I built a link preview API — here's what I learned about Open Graph
I Built a Link Preview API — Here's What I Learned About Open Graph Link previews seem simple until you actually build something that generates them reliably. I spent weeks digging into how platfor...

Source: DEV Community
I Built a Link Preview API — Here's What I Learned About Open Graph Link previews seem simple until you actually build something that generates them reliably. I spent weeks digging into how platforms parse Open Graph metadata, and I kept running into the same category of problems: missing images, wrong fallbacks, cached bad data. Here is what surprised me. What Link Previews Actually Are (And Why They Break) When you paste a URL into Slack or Twitter, the platform fetches that page, reads the <meta> tags in the <head>, and renders a card. The Open Graph protocol, originally developed by Facebook, defines the standard tags most platforms follow: og:title, og:description, og:image, and og:url. The reason previews break so often comes down to a few recurring patterns: The og:image tag is missing entirely The image URL is relative instead of absolute The image dimensions are wrong and the platform rejects it silently The metadata exists but the page blocks crawlers with a bad r