---
title: Head fields
description: What a page's or a site's head may be told to say, and where each field
  may be set.
sidebar:
  order: 20
---

What a page's or a site's head may be told to say, and where each field may be set. Served over MCP as `vizitka://docs/meta`, and by `describe_vocabulary` with `topic=meta`.

| Field | Set on | Type | What it says |
| --- | --- | --- | --- |
| `description` | a page or the site | string | One or two sentences about the page, shown under its title in a search result and on a shared link. Set at site level it describes the whole site. |
| `keywords` | a page or the site | string | Comma-separated words. Search engines have long ignored these; they are here because some other tools still read them. |
| `image` | a page | key | The picture a shared link shows, as the key of a file on this site's disk (`list_files`). The site's own social image is used for a page that names none. |
| `canonical` | a page | url | The address this page is a copy of, as a full https URL. Only for a page published somewhere else first — every page canonicalises to its own address without this. |
| `noindex` | a page or the site | boolean | Ask search engines to leave this out of their index. Set at site level it hides the whole site, which is for a site that is not ready to be found. |
| `author` | the site | string | Who made the site — usually the owner's own name. |
| `theme_color` | the site | string | The colour a phone browser paints its chrome with, as a CSS colour ("#101010"). |
| `twitter` | the site | string | The site's X handle, with the @ ("@mirahalden"). It is what an X card credits. |
| `page_fades` | a page or the site | boolean | Fade from one page of the site into the next instead of cutting. Off unless set, and a page's own value overrides the site's. |
| `morph_refreshes` | a page or the site | boolean | Redraw a page that answers with itself, such as a form's thanks, in place and at the same scroll position. Off unless set, and it asks things of the site's own scripts (`vzk/javascript`). |