EngageLab OTP API Skill

This skill enables interaction with the EngageLab OTP REST API. The OTP service handles one-time password generation, multi-channel delivery (SMS, WhatsApp, Email, Voice), verification, and fraud monitoring.

It covers six areas:

1. OTP Send — Platform-generated OTP code delivery
2. Custom OTP Send — User-generated OTP code delivery
3. OTP Verify — Validate OTP codes
4. Custom Messages Send — Send custom template messages (notifications, marketing)
5. Template Management — Create, list, get, and delete OTP templates
6. Callback & SMPP — Webhook configuration and SMPP protocol integration

Resources

scripts/

• otp_client.py — Python client class (EngageLabOTP) wrapping all API endpoints: send_otp(), send_custom_otp(), verify(), send_custom_message(), and template CRUD. Handles authentication, request construction, and typed error handling. Use this as a ready-to-run helper or import it into the user's project.
• verify_callback.py — HMAC-SHA256 signature verifier for incoming OTP callback webhooks. Parses the X-CALLBACK-ID header and validates authenticity. Drop into any web framework (Flask, FastAPI, Django) to secure callback endpoints.

references/

• error-codes.md — Complete error code tables for all OTP APIs
• template-api.md — Full template CRUD specs with all channel configurations
• callback-config.md — Webhook setup, security, and all event types
• smpp-guide.md — SMPP protocol connection, messaging, and delivery reports

Authentication

All EngageLab OTP API calls use HTTP Basic Authentication.

• Base URL: https://otp.api.engagelab.cc
• Header: Authorization: Basic \x3Cbase64(dev_key:dev_secret)>
• Content-Type: application/json

The user must provide their dev_key and dev_secret. Encode them as base64("dev_key:dev_secret") and set the Authorization header.

Example (using curl):

curl -X POST https://otp.api.engagelab.cc/v1/messages \
  -H "Content-Type: application/json" \
  -H "Authorization: Basic $(echo -n 'YOUR_DEV_KEY:YOUR_DEV_SECRET' | base64)" \
  -d '{ ... }'

If the user hasn't provided credentials, ask them for their dev_key and dev_secret before generating API calls.

Quick Reference — All Endpoints

OTP Send (Platform-Generated Code)

Use this when you want EngageLab to generate the verification code and deliver it according to the template's channel strategy (SMS, WhatsApp, Email, Voice).

Endpoint: POST /v1/messages

Request Body

{
  "to": "+6591234567",
  "template": {
    "id": "test-template-1",
    "language": "default",
    "params": {
      "key1": "value1"
    }
  }
}

Parameters

Notes on params

• Preset variables like {{brand_name}}, {{ttl}}, {{pwa_url}} are auto-filled from template settings — no need to pass them.
• For custom variables in the template (e.g., Hi {{name}}, your code is {{code}}), pass values via params: {"name": "Bob"}.
• If the template's from_id field is preset and you pass {"from_id": "12345"}, the preset value is overridden.

Response

Success:

{
  "message_id": "1725407449772531712",
  "send_channel": "sms"
}

The send_channel indicates the initial channel — if fallback is configured (e.g., WhatsApp → SMS), the final delivery channel may differ.

For error codes, read references/error-codes.md.

Custom OTP Send (User-Generated Code)

Use this when you want to generate the verification code yourself and have EngageLab deliver it. This API does not generate codes and does not require calling the Verify API afterward.

Endpoint: POST /v1/codes

Request Body

{
  "to": "+6591234567",
  "code": "398210",
  "template": {
    "id": "test-template-1",
    "language": "default",
    "params": {
      "key1": "value1"
    }
  }
}

Parameters

Response

Same format as OTP Send — returns message_id and send_channel.

OTP Verify

Validate a verification code that was sent via the OTP Send API (/v1/messages). Only applicable to platform-generated codes — not needed for Custom OTP Send.

Endpoint: POST /v1/verifications

Request Body

{
  "message_id": "1725407449772531712",
  "verify_code": "667090"
}

Parameters

Response

Success:

{
  "message_id": "1725407449772531712",
  "verify_code": "667090",
  "verified": true
}

Important: Successfully verified codes cannot be verified again — subsequent attempts will fail. Expired codes return error 3003.

