Check a country's availability + address constraint
Pre-purchase check, so you can warn BEFORE a customer invests in KYC (regulated review is async, 1-3 days). Tells you whether we have deliverable inventory, and what address the customer needs:
addressConstraint: geo→ the registered address MUST be in one of the returnedareas(the only place we have stock). A different-area address passes pre-approval but the number can never be assigned.addressConstraint: country→ any in-country address works.addressConstraint: none→ field-only / instant country, no address. Call this before starting the KYC form for regulated countries.
API key authentication - use your Zernio API key as a Bearer token
In: header
Query Parameters
ISO-2 country code.
Response Body
application/json
application/json
import Zernio from '@zernio/node';const zernio = new Zernio({ apiKey: process.env.ZERNIO_API_KEY });const { data } = await zernio.whatsappphonenumbers.checkWhatsAppNumberAvailability({ query: { country: 'string', },});console.log(data);{
"country": "string",
"numberType": "string",
"available": true,
"addressConstraint": "geo",
"areas": [
"string"
]
}{
"error": "Unauthorized"
}Release phone number DELETE
Release a purchased phone number. This will: 1. Disconnect any linked WhatsApp social account 2. Decrement the Stripe subscription quantity (or cancel if last number) 3. Release the number from Telnyx 4. Mark the number as released
Get number status GET
Live snapshot of a connected number straight from Meta: the phone-number node (display number, display name + approval, quality rating, messaging-limit tier, throughput, official-business badge, connection status, health_status) and its owning WhatsApp Business Account (name, business verification, timezone, health_status). Fetched live because Meta updates quality/tier/name/health over time; the call also refreshes the cached values shown on the connection card.