Custom email domains
Use a domain you already own as the From and To address for your agents' email. Setup is three steps and a short DNS wait.
Why bring your own domain?
- Recognizable sender. Recipients see your brand.
- Your own deliverability reputation, separate from a shared sending pool.
- Many agent mailboxes per domain. Run a fleet of agents under one identity.
Apex or subdomain?
You can register either an apex domain (yourdomain.com) or a subdomain (agents.yourdomain.com).
A subdomain is the safer default. It does not touch the apex's existing mail setup, will not displace any inbox you already use for human email, and is easy to undo.
Use the apex only if you are not currently using it for email, or if you are moving the whole domain over to Inkbox.
Before you start
You will need:
- A domain you own, with the ability to edit its DNS records at your registrar.
- An Inkbox API key, or access to the Inkbox Console.
- A few minutes of hands-on time.
Step 1: Register the domain with Inkbox
You can register a domain from the Console or directly through the API.
Console
- Open inkbox.ai/console and go to the Domains section.
- Click Add domain and enter the bare domain (no
https://, no path, no trailing slash). - The Console shows the list of DNS records you need to publish at your registrar. Leave the page open; you will come back to it in Step 2.
API
Domain registration, DNS-record retrieval, verification, DKIM rotation, and deletion are available via the Console and the REST API only. The SDKs and CLI cover list and set-default.
cURLThe response includes the domain object and a dns_records array. Each record has a type, host, and value. Copy them into your DNS provider exactly as returned; treat them as opaque strings.
Apex with existing MX records
If the apex you're registering already has MX records, the request returns 422 with an apex_mx_warning. To displace the existing mail provider, re-send with apex_mx_acknowledged: true. Otherwise, register a subdomain instead.
cURLSPF lookup warning
If the response includes an spf_lookup_report near the RFC 7208 10-lookup limit, flatten or remove unused includes from your existing SPF before mail will authenticate.
Step 2: Add the DNS records at your registrar
These records do two things: they route mail addressed to your domain to Inkbox, and they let recipients verify outbound mail really came from you (so it doesn't get flagged as spam). You're not touching anything else about how your domain works.
Open the DNS settings for your domain at your registrar, and add each record from the previous step exactly as the API returned it.
Provider-specific guides
These are the official "add DNS records" guides for the most common registrars:
| Registrar | Guide |
|---|---|
| Cloudflare | Manage DNS records |
| AWS Route 53 | Creating records by using the Route 53 console |
| Vercel | Managing DNS Records |
| Porkbun | How to Add DNS Records on Porkbun |
| Namecheap | How do I set up host records for a domain? |
| Squarespace Domains | Adding DNS records to your domain |
| GoDaddy | Manage DNS records |
Generic walkthrough
If your registrar isn't listed, the steps are essentially the same everywhere:
- Open the DNS settings page for the domain at your registrar.
- For each record from Inkbox, add a new record with the matching Type, Host (sometimes called Name), and Value (sometimes called Content or Target).
- Leave the TTL at the default.
- Save.
Long DKIM TXT values
DKIM TXT records can exceed 255 characters. Most registrars handle long values automatically, but a few require splitting the value into multiple quoted segments on the same record. If your DKIM record is rejected by the registrar, paste the value into a tool that splits it into 255-char chunks separated by spaces (not newlines), keeping each chunk in its own pair of quotes.
Step 3: Verify
Verification is automatic once the records are in place. To trigger an immediate re-check (instead of waiting for the next polling cycle), click Re-check verification in the Console, or call:
cURLWhat the status values mean
| Status | What it means |
|---|---|
awaiting_ownership | We are waiting to see your ownership TXT record. |
pending | Ownership is confirmed; we are waiting for the rest of the records to propagate. |
verifying | Records are visible; final checks are running. |
verified | Healthy. You can send and receive mail on the domain. |
dns_invalid | One or more records are present but their values don't match what was issued. |
failed | A 72-hour window elapsed without success. Delete the domain and start over. |
degraded | The domain was previously verified, but a record has since been edited or removed. |
pending_deletion | The domain is in its 24-hour delete grace period and can still be restored. |
Most domains reach verified within a few minutes. More than 24 hours almost always means something is wrong with a record value at your registrar; see Troubleshooting.
Using your domain
Once your domain is verified, create mailboxes on it like any other Inkbox domain (Mail API: Mailboxes).
PythonInbound mail flows through the same pipeline as default mailboxes, including webhooks. A dmarc-reports@yourdomain.com mailbox is auto-provisioned to receive DMARC aggregate reports.
Managing your domain
List your domains
PythonPass a status filter (e.g. status="verified") to narrow the result.
Set as default
A verified domain can be set as your organization's default. New mailboxes will use it automatically. To revert, call set-default with inkboxmail.com. Requires an admin-scoped API key; non-admin keys receive 403.
cURLRotate DKIM
You can rotate at any time. Sending isn't interrupted: the old key stays active until the new TXT is published and verified.
cURLDelete
Deletion enters a 24-hour grace period (sending and receiving stop, but the domain can be restored). After 24h it's permanent. If the domain has mailboxes, the API returns blockers; remove them first.
Delete