> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mythos.new/llms.txt
> Use this file to discover all available pages before exploring further.

# SEO & social previews

> Set the title, description, icon, and social image for your published Mythos site. These are injected at publish and editable instantly without rebuilding.

When someone shares your site's link or finds it in search, what they see — the title, the one-line
description, the little icon, and the preview image — comes from your site's SEO settings. Mythos lets you
set all of these on the SEO step of the publish wizard, and applies them to your live site without
rebuilding it.

The mental model: your site's files are one thing; the SEO details are layered on top when the site is
served. That's why changing them is instant — there's nothing to rebuild.

<Note>SEO settings are part of [publishing](/publishing/publish). You set them on the SEO step of the
publish wizard (and can edit them later from the published panel). They don't apply to the private preview
— only to the public `*.r21.dev` site.</Note>

## What you can set

| Field        | What it controls                                                        | Limit                           |
| ------------ | ----------------------------------------------------------------------- | ------------------------------- |
| Title        | The page title shown in browser tabs, search results, and link previews | 60 characters                   |
| Description  | The one-line summary under the title in search and link previews        | 160 characters                  |
| Icon         | The small favicon next to the title (browser tab, bookmarks)            | PNG, JPEG, WebP, or ICO         |
| Social image | The large preview image when the link is shared (the og:image)          | An image you upload or generate |

## Why set them

* **Better link previews.** A shared link with a clear title, description, and image gets more clicks than
  a bare URL.
* **Search and discovery.** The title and description are what search engines show.
* **Recognizable in a tab.** A favicon and social image replace the default Mythos icon and preview.

## How to set SEO

<Steps>
  <Step title="Open the SEO step">
    On the publish wizard it's the **Add info to help people find your site** step (step 2). If your site
    is already live, open the Publish panel and choose **Website info** under settings.
  </Step>

  <Step title="Set the icon and title">
    Upload an icon (favicon) and type a title — keep it under 60 characters so it isn't truncated.
  </Step>

  <Step title="Write a description">
    Add a one-line description under 160 characters. Mythos pre-fills a suggested one from your site's
    content — edit it or keep it as is.
  </Step>

  <Step title="Add a social image">
    Upload an image or select **Generate** to capture a screenshot of your site. This is the large preview
    that shows when your link is shared.
  </Step>

  <Step title="Save">
    Continue through the wizard, or select **Done** if your site is already live. The preview card on the
    step shows roughly how your link will appear.
  </Step>
</Steps>

## Editing SEO after publishing — no rebuild

SEO settings are applied to your live site when it's served, not baked into the build. So you can change
your title, description, icon, or social image on an already-live site and the change takes effect almost
immediately — without rebuilding or republishing the site itself.

<Tip>Got the wording wrong on a shared link? Fix the description in the published panel and re-share. The
update is near-instant — no need to run **Update site**.</Tip>

## Auto-filled defaults

You don't have to start from a blank form. Mythos pre-fills sensible defaults so a published site always
has reasonable preview information:

* **Title and description** are suggested from your site's content, in the site's own language.
* **The social image** defaults to a screenshot of your site.

You can accept these as-is or replace any of them.

## Examples

Good SEO copy is specific and human. For a bakery site:

```
Title:       Flour & Stone — artisan sourdough in Portland
Description: Small-batch sourdough, pastries, and morning coffee. Order ahead for weekend pickup.
```

For a freelance portfolio:

```
Title:       Maya Okafor — product designer
Description: Portfolio of UX and product design work across fintech and health apps. Open for projects.
```

## Limitations & good to know

* **Title and description limits.** Titles cap at 60 characters and descriptions at 160 — longer text is
  truncated in search and previews anyway.
* **Icon formats.** The icon accepts raster images (PNG, JPEG, WebP) and ICO. SVG icons aren't accepted.
* **The social image isn't AI-generated.** You upload one or use a screenshot of your site — Mythos
  doesn't generate a brand image for you.
* **SEO applies to the published site only.** The private preview keeps the default Mythos title and icon.

## Troubleshooting

<AccordionGroup>
  <Accordion title="My new title or image still shows the old one when shared">Mythos serves the updated SEO almost immediately, but social platforms and messaging apps (Twitter/X, Telegram, Facebook, Slack) cache link previews on their side. The old preview can linger until their cache expires. Re-share into a fresh chat, or use the platform's own debugger (e.g. Facebook's Sharing Debugger) to force a re-fetch.</Accordion>
</AccordionGroup>

## FAQ

<AccordionGroup>
  <Accordion title="Do I have to fill these in?">No. Mythos pre-fills a title, description, and screenshot so your site has reasonable preview info even if you skip the fields. Customizing them just makes the result sharper.</Accordion>
  <Accordion title="If I change my description, do I need to republish?">No. SEO settings update on the live site near-instantly — there's nothing to rebuild. Just save the change.</Accordion>
  <Accordion title="Why is my title cut off in a link preview?">Search engines and social platforms truncate long titles. Keep the title under about 60 characters (the field enforces this) so it shows in full.</Accordion>
  <Accordion title="Can I use an SVG for the icon?">No. The icon accepts PNG, JPEG, WebP, and ICO. Use one of those formats.</Accordion>
  <Accordion title="What's the social image for?">It's the large preview that appears when your link is shared on social platforms and messaging apps (the og:image). You can upload one or generate a screenshot of your site.</Accordion>
</AccordionGroup>

## Related

* [Publish your site](/publishing/publish) — the full publish flow that the SEO step is part of.
* [Custom domains](/publishing/custom-domains) — using your own address instead of `*.r21.dev`.