Beautiful Mermaid

Render Mermaid diagrams as ASCII/Unicode art (for terminal) or SVG (for files).

Quick Start

# Render ASCII diagram to terminal
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs "graph LR; A-->B-->C"

# Output:
# ┌───┐     ┌───┐     ┌───┐
# │ A │────►│ B │────►│ C │
# └───┘     └───┘     └───┘

Usage

node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs [options] [input]

Options

Option	Description
-f, --format TYPE	Output format: ascii (default) or svg
-t, --theme NAME	Theme for SVG output (default: zinc-dark)
--colors JSON	Custom colors as JSON: {"bg":"#hex","fg":"#hex","accent":"#hex","line":"#hex","muted":"#hex"}. Mutually exclusive with --theme.
--transparent	Transparent SVG background (for inlining into themed pages)
-o, --output FILE	Write to file instead of stdout
--ascii	Use pure ASCII instead of Unicode box-drawing
--themes	List available themes
-h, --help	Show help

Input Sources

• Inline: mermaid.mjs "graph TD; A-->B"
• File: mermaid.mjs diagram.mmd
• Stdin: echo "graph LR; A-->B" | mermaid.mjs -

Examples

ASCII Output (Terminal)

# Flowchart with Unicode box-drawing (default)
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs "graph TD; Start-->Process-->End"

# Pure ASCII for maximum compatibility
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs --ascii "graph LR; A-->B"

SVG Output (Files)

# Create SVG with tokyo-night theme
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs -f svg -t tokyo-night "graph TD; A-->B" -o diagram.svg

# Sequence diagram
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs -f svg -t catppuccin-mocha "sequenceDiagram
Alice->>Bob: Hello
Bob-->>Alice: Hi!" -o sequence.svg

Supported Diagram Types

Type	Syntax
Flowchart	graph TD/LR/BT/RL or flowchart TD/LR/BT/RL
State	stateDiagram-v2
Sequence	sequenceDiagram
Class	classDiagram
ER	erDiagram

Available Themes (17)

Dark themes: zinc-dark, tokyo-night, tokyo-night-storm, catppuccin-mocha, nord, dracula, github-dark, solarized-dark, one-dark, blueprint-dark*

Light themes: zinc-light, tokyo-night-light, catppuccin-latte, nord-light, github-light, solarized-light, vellum*

* = local theme extension (defined in CLI wrapper, not upstream package)

List themes: node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs --themes

When to Use

• Architecture diagrams — Visualize system components directly in conversation
• Data flows — Show how data moves through a system
• State machines — Document application states and transitions
• Sequence diagrams — Illustrate API interactions and message flows
• Class diagrams — Document object relationships
• ER diagrams — Database schema visualization
• Documentation — Export SVG for README files and docs

Cross-Skill Integration

Other skills invoke beautiful-mermaid to generate themed diagrams matching their visual identity. Standard pattern:

# Named theme
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs \
  -f svg -t vellum --transparent -o diagram.svg "graph TD; A-->B-->C"

# Custom colors (for project-specific palettes)
node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs \
  -f svg --colors '{"bg":"#1a1b26","fg":"#a9b1d6","accent":"#7aa2f7"}' \
  -o diagram.svg "graph TD; A-->B-->C"

# ASCII for markdown output (planning, design briefs)
printf 'graph TD\n  A --> B --> C' | \
  node ~/.claude/skills/beautiful-mermaid/scripts/mermaid.mjs -

Theme mapping for consuming skills:

Skill	Theme	Notes
vellum-editorial	vellum	Cream/ink/copper; use --transparent for inline SVGs
Dark slide decks	blueprint-dark	Cyan-on-navy for technical presentations
minoan-frontend-design	--colors	Extract hex from project's DESIGN.md tokens
design-md	github-light	Neutral light theme for token documentation
shape	ASCII mode	Append decision flows to .design-context.md