Beautiful Mermaid Renderer

Overview

Render Mermaid source into Unicode/ASCII box-drawing diagrams for terminal/chat output, or into SVG for embedding in docs/UIs.

Quick start (Bun)

1. Install dependencies (one-time per machine):

cd ~/.codex/skills/beautiful-mermaid-renderer && bun install

2. Render Unicode (default) to stdout:

cat diagram.mmd | ./scripts/render.sh --format unicode

3. Render ASCII (maximum compatibility):

cat diagram.mmd | ./scripts/render.sh --format ascii

4. Render SVG to a file:

cat diagram.mmd | ./scripts/render.sh --format svg --out diagram.svg

Workflow

1. Draft or collect Mermaid source

• Prefer small diagrams that fit in a chat/terminal viewport.
• When replying, include the Mermaid source in a fenced mermaid block when it helps the user edit or reuse it.

2. Render for user viewing (default)

• Prefer --format unicode and paste the output in a fenced code block.
• If box-drawing characters display poorly, rerender with --format ascii.

3. Render SVG when needed

• Use --format svg and write to a file (--out).
• Optionally apply a built-in theme (--theme) or custom colors (--bg / --fg).

CLI reference (scripts/render.sh)

• --format <unicode|ascii|svg> (default: unicode)
• --in <file> (optional; otherwise read from stdin)
• --out <file> (optional; otherwise write to stdout)
• --theme <name> (SVG only) and --list-themes
• --bg <color> / --fg <color> (SVG only; overrides theme)
• --transparent (SVG only)
• --paddingX <n> / --paddingY <n> / --boxBorderPadding <n> (text only)