Who this is for: MiniMoth is designed for indie developers, startups, and anyone building for Indian users who needs WhatsApp/SMS OTP without the overhead of a WhatsApp Business Account, DLT registration, or session management.
Delivery: Every OTP is sent over WhatsApp first, falling back to SMS automatically if WhatsApp delivery fails. Both channels run on MiniMoth's own infrastructure — a verified WhatsApp Business Account and a TRAI DLT-registered SMS sender — so you never set up a WABA, register a sender ID, or manage compliance for either one. You get one simple API; MiniMoth handles both channels behind it.
POST /v1/otp/send', description: 'MiniMoth generates a 6-digit code and delivers it via WhatsApp first, falling back to SMS automatically if WhatsApp fails. You are charged ₹0.35 at this point.' },
{ marker: '~', title: 'Optionally check delivery status', description: 'Call GET /v1/otp/status/:otp_id using the otp_id from step 1. Tells you whether the code landed on WhatsApp or SMS. Useful for showing delivery confirmation in your UI before the user enters the code.', tone: 'muted' },
{ marker: '2', title: 'User enters the code in your app', description: 'You collect the 6-digit code from your UI and send it to your server.' },
{ marker: '3', title: 'Your server calls POST /v1/otp/verify', description: 'MiniMoth checks the code and returns an access_token and refresh_token on success.' },
{ marker: '✓', title: 'Phone number verified — user is authenticated', description: 'Use the tokens to validate every subsequent request, or bring your own session system. See Sessions and Recipes.', tone: 'final' },
]} />
## 1. Get an API key
Create a project in the [dashboard](https://app.minimoth.dev/register). Every project gets an API key in the format `mm_live_...`, shown once on creation and available any time under Project Settings.
2. Send and verify an OTP with the Node.js SDK
[@minimoth/sdk-node](https://www.npmjs.com/package/@minimoth/sdk-node) is the fastest way in — it handles phone normalisation, token management, and auto-refresh, so there's no boilerplate around the raw API.
```bash
npm install @minimoth/sdk-node
```
```typescript
import { MiniMoth } from '@minimoth/sdk-node'
const mm = new MiniMoth({
apiKey: process.env.MINIMOTH_API_KEY, // mm_live_...
})
// 1. Send OTP — delivered via WhatsApp first, falls back to SMS automatically
const { otpId } = await mm.otp.send({ phone: '+919876543210' })
// 2. Verify the code — never throws, always returns a result
const result = await mm.otp.verify({ phone: '+919876543210', otp: '123456' })
if (!result.valid) {
// result.code: 'INVALID_OTP' | 'OTP_NOT_FOUND' | 'VERIFY_RATE_LIMITED' | ...
} else {
// Phone is verified — result.accessToken, result.refreshToken, result.sessionId
}
```
**Accepted phone formats:** `+91XXXXXXXXXX` or bare 10 digits `XXXXXXXXXX`. The 10-digit number must start with 6–9.
`accessToken` is valid for 5 minutes. `refreshToken` is valid for your project's configured refresh window (default 10 days, max 30 days). See [the full Node.js SDK guide →](/docs/sdk-nodejs) for auto-refresh, session validation, and framework examples.
## Using another language, or calling the API directly
Not on Node.js, or want to talk to the REST API yourself? Two endpoints, no SDK required:
Send an OTP
```javascript
const res = await fetch('https://api.minimoth.dev/v1/otp/send', {
method: 'POST',
headers: { 'X-Api-Key': 'mm_live_...', 'Content-Type': 'application/json' },
body: JSON.stringify({ phone: '+919876543210' }),
})
const { otp_id } = await res.json()
// otp_id can be used with GET /v1/otp/status/:otp_id to check delivery
```
The response includes an `otp_id` that can be used to poll delivery status.
### Check delivery status (optional)
```javascript
// Optional — poll delivery status before showing "OTP sent" in your UI
const res = await fetch(`https://api.minimoth.dev/v1/otp/status/${otp_id}`, {
headers: { 'X-Api-Key': 'mm_live_...' },
})
const status = await res.json()
// { otp_id, channel: 'whatsapp' | 'sms', status: 'queued' | 'delivered' | 'failed', delivered_at }
```
MiniMoth first tries WhatsApp; if that fails, SMS is sent automatically. The `channel` field tells you which was used. This step is optional — you can call `otp/verify` directly without checking status first.
### Verify the code
```javascript
const res = await fetch('https://api.minimoth.dev/v1/otp/verify', {
method: 'POST',
headers: { 'X-Api-Key': 'mm_live_...', 'Content-Type': 'application/json' },
body: JSON.stringify({ phone: '+919876543210', code: '123456' }),
})
const { access_token, refresh_token, expires_at, identity_id } = await res.json()
// expires_at is the access_token expiry (ISO 8601)
// identity_id is stable across every future login from this same phone number
```
`access_token` is valid for 5 minutes. `refresh_token` is valid for your project's configured refresh window (default 10 days, max 30 days). See [Sessions](/docs/sessions) for how to refresh and validate tokens, and [Identity](/docs/identity) for what `identity_id` is used for.
Just need OTP delivery? You don't have to use MiniMoth's session tokens at all. If you already have your own auth system, call otp/send + otp/verify to confirm the phone number, then create a session in your own system. See the OTP-only recipe.
---
Full documentation index: https://minimoth.dev/llms.txt