Create a key to copy examples filled with your team.

Receiving emails

Hosted inboxes or MX on inbound.your-domain.

KYC must be approved before you can create an inbox or its shared-IP cluster. The API returns 403 {error: kyc_required} before that. Create an active shared cluster first. Then issue a hosted address on the PostShiba inbound zone, or bind one to a verified sending domain.

Hosted or domain-bound

Kind Description
Hosted Omit sending_domain_id. Address lands on CAPSULE_INBOUND_ZONE, for example inbabc123@inbound.postshiba.com. mx_status is not_required. No DNS is needed, but the team still needs an active shared cluster.
Domain-bound Set sending_domain_id on a verified domain. Address is {local_part}@inbound.{sending_domain}. Publish MX on that inbound host only. Do not MX the sending domain itself.

Catch-all local_part * requires a sending domain. Plus-addressing maps agent+thread@ to inbox agent@ and sets thread_id to thread.

Mail retention defaults to 168 hours, then PostShiba purges it. Read retention_hours and each message's expires_at because deployments can change the default. Set reply_to on outbound mail to the inbox address if you want replies to land here.

Create fields

Field Description
name Required.
local_part Optional on hosted. Generated as inb plus hex when blank. * needs a sending domain.
sending_domain_id Blank issues a hosted inbox. Must be a verified domain when set.
webhook_url Optional. Leave blank to store and poll.
webhook_format json or sendgrid_parse. Default json.
tenant_id Optional. The sending domain's tenant wins when sending_domain_id is set. Otherwise the team's default tenant.

webhook_secret is returned on create and show, never on index. Delete disables the inbox. The dashboard can change webhook settings. The API has no update action.

About

PostShiba is the transactional email platform that powers Bento behind the scenes. You can build your own products, like Bento, on top of it.

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