Open Graph checker
Open Graph is how LinkedIn, Slack, Discord and WhatsApp build the preview card. Search tags do not fill this in. If og:image is missing, you get a text row.
What we measure
The six properties this product already extracts: title, description, image, url, type, site_name. Title, description and image are the ones that decide whether the card looks finished.
How to set them
Absolute http(s) URLs only — relative og:image is dropped by most platforms. 1200×630 is the size that does not get cropped into a square.
og:url should be the canonical address, not the campaign link the person pasted.
See the full audit in your workspace