# Plantuml Diagrams

> Create PlantUML source and rendered diagrams for sequence, activity, class, component, deployment, state, and C4-style architecture diagrams. Use when UML semantics are more important than freeform drawing.

- Skill: `yuukias/plantuml-diagrams` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add yuukias/plantuml-diagrams`
- Raw SKILL.md: https://api.skillmd.com/api/skills/yuukias/plantuml-diagrams/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: YuukiAS (https://skillmd.com/u/yuukias)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/yuukias/plantuml-diagrams

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# PlantUML Diagrams

Use PlantUML when a formal UML or C4-style representation is useful.

## Workflow

1. Select the diagram family before writing source.
2. Gather entities, relationships, lifecycle states, actors, or deployment nodes from real artifacts.
3. Write `.puml` as the source of truth.
4. Render locally if PlantUML is available; otherwise use Kroki only if network access is acceptable.
5. Keep generated images next to the `.puml` file and report both paths.

## Diagram Selection

- Sequence: API calls, protocol flow, review/approval workflows.
- Activity: pipelines, decision logic, manuscript or experiment process.
- Class/component: codebase architecture and interfaces.
- Deployment: infrastructure, runtime topology, services.
- C4: context/container/component documentation.

## Boundaries

- Do not force PlantUML for informal ideation; use Mermaid or Excalidraw instead.
- Do not send private architecture to remote Kroki without permission.
- Do not invent classes or services that are not present in source artifacts.