API docs

Send product email with one endpoint.

NoticeAPI is intentionally transactional-only. Use it for account email, receipts, security notices, invites, and product notifications. Do not use it for cold outreach, bought lists, newsletters, or marketing automation.

POST /api/v1/email/send

Authenticate with `Authorization: Bearer ps_email_...`.

curl -X POST https://noticeapi.com/api/v1/email/send \
  -H "Authorization: Bearer ps_email_..." \
  -H "Content-Type: application/json" \
  -d '{
    "from": "[email protected]",
    "to": "[email protected]",
    "subject": "Welcome aboard",
    "text": "Your account is ready."
  }'

Payload

from	required sender address
to	required email or array
cc / bcc	optional email or array
replyTo	optional email or array
subject	required string
text / html	at least one is required

Error codes

401 invalid key	The API key is missing, malformed, revoked, or wrong.
402 billing_required	Production sending requires a paid active plan.
403 quota_exceeded	The account exceeded its monthly recipient pool.
409 domain_not_ready	The sending domain is not verified.
409 recipient_suppressed	One or more recipients bounced or complained before.
429 rate_limited	The caller exceeded the short-window request limit.

Webhooks

Events are signed with `x-plainsend-signature: sha256=...` using your dashboard secret.

{
  "type": "email.bounced",
  "messageId": "abc123",
  "recipient": "[email protected]",
  "timestamp": "2026-06-23T12:00:00.000Z",
  "detail": "Mailbox unavailable"
}

Launch checklist

1. Create sandbox

Generate a key and send mocked test mail.

2. Add domain

Use a subdomain like send.yourdomain.com and copy DNS.

3. Wire billing

Use the new Stripe account before enabling paid upgrades.

4. Add ACS

Set the ACS connection string after the sender domain is ready.

5. Deploy

Coolify with Docker, Neon DATABASE_URL, and Cloudflare Turnstile.

6. Announce

Lead with transactional email for real product messages, not cold outreach.

Open dashboard