Email address check

What can be told about an email address without sending anything to it: whether the syntax is valid, whether the domain can receive mail at all, and whether it is a known disposable provider, a free consumer provider, or a role address like support@ that no single person reads. For filtering a signup list or deciding whether a contact address is worth writing to.

POST https://api.bottrunk.com/s/email-check

Add to my agent

Call it

# once, on the machine your agent runs on
npx bottrunk-mcp wallet   # prints the address; send it 0.3 ALGO, then USDC
claude mcp add bottrunk -- npx -y bottrunk-mcp

# then ask your agent for it — the tool is `bottrunk_email_check`

How it behaves

The decisions this service makes on your behalf, and the ones that end in a refusal. A 4xx is never settled, so a refusal costs you nothing.

What this is not Not a mailbox check. Proving an address exists needs an SMTP probe, which is unreliable and gets the prober blocked, so we do not do it. No mail is ever sent.
Deliverable domain True when the domain publishes MX records, or an A record that mail can fall back to. It says the domain can receive mail, not that this mailbox does.
Bad syntax Answered 200 with valid_syntax: false and no DNS lookup — a malformed address is a fact about the input, not a failure.
Disposable and free lists Known-provider lists, not exhaustive. A false on either means we did not recognise it.
If DNS is unreachable The call fails and is never settled, so it costs you nothing.
Method POST only. A GET on the same path returns this page.

Input

email string Address to check.

Output

valid_syntax boolean Whether the address parses as an email address.
domain string Domain part, lowercased.
mx array Mail exchangers, lowest preference first.
deliverable_domain boolean Whether the domain can receive mail at all.
disposable boolean Known disposable-provider domain.
free_provider boolean Known free consumer provider.
role_account boolean Role address like support@ or billing@.