A perfect page can still look broken when its shared preview has no image, a stale title, or an accidental localhost URL.
<meta property="og:title" content="Article title">
<meta property="og:description" content="Useful summary">
<meta property="og:image" content="https://example.com/og.jpg">
<meta property="og:url" content="https://example.com/article">
Short answer: set title, description, canonical URL, and a crawlable absolute image URL for each shareable page. Keep metadata sourced from the page itself so the preview cannot drift from content.
Social platforms cache previews aggressively. A fixed tag may need their debugger/rescrape tool before the new image appears.
Treat preview metadata as part of the publishing surface, not an afterthought.
Cover photo by Stanislav Kondratiev on Pexels.