Send instant email
Highest priority queue. Designed for 2FA codes, OTPs, and password resets where sub-5-second delivery is critical.
Processing time: 0–5 seconds. Retries: 5. Do not use for bulk marketing sends.
Authorization
bearerAuth Bearer token authentication. Use a Regular API key for email sending, or an Admin API key for marketing and automation endpoints.
Get your API keys from Settings → API Keys (regular) or Settings → Admin API Keys (admin) in the dashboard.
In: header
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
Response Body
application/json
application/json
application/json
application/json
curl -X POST "https://api.keplars.com/api/v1/send-email/instant" \ -H "Content-Type: application/json" \ -d '{ "to": [ "[email protected]" ] }'{
"id": "msg_1748000000000_a1b2c3",
"object": "email",
"status": "queued",
"from": "[email protected]",
"to": [
"[email protected]"
],
"subject": "string",
"created_at": "2019-08-24T14:15:22Z",
"metadata": {
"priority": "instant",
"estimated_delivery": "0-5 seconds",
"recipients_count": 0
}
}{
"success": false,
"error": "VALIDATION_ERROR",
"message": "Field 'to' is required"
}{
"success": false,
"error": "VALIDATION_ERROR",
"message": "Field 'to' is required"
}{
"success": false,
"error": "VALIDATION_ERROR",
"message": "Field 'to' is required"
}Send high priority email POST
High priority queue. Use for **transactional alerts, notifications, and order confirmations** that should arrive within 30 seconds. Processing time: 0–30 seconds. Retries: 3.
Add contact to audience POST
Add a contact to an audience. If a contact with the same email already exists in the workspace it is reused; otherwise a new contact is created. Requires `contacts:write` scope.