Zovo Class Diagram

UML class diagrams from plain text.

Zovo Class Diagram turns a short text description of classes into a UML class diagram. Write each class with its fields and methods, and each relation with an arrow: inheritance, realization, composition, aggregation, association or dependency, with multiplicities such as 1 and 0..* and a label. Each class becomes a box with its name, stereotype, fields and methods, with + - # ~ visibility, static members underlined and abstract members in italics. Parents and interfaces are placed above the classes that inherit from or implement them. Lines run in the space between the classes, and a geometry check on the final drawing counts boxes that overlap and lines that cross a class, and checks that each line end carries the marker of its relation kind. The PDF is Letter, A4 or Tabloid; large diagrams go on to more pages with text of at least 7 pt, cut only between classes, with a page list. You also get an SVG, a CSV with one row per class, member and relation, and a JSON copy of the model. A second tool checks the text without drawing.

What it does

Classes, interfaces, abstract classes and enums with fields, methods, parameters and return types
Six relation kinds with UML markers, multiplicities on each end and labels
A line that does not fit the grammar is refused with its line number, nothing is guessed
Geometry check on the drawing: overlapping classes, lines crossing a class, end markers by relation kind
PDF (Letter, A4 or Tabloid) with text of at least 7 pt, SVG, CSV and JSON
A model check: classes that are not declared, duplicate members, inheritance cycles

Try asking

“Class diagram: class Animal { +name: String } class Dog { +bark(): void } Animal <|-- Dog”

“Check my class diagram text for inheritance cycles”

“Draw this domain model as an A4 UML class diagram PDF”

Limitations

Up to 60 classes, 40 members per class, 600 members and 200 relations in all, 100,000 characters
Reads its own text grammar only; it does not read Java, Python or other source code, and it is not full Mermaid or PlantUML
A line that does not fit the grammar is refused with its line number
No packages, notes, generics declared on classes or nested classes
A class whose relation line ends do not fit across one page (about 50 on one edge on Letter) is refused with its name; Tabloid fits more
The PDF font covers Latin, Greek, Cyrillic and Vietnamese; Chinese, Japanese, Korean, Arabic, Hebrew and emoji show as ? in the PDF (the SVG, CSV and JSON keep them)
Files of large diagrams are kept for 1 hour so the download links work, then deleted; download the files to keep them

Add it

ChatGPT: once Zovo Class Diagram is approved, add it from the ChatGPT plugin directory.

Claude: go to Customize > Connectors > Add custom connector and enter https://class-diagram.zovo.one/mcp. No sign-in is needed. Once Zovo Class Diagram is listed in the Claude connector directory, you can add it from there too.

Other MCP clients can connect to the same endpoint: https://class-diagram.zovo.one/mcp