Custom Messages Send

Send custom template content (verification codes, notifications, or marketing messages) using templates created on the OTP platform.

Endpoint: POST /v1/custom-messages

Request Body

{
  "to": "+6591234567",
  "template": {
    "id": "test-template-1",
    "params": {
      "code": "123456",
      "var1": "value1"
    }
  }
}

Parameters

Notes on params

• Preset variables ({{brand_name}}, {{ttl}}, {{pwa_url}}) are auto-replaced from template settings.
• For verification code templates, you must pass {{code}} or an error will occur.
• Custom variables need values via params, e.g., {"name": "Bob"} for Hi {{name}}.

Response

Same format as OTP Send — returns message_id and send_channel.

Use Case Examples

Verification code:

{
  "to": "+6591234567",
  "template": { "id": "code-template", "params": { "code": "123456" } }
}

Notification:

{
  "to": ["+6591234567"],
  "template": { "id": "notification-template", "params": { "order": "123456" } }
}

Marketing:

{
  "to": ["+6591234567"],
  "template": { "id": "marketing-template", "params": { "name": "EngageLab", "promotion": "30%" } }
}

Template Management

OTP templates define the message content, channel strategy, and verification code settings. Templates support multi-channel delivery with fallback (e.g., WhatsApp → SMS).

For full request/response details including all channel configurations (WhatsApp, SMS, Voice, Email, PWA), read references/template-api.md.

Quick Summary

Create — POST /v1/template-configs

{
  "template_id": "my-template",
  "description": "Login verification",
  "send_channel_strategy": "whatsapp|sms",
  "brand_name": "MyApp",
  "verify_code_config": {
    "verify_code_type": 1,
    "verify_code_len": 6,
    "verify_code_ttl": 5
  },
  "sms_config": {
    "template_type": 1,
    "template_default_config": {
      "contain_security": false,
      "contain_expire": false
    }
  }
}

List all — GET /v1/template-configs (returns array of templates without detailed content)

Get details — GET /v1/template-configs/:templateId (returns full template with channel configs)

Delete — DELETE /v1/template-configs/:templateId

Template Status

Channel Strategy

Use | to define fallback chains. Examples:

• "sms" — SMS only
• "whatsapp|sms" — Try WhatsApp first, fall back to SMS
• "whatsapp|sms|email" — WhatsApp → SMS → Email

Supported channels: whatsapp, sms, voice, email

Verification Code Config

Callback Configuration

Configure webhook URLs to receive real-time delivery status, notification events, message responses, and system events.

For the full callback data structures, security mechanisms, and event types, read references/callback-config.md.

SMPP Integration

For TCP-based SMPP protocol integration (used in carrier-level SMS delivery), read references/smpp-guide.md.

Generating Code

When the user asks to send OTPs or manage templates, generate working code. Default to curl unless the user specifies a language. Supported patterns:

• curl — Shell commands with proper auth header
• Python — Using requests library
• Node.js — Using fetch or axios
• Java — Using HttpClient
• Go — Using net/http

Always include the authentication header and proper error handling. Use placeholder values like YOUR_DEV_KEY and YOUR_DEV_SECRET if the user hasn't provided credentials.

Python Example — Send OTP and Verify

import requests
import base64

DEV_KEY = "YOUR_DEV_KEY"
DEV_SECRET = "YOUR_DEV_SECRET"
BASE_URL = "https://otp.api.engagelab.cc"

auth_string = base64.b64encode(f"{DEV_KEY}:{DEV_SECRET}".encode()).decode()
headers = {
    "Content-Type": "application/json",
    "Authorization": f"Basic {auth_string}"
}

# Step 1: Send OTP
send_resp = requests.post(f"{BASE_URL}/v1/messages", headers=headers, json={
    "to": "+6591234567",
    "template": {"id": "my-template", "language": "default"}
})
result = send_resp.json()
message_id = result["message_id"]

# Step 2: Verify OTP (after user enters the code)
verify_resp = requests.post(f"{BASE_URL}/v1/verifications", headers=headers, json={
    "message_id": message_id,
    "verify_code": "123456"
})
verification = verify_resp.json()
print(f"Verified: {verification['verified']}")