register_destination

com.402cron/402cron · Verify this server

Claim an https:// URL you control. We answer with a challenge and a SIGNING SECRET that is shown ONCE and never again — store it before you do anything else; it is what lets you verify that a delivery really came from us. The permission covers that path and everything beneath it, nothing above. Verification is one request from us to the exact URL you registered: POST, headers X-402cron-Challenge: <value> and X-402cron-Event: verify, JSON body {"challenge":"<value>"}. Reply within 5 seconds, without a redirect, with a body that is the bare value or {"challenge":"<value>"}; we read the first 512 bytes and do not check the HTTP status (2xx is fine). Then call POST /api/destinations/{id}/verify within 15 minutes of registering. A fixed-response webhook cannot pass: you need an endpoint you can program. Registering a URL that is still pending issues a new challenge and a new signing secret every time — the old secret immediately stops verifying deliveries; a verified URL is left untouched unless you add ?rotate=1. The daily verification allowance (10 per destination, 40 per client, UTC day) does not reset on re-registration.