kevinslin

dev.mermaid

Generate Mermaid diagrams with proper syntax. Use when creating flowcharts, sequence diagrams, class diagrams, or any other Mermaid visualizations. Ensures correct label quoting to prevent parsing errors.

kevinslin 6 Updated 5mo ago
GitHub

Install

npx skillscat add kevinslin/llm/dev-mermaid

Install via the SkillsCat registry.

SKILL.md

Dev Mermaid

Overview

This skill provides syntax guidelines for generating valid Mermaid diagrams. Mermaid is a diagramming language that renders text into diagrams, but it's strict about parsing—improper syntax causes rendering failures.

Syntax Rules

When generating Mermaid:

  1. Always wrap node labels in double quotes if they contain any of the following:

    • Parentheses ( )
    • Commas ,
    • Arrows like ->, =>,
    • Function-like text (e.g. foo(a, b))
    • Operators or symbols (+, -, _ in method names combined with punctuation)
  2. Use this pattern:

    A["label text here"]

    not:

    A[label text here]
  3. <br/> is allowed inside quoted labels.

  4. Decision nodes {} may remain unquoted only if they contain simple words (e.g. {dryRun?}).

  5. If unsure whether a label is safe, quote it anyway — quoted labels always parse correctly.

  6. Never rely on Mermaid to "guess" intent; Mermaid is a grammar parser, not markdown.

Mental Model (Important)

Mermaid is not Markdown.
It is closer to a programming language.
If something looks like code, Mermaid will try to parse it as code.

Quoting labels opts out of that behavior.