Run a LIVE web health & security check on a domain or URL and return an A–F grade with concrete fixes. Performs a real TLS handshake to read the SSL/TLS certificate (validity, trusted issuer, hostname match, days-to-expiry, self-signed detection), determines the negotiated TLS protocol version, checks whether plain HTTP redirects to HTTPS, evaluates the standard security response headers (Strict-Transport-Security/HSTS, Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy), and measures basic availability and latency. Use this before launching a site, when auditing a deployment, or to verify a domain you are about to trust. The check is read-only — it never logs in or modifies the target.

Run the live web health & security check on several domains/URLs at once and return one A–F grade per site. Useful to audit a fleet of sites or compare deployments.