A Python visualization library that handles everything from quick scatter plots to complex 3D scientific charts. The dual API approach is smart: use Plotly Express for fast DataFrame visualizations in a few lines, then drop down to graph objects when you need precise control over annotations or specialized chart types. Covers 40+ chart types including the usual suspects (scatter, bar, heatmap) plus financial candlesticks, geographic maps, and interactive 3D surfaces. Outputs to interactive HTML or static images. The real win is that Express figures are actually graph objects under the hood, so you can start simple and customize later without rewriting. Good choice if you need publication quality charts with interactivity baked in.
npx skills add https://github.com/davila7/claude-code-templates --skill plotly