk%2Fuml-plantuml/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "uml-singsk-com-plantuml": {
      "type": "http",
      "url": "https://uml.singsk.com/mcp"
    }
  }
}

Tools

6

render_diagram

Render PlantUML source text to a diagram image. Returns a PNG image block (format "png") or the SVG markup as text (format "svg", default), plus the shareable render URL. The source is validated first: on a syntax error the result is an error object with line, column, hint and a help link so you can fix the diagram and retry.

Parameterstextrequiredformat

validate_diagram

Check PlantUML source without rendering. Returns {ok:true, diagram_type} or {ok:false, error:{code, message, line, column, source_line, hint, diagram_type_detected, help}}. Cheap - call it in a generate -> validate -> fix loop before rendering.

Parameterstextrequired

encode_source

Encode PlantUML source into a URL token and ready-to-use share/render URLs (svg + png). The result carries url_ok: GET URLs only work while the token is at most 16000 characters; when url_ok is false do not share the URLs - render with render_diagram instead (it uses the POST API, no size limit up to 5 MB). Tokens use PlantUML's own 64-character alphabet ("0-9 A-Z a-z - _") over raw DEFLATE. This is NOT base64 - never encode or decode tokens with a base64 codec; use encode_source / decode_token.

Parameterstextrequired

decode_token

Recover the PlantUML source from a token or from any PlantUML render URL (the token is extracted automatically). Tokens use PlantUML's own 64-character alphabet ("0-9 A-Z a-z - _") over raw DEFLATE. This is NOT base64 - never encode or decode tokens with a base64 codec; use encode_source / decode_token.

Parametersencodedrequired

list_diagram_types

List the 22 supported diagram/reference types with a one-line description and the local syntax reference URL for each. Use it to pick the right @start directive.

Takes no parameters.

get_syntax_reference

Get the syntax reference entry for one diagram type: description, a render-verified example, and the help page URL. Use it to ground diagram generation.

Parameterstyperequired

Version history

1
  1. v1.1.0.2LatestSep 16, 2026

Score

72% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts

    Publish an icon in the registry entry.

  • Documentation15 pts

    Declare a GitHub repository with a README, or serve resource_documentation in the OAuth protected-resource metadata.

  • LicenseNot applicable

    A hosted service is used under its provider's terms, so no license is expected here. This check is left out of the percentage.