Zernio
Zernio
API Reference

Voice & Calling

Calls

List phone callsGETPlace an outbound phone callPOSTGet a phone callGETHang up a live callPOSTBlind-transfer a live callPOSTGet a call recordingGETEstimate call costGET

Browser Softphone

Mint a browser softphone sessionPOSTDial from the browser softphonePOST

Number Setup

Enable phone calling on a numberPOSTDisable phone calling on a numberDELETEAttach a number to a SIP trunkPOSTDetach a number from its SIP trunkDELETE

SIP Trunks

List SIP trunksGETCreate a SIP trunkPOSTGet a SIP trunkGETDelete a SIP trunkDELETERotate a SIP trunk's passwordPOST
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Voice & Calling

Mint a browser softphone session

Step 1 of the two-step browser softphone handshake. Mints a WebRTC session (token + credential) the browser registers with the @telnyx/webrtc SDK. Once registered, call POST /v1/voice/calls/web/dial with the returned credentialId to place the call. The split avoids bridging to a browser that has not finished registering. The token lives ~1 hour (it must outlive the whole call, not only the handshake).

POST
/v1/voice/calls/web

Authorization

bearerAuth
AuthorizationBearer <token>

API key authentication: send your Zernio API key in the Authorization header, prefixed with Bearer.

In: header

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.voice.createVoiceWebSession();console.log(data);
{  "success": true,  "token": "string",  "credentialId": "string",  "expiresAt": "2019-08-24T14:15:22Z",  "sdk": "string"}
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Estimate call cost

Pre-call cost estimate for a PSTN call: the carrier leg plus optional recording and transcription add-ons. Same billing formula as the post-call invoice, so the quote and the final charge can't disagree. The per-minute figure is deliberately conservative (the real cost comes from the settled carrier record after the call), so estimates trend slightly over the actual invoice. Parity endpoint of `GET /v1/whatsapp/calls/estimate`, minus the Meta line (PSTN calls have no separate Meta bill, so `totalCostUSD` equals `billableCostUSD`).

Dial from the browser softphone

Step 2 of the browser softphone handshake: places an outbound call whose answered leg is bridged to the browser registered with the credential from `POST /v1/voice/calls/web`. The call runs through the normal outbound lane, so it is logged as outbound (from = your number, to = target) and recorded per the number's settings.