Introduction

When you share a social-media link, the app you paste it into (Discord, Telegram, Slack) sends a crawler to fetch the page and build a preview card. Most social platforms don’t return usable preview tags to those crawlers, so the card comes back broken, empty, or login-walled.

fixem.be sits in front of the link. You prepend https://fixem.be/ to the URL, and the service fetches the real post itself, extracts the metadata, and returns whatever the caller actually needs.

The crawler-vs-browser split

fixem.be branches on the User-Agent of whoever follows the wrapped link:

• Known crawlers (Discordbot, Telegram, Slack, and friends) get a small HTML document containing OpenGraph and Twitter-Card tags — title, description, image, and where possible an inline video. That’s the preview card.
• Everyone else — a real browser — gets a 302 redirect straight to the original URL. A human never lands on fixem.be; they go where the link points.

A well-formed wrapped URL never returns a 5xx. If a post can’t be resolved, the crawler still gets an honest card (a link card, or a thumbnail) rather than an error, and the browser is still redirected.

The metadata behind the card

The card is built from a single piece of structured metadata per post: kind (video, image, gallery, or link), title, description, author, siteName, an optional image, and an optional video. The API exposes exactly that structure as JSON, so anything the embed card can show, an API client can read.

Media that needs a proxy

Some platforms serve video from a CDN that only accepts requests carrying specific headers or cookies — headers a chat client won’t send. For those, fixem.be signs a short-lived proxy URL (/v/…) that streams the media with the right headers attached. The raw CDN URL and the secret headers never leave the server. See Resolving URLs for how this surfaces in the API.