--- title: Expandable, Icon, Tooltip, Update description: The remaining four components. --- ## `Expandable` The summary line. Renders expanded. Children: rich content. `Expandable` is a single disclosure with no group container. Use `Accordion` inside an `AccordionGroup` when several disclosures belong together; use `Expandable` for a lone one — typically a nested object's fields under a `ParamField`. ## `Icon` Which icon to render. Reed's prop is `icon`, not `name`. Accessible label. Supply one whenever the icon carries meaning rather than decoration. No children. ## `Tooltip` The hover text. Children: inline content — the text the tooltip attaches to. ```mdx Set `createdAt` on every event. ``` Tooltip text is not reachable on touch devices and does not survive being printed or copied. Never put information a reader needs there — only information that saves a reader a lookup. ## `Update` The version or date this entry covers. One-line summary of the change. Children: rich content — the entry body. ```mdx `reed prefetch` now populates a pinned store, and `build` runs with no network. ``` Useful for release notes and version-stamped entries anywhere on a page. Note that it is **not** what drives a changelog page's structure. A page whose frontmatter sets `type: changelog` is laid out from its date-shaped `##` headings — `## 2026-08-05` — and a date-shaped heading naming an invalid calendar date is reported as a diagnostic. `Update` is a presentational element you may use inside such a page, not the mechanism behind it.