Mermaid

Mermaid is an open-source JavaScript-based diagramming description language that has been natively supported by mainstream platforms such as GitHub, GitLab, and Notion.

Mermaid is a text-based diagram description language that allows users to generate flowcharts, sequence diagrams, Gantt charts, class diagrams, state diagrams, and other chart types through concise Markdown-like syntax.

Mermaid's official rendering engine relies on layout libraries such as dagre to automatically arrange node positions, and commonly exhibits issues such as node overlap, chaotic line crossings, and unreasonable spacing when graphs are complex

The workflow in which a language model interprets literature to generate drawing prompts and an image model renders the output is a type of AI agent workflow that chains multiple specialized models through tool calls.

Mermaid is a lightweight diagram description language created by Knut Sveidqvist in 2014, with the core concept of Diagrams as Code.

Mermaid.js describes graphics using a Markdown-like text syntax and has been natively supported by platforms such as GitHub and Notion.

Mermaid's SVG output embeds text as <text> elements and specifies a font that may not exist on the rendering server (e.g. "trebuchet ms", verdana, sans-serif).

Pele is an open-source tool that converts Mermaid diagrams into themeable SVG.

Mermaid supports adding custom CSS classes to nodes via classDef, but the class names are only used at render time, and styles in the output remain primarily inline.

Mermaid supports theme customization through the theme and themeVariables configuration options, ships with built-in themes such as default, dark, forest, and neutral, and also allows overriding variables such as colors and fonts.

The node-link model is a fundamental structure in graph theory and data visualization, where nodes represent entities and links represent relationships, and it is widely used by tools such as D3.js, Cytoscape, and Mermaid.

diagram-design can draw 44 chart types, outputs an HTML file with a single inline SVG, supports redrawing Mermaid, draw.io, and Excalidraw source files, and includes a guided step to extract colors and fonts from the user's website.

The developer fixed the problem by adding a pre-check lint stage that flags unclosed ::: blocks and mismatched subgraph keywords before rendering, and returns the diagram plus a warning list.

In Mermaid syntax, :: is the style class application operator, normally written like `A:::myClass --> B`, and it does not appear on a line by itself.

When rendering an error node, the Mermaid rendering API still returns HTTP 200 OK and a technically completely valid PNG image.

When the Mermaid parser encounters a syntax error that lexically cannot form a complete statement (for example, a line starting with an isolated ::: with no following node name or closing structure), it does not throw an exception, but instead degrades it into rendering an error node.

Mermaid adopts a text-as-diagram paradigm, using a Markdown-like DSL to describe nodes and connections and render standardized graphics; Excalidraw is based on a freehand Canvas drawing surface where element positions are entirely decided by the person.

Codex CLI supports rendering Mermaid flowcharts and LaTeX mathematical formulas directly in the terminal.

Mermaid is a text-based diagramming tool where users describe nodes and edges using Markdown-like syntax, and the tool automatically generates flowcharts, sequence diagrams, class diagrams, and more.

A shared limitation of Mermaid and Graphviz is that their layout algorithms target global optimality, yet users have almost no means of intervening in the layout.