Superwall Chart Annotations API
Annotations mark what happened on an application's timeline, such as a release, a feature by the App Store or a marketing campaign. Every time-series chart for the application draws them, for everyone with access to it. An annotation with `end_at: null` is a point: one moment, drawn as a line. With an `end_at` it is a range from `start_at` to `end_at`, drawn as a shaded span. Both are exact instants: send ISO 8601 timestamps with a timezone, and they are returned in UTC. A chart places each annotation in the bucket that contains it, so an hourly chart shows a point at its hour. Reading needs the charts:read scope; creating, updating and deleting need charts:write. An application holds up to 1000 annotations. Deletes are permanent; the audit log records every change.