API documentation

Authentication

Create a key in Developers → API keys. Send it as Authorization: Bearer ks_…. Keys are displayed once; we store only a hash and cannot show them again.

Send a message

POST /api/public/v1/messages — fields: channel (sms | email), from (approved sender ID or address), to, body, and subject for email.

cURL

curl https://<your-domain>/api/public/v1/messages \
  -H "Authorization: Bearer ks_test_••••••••" \
  -H "Idempotency-Key: order-10482-shipped" \
  -H "Content-Type: application/json" \
  -d '{
    "channel": "sms",
    "from": "MYSHOP",
    "to": "+233244123456",
    "body": "Your order #10482 has shipped."
  }'

Node.js

const res = await fetch("https://<your-domain>/api/public/v1/messages", {
  method: "POST",
  headers: {
    "Authorization": "Bearer " + process.env.KASA_API_KEY,
    "Idempotency-Key": "otp-" + userId,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({ channel: "sms", from: "MYSHOP", to: "+233244123456", body: "Your code is 482910" }),
});

Response · 202 Accepted

{
  "id": "msg_01J9Z3K8",
  "status": "queued",
  "segments": 1,
  "mode": "test"
}

Errors

Errors return { "error": { "code", "message" } }.

Status	Code	Meaning
400	invalid_request	A field is missing or malformed. The message field explains which.
401	invalid_api_key	The key is missing, malformed, revoked or unknown.
402	insufficient_balance	Your wallet can't cover the estimated cost.
409	idempotency_conflict	The Idempotency-Key was reused with a different body.
422	recipient_opted_out	The recipient opted out of this channel.
429	rate_limited	Too many requests. Retry after the Retry-After header.
503	provider_not_configured	No messaging supplier is connected for this channel yet.

Webhooks

Status events: message.accepted, message.delivered, message.failed. Outbound webhook delivery is being finalised and will be configurable in the developer portal.

Support

Signed-in customers can reach the team from their workspace. A public support channel will be listed here once it opens.