Wait API
Bounded waits with after_sequence cursors — no busy polling races for temp mail.
Temporary email API
Wait for the email in your test
Create a disposable inbox, send the mail from your app, and read the code when it arrives. No shared mailbox, and the capture server does not relay mail to the internet.
SMTP capture
AUTH PLAIN on 127.0.0.1:2526 with your API key. Zero Internet relay.
Signed webhooks
HMAC X-Mailby-Signature with durable retries for disposable inbox events.
Quickstart — disposable inbox API
Create an account → Developer console → create mb_live_… key → export as MAILBY_KEY.
1. Create an inbox
curl -sS -X POST https://mailby.app/api/v1/inboxes \
-H "Authorization: Bearer $MAILBY_KEY" \
-H "Content-Type: application/json" \
-d '{"retention_seconds":3600}'2. Inject a test message (HTTP)
curl -sS -X POST https://mailby.app/api/v1/inboxes/$INBOX_ID/messages \
-H "Authorization: Bearer $MAILBY_KEY" \
-H "Content-Type: application/json" \
-d '{"subject":"Verify","text":"Your code is 424242"}'3. Wait for OTP
curl -sS "https://mailby.app/api/v1/inboxes/$INBOX_ID/otp?timeout=60" \ -H "Authorization: Bearer $MAILBY_KEY"
Temporary email API surface
| Method | Path | Purpose |
|---|---|---|
| POST | /api/v1/inboxes | Create disposable inbox |
| GET | /api/v1/inboxes | List inboxes |
| GET | /api/v1/inboxes/{id} | Get inbox |
| DELETE | /api/v1/inboxes/{id} | Delete inbox |
| GET | /api/v1/inboxes/{id}/messages | List messages |
| GET | /api/v1/inboxes/{id}/messages/wait | Wait for next ready message |
| GET | /api/v1/inboxes/{id}/otp | Wait until OTP/code extracted |
| POST | /api/v1/inboxes/{id}/messages | Inject RFC822 or JSON test mail |
| GET | /api/v1/messages/{id} | Message detail + codes/links |
Auth & plans
All /api/v1/* calls require Authorization: Bearer $MAILBY_KEY. Webhooks and SMTP capture are on Premium. A free message can be 5 MB, attachments included. Premium can be 25 MB. Local capture: 127.0.0.1:2526.
Mint a key and run your first wait
Open the developer console, create an API key, and allocate a disposable inbox for your next CI job.
Summary
What is it?
Mailby Test Inbox Cloud is a temporary email API for OTP waits, disposable inbox lifecycle, SMTP capture, and signed webhooks in CI.
How does it work?
Authenticate with an API key, create a disposable inbox, trigger your app, wait for mail or OTP, then delete the temp mail address.
Why use Mailby?
Teams use a dedicated email testing API instead of shared Gmail aliases or public temp-mail dumps.
Key takeaways
- Disposable inbox create/list/delete API
- OTP wait endpoint for CI
- Local SMTP capture — not an open relay
- HMAC-signed webhooks on eligible plans
FAQ
- What is the Mailby temporary email API?
- Test Inbox Cloud lets developers create disposable inboxes, wait for mail, extract OTPs, inject test messages, and receive signed webhooks for CI email testing.
- Does the temp mail API require an account?
- Yes. Create an account, open the Developer console, mint an mb_live_ key, and call /api/v1/* with Bearer auth.
- Is SMTP capture an open relay?
- No. Local SMTP capture binds to 127.0.0.1 with AUTH PLAIN using your API key and only accepts RCPT for inboxes you created.