create_mailbox
Business plan: create a sender on your own verified domain, with reply capture wired up automatically.
›Create sarah@mail.acme.com on our verified domain with display name "Sarah at Acme" and start gradual warmup.
What it does
Adds a sending address on a domain that has already verified. When the zone is on the operator Cloudflare account, the inbound routing rule for reply capture is provisioned as part of creation rather than left as a manual follow-up.
Warmup starts by itself once the domain verifies, and `list_mailboxes` shows the day the sender reaches full volume. Senders on domains Raechly runs for you are added by Raechly, not with this tool.
Set `daily_limit` if you want this mailbox to stay below the default ceiling. Setting it higher will not help; the pipeline caps it anyway.
Parameters
| Name | Type | Notes |
|---|---|---|
| domain_id * | string | |
| email * | string | |
| display_name | string | The name people see, e.g. the product name |
| daily_limit | number | |
| purpose | outbound | lifecycle |
* required · Maps to POST /api/mailboxes
What comes back
The mailbox, its warmup state (`pending`) and reply-capture result.
The thing people get wrong
A real person should be reachable at the address. Recipients reply, and a bounce back from your own sending address is a worse signal than the campaign was ever going to be worth.
Use it with
start_warmup
Start the ramp on an older mailbox still pending. New senders start warming on their own.
reconcile_reply_capture
Ensure every active mailbox has a working inbound routing rule — sends are gated on it.
list_mailboxes
List mailboxes with warmup status, daily limits, sent-today counts and reply capture.
More mailboxes tools
See all 147 tools and the connection string on the MCP server page.