activity

activity diagram (uml-mcp)

diagram_type: activity
Backend: plantuml
Output formats: png, svg, pdf, txt, base64

Shows workflows or business processes

Load the workflow skill uml-mcp-diagrams for URL-first replies, progressive discovery, and which MCP tool to call. This file is notation only; it does not add an MCP tool.

Notation tips

• Use start/stop, decisions (if/endif), fork/join, and swimlanes when multiple actors.
• Label every branch exit.

Themes

Pass theme to generate_uml / generate_uml_image (PlantUML built-in name). The server injects !theme <name> after @startuml when the source has no !theme yet.

Recommended: cerulean, materia, sketchy, cyborg, plain, aws-orange, blueprint, sandstone.

Match the page background (also see MCP prompt diagram_theme):

• light / white: cerulean, materia, plain, sketchy, sandstone
• dark / black: blueprint, cyborg, black-knight, carbon-gray, crt-green
• B&W / print: plain, sketchy, sketchy-outline, mimeograph, lightgray

Or embed in source:

@startuml
!theme cerulean
' … diagram …
@enduml

Starter template

@startuml
start
:Do something;
if (OK?) then (yes)
  :Continue;
else (no)
  :Handle error;
endif
stop
@enduml

Example

@startuml
start
:Receive order;
:Validate order;
if (Valid?) then (yes)
  :Process payment;
  if (Payment OK?) then (yes)
    :Ship order;
    stop
  else (no)
    :Notify customer;
    stop
  endif
else (no)
  :Reject order;
  stop
endif
@enduml

Render with uml-mcp

1. Set diagram_type to activity exactly.
2. Call validate_uml when the source is untrusted (prefer strict: true for Mermaid sequence).
3. Call generate_uml, generate_uml_image (chat PNG), or generate_uml_batch.
4. Pass theme when this skill's Themes section lists supported values.
5. Surface the returned url / playground (see the workflow skill).