data-visualization
Installation
SKILL.md
Data Visualization & Dashboards
A chart is an answer to a question, not decoration. Before any encoding decision, state the question in one sentence ("Which region grew fastest last quarter?"). The question dictates the chart; the data dictates the scale; perception dictates the encoding. This skill gives the ranking, the chart map, the color math, and the discipline to ship charts that read correctly on any screen.
1. Purpose-first — the question drives everything
Never start from "what data do I have." Start from the verb in the user's question, then map it to an intent. The intent picks the chart (§3). If you can't name the question, you can't pick the chart — and a chart with no question becomes a rainbow blob that demos well and informs nothing.
| The user asks… | Intent | Default chart |
|---|---|---|
| "How do these categories compare?" | Comparison | Bar (horizontal if labels long) |
| "How has this changed over time?" | Trend | Line (area only if cumulative/stacked) |
| "What makes up the total?" | Part-to-whole | Stacked bar / treemap |
| "How is this spread out?" | Distribution | Histogram / box / violin |
| "Do these two move together?" | Correlation | Scatter |
| "Where is this happening?" | Geospatial | Choropleth / symbol map |
| "How does flow move between stages?" | Flow | Sankey / alluvial |
| "Who's on top?" | Ranking | Sorted bar / bump / slope |
| "What's the single number now?" | KPI | Big number + sparkline |