| name | uml |
| description | Create UML diagrams using PlantUML syntax. Best for software modeling — Class, Sequence, Activity, State Machine, Component, Use Case, and Deployment diagrams with concise text-based notation and auto-layout. |
| metadata | {"author":"UML diagrams are powered by Markdown Viewer — the best multi-platform Markdown extension (Chrome/Edge/Firefox/VS Code) with diagrams, formulas, and one-click Word export. Learn more at https://docu.md"} |
UML Diagram Generator
Quick Start: Choose diagram type → Write PlantUML text → Define elements and relationships → Wrap in ```plantuml fence.
⚠️ IMPORTANT: Always use ```plantuml or ```puml code fence. NEVER use ```text — it will NOT render as a diagram.
Critical Rules
- Every diagram starts with
@startuml and ends with @enduml
- Use standard PlantUML keywords:
class, interface, abstract, enum, actor, participant, component, node, database, package
- Relationships use arrow syntax:
-->, <|--, *--, o--, ..>, ..|>
- Use
skinparam for global styling and colors
- Use
#color on individual elements for specific colors
- Notes use
note left of, note right of, note over, or standalone note "text" as N
UML Diagram Types
| Type | Purpose | Key Syntax | Example |
|---|
| Class | Class structure and relationships | class, interface, <|-- | class-diagram.md |
| Sequence | Message interactions over time | participant, ->, --> | sequence-diagram.md |
| Activity | Workflow and process flow | start, :action;, if/else | activity-diagram.md |
| Swimlane Activity | Multi-role activity with swimlanes | |Lane|, :action; | swimlane-activity-diagram.md |
| State Machine | Object lifecycle states | state, [*] --> | state-machine-diagram.md |
| Component | System component organization | component, [name], interface | component-diagram.md |
| Use Case | User-system interactions | actor, usecase, (name) | use-case-diagram.md |
| Deployment | Physical deployment architecture | node, artifact, database | deployment-diagram.md |
| Object | Runtime object snapshot | object "name" as id | object-diagram.md |
| Package | Module organization | package "name" | package-diagram.md |
|
Mxgraph Stencil Icons
draw-uml supports 9500+ mxgraph stencil icons (AWS, Azure, Cisco, Kubernetes, etc.) via the mxgraph.* syntax. Default colors are applied automatically — you do NOT need to specify fillColor or strokeColor.
Full stencil reference: See stencils/README.md.
Syntax
mxgraph.<namespace>.<icon> "Label" as <alias>
mxgraph.<namespace>.<icon> "Label" as <alias> #color
mxgraph.<namespace>.<icon> <alias>
mxgraph.<namespace>.<icon> — the stencil shape key (e.g. mxgraph.aws4.lambda, mxgraph.kubernetes.pod)"Label" — display text (quoted if contains spaces, unquoted for single word)as <alias> — identifier for use in relationships#color — optional override color (e.g. #FF6600, #LightBlue)
Examples
@startuml
' Simple icon declaration
mxgraph.aws4.lambda "Lambda\nFunction" as fn
mxgraph.aws4.api_gateway "API GW" as gw
mxgraph.aws4.dynamodb "DynamoDB" as db
gw --> fn
fn --> db
@enduml
@startuml
' Kubernetes architecture with icons
mxgraph.kubernetes.ing "Ingress" as ing
mxgraph.kubernetes.svc "Service" as svc
mxgraph.kubernetes.pod "Pod" as pod
mxgraph.kubernetes.deploy "Deployment" as deploy
ing --> svc
svc --> pod
deploy --> pod
@enduml
@startuml
' Mixing standard UML with stencil icons
node "Cloud" {
mxgraph.aws4.ec2 "EC2" as ec2
mxgraph.aws4.rds "RDS" as rds
}
database "Legacy DB" as legacy
ec2 --> rds
rds --> legacy
@enduml
