LetterAgent
Mail physical letters by just asking your AI assistant.
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Yes, if you do it carefully: never mail cash, write checks in gel ink, add a restrictive endorsement, use a security envelope, and drop it at the post office, not a curbside mailbox. One plain limit: LetterAgent prints letter text only: it cannot produce a negotiable check, which needs special MICR printing, so mail the check itself separately.
| Precaution | Why |
|---|---|
| Never mail cash: always a check or money order | Cash is untraceable and irresistible; a check can be stopped and reissued |
| Write the check in gel ink, not ballpoint | Thieves "wash" checks with chemicals that erase ballpoint ink so the payee and amount can be rewritten; gel ink soaks into the paper fibers and resists washing |
| Add a restrictive endorsement on the back: "For deposit only" plus the account number | Limits what anyone can do with a stolen check: it can only be deposited to that account, not cashed |
| Use a security envelope (patterned interior) | Stops anyone holding the envelope up to light to read the check inside |
| Drop it inside the post office, not in your curbside mailbox | Raised red flags advertise outgoing mail, and "fishing" theft from residential mailboxes is a common way checks get stolen |
| Use tracked mail for large amounts | Gives you a delivery record and a narrower window to notice if it goes missing |
Two more habits worth having: photograph or note the check number, amount, and payee before you seal the envelope, so you can stop payment precisely if it disappears, and watch the payee's account (or ask them to confirm receipt) rather than assuming arrival. A check that never arrives is only a problem if nobody notices.
Not the check itself, and it is worth understanding exactly why, because the limitation is technical, not a policy choice. A negotiable check is not just text on paper: the routing and account numbers along the bottom are printed in magnetic ink (MICR encoding) that bank sorting machines read, on specific paper stock with security features. Producing one requires specialized check-printing equipment. LetterAgent prints letter text on standard letter paper: it cannot produce a valid negotiable instrument.
What LetterAgent can do is the other half of the job: the cover letter. Payment instructions, the invoice being paid, the account reference, the "please confirm receipt" note: all of that is letter text, printed and mailed normally. So the practical workflow is: write the check yourself, write the cover letter through LetterAgent, and put the check in with the letter (or mail the check separately to the payment address). The letter gets the professional treatment; the check keeps its negotiability.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it's printed and mailed.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
Need help? Ask your assistant: it can check a job's status any time. If it ever can't handle something: hello@getletteragent.com