Email Address Check

What it does

Email Address Check looks at ONE email address and says whether it is worth using. It checks four things: the shape of the address, whether the domain publishes mail servers (public DNS only), whether the domain is a throwaway-mail kind that expires within hours, and whether the part before the @ is a shared role such as info@ or sales@. The verdict is deliverable-domain, risky or invalid, with a plain reason for each check. Every answer is dated and signed with our key, so you can keep it as proof of what was checked, and anyone can check the signature at the stamp page. It never contacts a mail server, never asks whether the mailbox exists, never guesses or suggests an address, and keeps no copy of the address. No model, no list mode.

Who it is for

Agents and people who are about to send to, save or sign someone up with an email address, and want a quick, checkable read first: a sign-up form, a contact list entry, an outreach step, an invoice contact.

Price

Free, no sign-up: 200 checks a day per address. Paid calls are not offered.

Limits

One address per call, no lists. It reads public DNS for the domain only. It never connects to a mail server and never tests whether a mailbox exists, so 'deliverable-domain' means the domain can receive mail, not that this inbox is real or that a message will arrive. Our throwaway-domain and role lists are short and incomplete: a domain that is not on them is not proven to be a real inbox. A free provider such as gmail.com is reported as a fact, not as a risk. No-MX domains that fall back to a web address are marked risky. If DNS did not answer, the answer is risky with 'try again', never invalid. The signed record holds a salted hash of the address, not the address; we keep no copy. At most 20 checks of one domain an hour per caller.

For developers: try it

POST https://llpro.ai/mcp
{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"email_address_check","arguments":{"address":"[email protected]"}}}
-> verdict (deliverable-domain / risky / invalid), reasons, four checks (syntax, mail servers, throwaway domain, role address), facts, signed observation, receipt, stamp link

For agents

Tool email_address_check on https://llpro.ai/mcp and in the tools list. Signed answers are checked with the public key below (signer llpro1:pvykld7urt7qqmo4pepmuaajpu): an Ed25519 signature over the observation as canonical JSON (sorted keys, no spaces).

Public key (base64): OUiCmdA1ZDq3uhiHAKBjsjpMIqOHjenCFaDZas8I+NY=

This tool exists to be found by agents that search MCP registries for email validation, address verification and sign-up checks (road: MCP registries, through the Campus gateway: MCP, Agent2Agent and REST). It gives one signed, checkable answer per call; keep the signed observation with your work so a person can see what was checked and when. How a stamp is checked: https://llpro.ai/stamp

Next

• Connect your agent: Use this and the other LLPRO tools from your own agent.
• Get your agent: No agent yet? Get one that asks first.
• Hand the whole job to the Hub: An address is one part. Tell the Hub the job (clean a list, set up outreach, vet a domain); it routes you to the right check.

For agents: this page as Markdown · JSON · llms.txt · MCP endpoint llpro.ai/mcp · agent card