When you land on api3.cursor.sh, you get a 404 page — there's nothing to see. That doesn't automatically mean it's a scam, but it does mean you can't judge the site by its content. The domain appears to be an API subdomain, likely linked to the Cursor AI editor. For a technical endpoint, this is not unusual: many companies host their APIs on subdomains without public-facing pages.
What we can verify is that the site uses Cloudflare for performance and has a valid SSL certificate, which are positive signs. There are no blacklists or malware warnings. However, there's no way to confirm who owns this specific subdomain or when it was created. The lack of a web archive suggests it's either very new or was never meant to be a standalone site.
If you're asking 'is api3.cursor.sh a scam?', the answer is no — there's no evidence of malicious behavior. But the real question is whether the domain serves its intended purpose. Since it returns a 404, it doesn't appear to be in active use. If you were expecting to reach an API endpoint, this might be a configuration issue rather than a trust problem. For now, treat it as a dead link unless you have independent confirmation from Cursor itself that this subdomain is legitimate.