Data Visualization with OpenChart

Note: SVG design capabilities (logos, icons, graphics) have moved to the opendesign plugin. Install with /plugin install opendesign@opendata-skills.

Source of truth: load the types first

Before authoring or modifying a spec, load the OpenChart type definitions. They are the canonical source for field shapes, enums, and defaults. This skill complements the types — it does not replace them. When this skill and the types disagree, the types win.

Try these locations in order; stop at the first one that resolves:

1. Installed package (most common): node_modules/@opendata-ai/openchart-core/dist/index.d.ts. The full chart, table, graph, sankey, tilemap, and map spec surface is rolled into this single bundled .d.ts.
2. Source repo (if you're working in the openchart monorepo): packages/core/src/types/spec.ts and packages/core/src/types/layout.ts. JSDoc comments here are richer than the bundled .d.ts.
3. Published CDN (no local install, network available): https://unpkg.com/@opendata-ai/openchart-core/dist/index.d.ts (redirects to the latest published version).
4. GitHub raw (if unpkg is unreachable, or you want the richer source JSDoc): https://raw.githubusercontent.com/tryopendata/openchart/main/packages/core/src/types/spec.ts. For version-exact types, pin to a release tag instead of main: https://raw.githubusercontent.com/tryopendata/openchart/core-v<version>/packages/core/src/types/spec.ts, matching <version> to the installed @opendata-ai/* package version. Note main may document unpublished surface.
5. Fallback: if none of the above are reachable (no filesystem, no network fetch), use the type sketches in this skill and flag the uncertainty in your response so the user knows you authored without canonical types.

The names worth grepping for once you have a types file open: ChartSpec, TableSpec, GraphSpec, SankeySpec, TileMapSpec, GeoMapSpec (+ GeoMapGeo, GeoMapPointsLayer), MarkType (the 16-mark union), Encoding, EncodingChannel, MarkDef, Chrome, Metric, EndpointLabelsConfig, Annotation (union), TextAnnotation, RangeAnnotation, RefLineAnnotation, LegendConfig, LabelSpec, SeriesStyle, AnimationSpec, ThemeConfig, A11yConfig, SeriesSearchConfig, YouDrawItConfig.