# Mermaid Diagram

> Use this skill whenever creating or editing a Mermaid diagram file. Do not wait for an explicit request — if a diagram is being created or edited, this skill applies.

- Skill: `naykel76/mermaid-diagram` (Agent Skill)
- Install (CLI): `npx skillmds@latest add naykel76/mermaid-diagram`
- Raw SKILL.md: https://api.skillmd.com/api/skills/naykel76/mermaid-diagram/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: naykel76 (https://skillmd.com/u/naykel76)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/naykel76/mermaid-diagram

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## Files

- Store diagrams in `resources/design/` as `.mmd` files.
- Name files in PascalCase matching the diagram subject (e.g. `CourseCompleteSequenceDiagram.mmd`).

## Scope

- Diagram only the process named — do not expand into related flows unless asked.
- If the scope is ambiguous, grill me before proceeding.

## Sequence Diagrams

- Use `actor` for humans, `participant` for system components.
- Use short aliases on `participant` when the display name is long.
- Use `->>` for calls, `-->>` for returns/responses.
- Use `Note over` for phase labels only when there are distinct phases — omit for single-phase diagrams.
- Do not use semicolons (`;`) inside arrow labels — Mermaid treats them as statement terminators.