d2Generate diagrams using D2 (Terrastruct) -- a modern, clean diagram scripting language with excellent auto-layout. Use when the diagram-router selects D2, or when the user wants clean architecture diagrams, nested containers, or prefers D2's aesthetic. Requires the d2 CLI binary.
design-systemShared design principles for all diagram formats -- color theory, composition, typography, accessibility, and quality standards. Referenced by format-specific skills (svg, mermaid, excalidraw, d2). Use when generating any visual diagram to ensure professional quality.
diagram-routerAutomatically select the best diagram format (SVG, Mermaid, Excalidraw, D2) and diagram type based on user intent. Use when the user asks to create, draw, visualize, or diagram something and has not specified a format. Routes to the appropriate format-specific skill.
excalidrawGenerate diagrams with a hand-drawn whiteboard aesthetic by writing .excalidraw files directly. Use when the user wants informal sketches, whiteboard-style visuals, or diagrams they can open and edit in Excalidraw. Saves a local .excalidraw file -- viewing/rendering is handled separately.
mermaidGenerate diagrams using Mermaid syntax -- the most LLM-friendly text-based diagram format. Use when the diagram-router selects Mermaid, or when diagrams will live in GitHub/GitLab markdown, documentation, or when quick generation with broad diagram type coverage is needed. Renders natively on major
svgGenerate professional-quality diagrams as raw SVG. Use when the diagram-router selects SVG, or when the user needs pixel-precise control, custom visuals, threat models, comparisons, Venn diagrams, or any diagram type that other formats cannot handle well. SVG is the most expressive format -- unlimit