MailPulse is different from most PulseNetwork verticals: it does not return information, it takes an action. Calling POST /api/letters with a settled x402 payment causes a real physical letter to be printed and entered into the mail stream via Lob's Print & Mail network (lob.com), addressed and postmarked per the parameters you submitted. This is irreversible once accepted for printing. Test-mode calls (the default; see below) never print or mail anything and cost nothing.
Every response carries a "mode" field: "test" or "live". In test mode, Lob's test API is called for real (so responses reflect actual API behavior) but no physical mail is ever produced. Live mode — real postage, real ink, real delivery — requires The Aslan Group LLC to have explicitly enabled it server-side; it is not something a caller can trigger by request parameters alone. If you did not receive "mode": "live" in a response, no physical mail was sent.
The from address you submit to POST /api/letters is the sender of record on the physical letter. The Aslan Group LLC and MailPulse are a paid conduit only — we are never the sender, we do not review or endorse the content of any letter, and we bear no responsibility for its content. You (the caller, or the end user/agent on whose behalf you are calling) are solely responsible for:
Every order is capped at a fixed maximum total (advertised as MAX_ORDER_USD, $25.00 by default) enforced server-side before any payment is requested. This is a safety rail, not a service tier — it cannot be raised by request parameters.
Quotes are free and non-binding until paid. Once POST /api/letters payment settles and Lob accepts the letter for print/mail processing, the order is final and non-refundable — this mirrors Lob's own policy and the physical reality that ink and postage, once applied, cannot be recalled. The only exception: if a paid call fails due to our error (a 5xx response after payment settled, or a documented bug on our side), we refund it in good faith on notice to the address below, per the loud-failure and refund practice described in /llms.txt.
POST /api/verify-address reports Lob's deliverability assessment at the time of the call. A "deliverable" verdict is not a guarantee of delivery (recipients move, mail gets lost, USPS data lags reality); a "not verified" or partial verdict is not proof an address is invalid. Use it to reduce — not eliminate — the risk of paying to mail an undeliverable address.
POST /api/letters requires a client_request_id. Resubmitting the identical order under the same client_request_id returns the original result and does not create a second letter or charge a second payment; reusing a client_request_id for a materially different order is rejected. Generate a fresh client_request_id per distinct letter.
Subject to these terms, you receive a non-exclusive, non-transferable, revocable licence to use the responses you pay for within your own applications and workflows. You may not resell, redistribute, or republish MailPulse's API responses as a standalone data product.
Physical mail printing, postage, and USPS induction are performed by Lob (lob.com), a licensed commercial mail provider. Lob is not affiliated with, and does not endorse, The Aslan Group LLC or MailPulse. Where a response carries an attribution field, it must be preserved if you display the data.
To the maximum extent permitted by law, The Aslan Group LLC is not liable for any indirect, incidental, consequential or special damages, non-delivery, delayed delivery, or any decision made in reliance on a response. Total aggregate liability for any claim will not exceed the amount you paid for the specific call giving rise to the claim.
These terms may be updated; the version in force is the one published here at the time of your call. Legal, abuse, and refund notices only: info@theaslangroupllc.com. Governing law: the state of formation of The Aslan Group LLC. There is no help desk; service is self-serve and as-is.
terms in every paid response.