Mailer
Addresses are validated locally — no lookup service — then a full MIME message is composed. Delivery is switched off on this host, so what you get back is the exact message that would have gone out.
Addresses worth trying
| Address | Verdict |
|---|---|
"odd name"@example.com | valid — quoted local part |
user@[192.168.0.1] | valid — address literal |
a..b@example.com | rejected — consecutive dots |
.lead@example.com | rejected — leading dot |
user@-bad.com | rejected — label starts with a hyphen |
user@example.c | rejected — TLD too short |
a@b.com\nBcc: x@y.com | rejected — header injection |
The subject and name fields are sanitised too: CR/LF and control characters are stripped before they can reach a header. Put a newline in the subject and look for it in the output — it will not be there.