Calls

Start an outbound call

Initiates an outbound phone call via MCube, Twilio, Exotel, Plivo, Vobiz, Tata Smartflo, SIP, or VoiceLink. Requires sufficient credits and available call concurrency; use GET /calls/concurrency to inspect current capacity before starting a call. The provider you pass must appear in the partner’s allowed_telephony_providers list and its credentials must already be configured. For non-MCube providers, pass connection_id when the partner has multiple active connections for the same provider. Provider-only calls remain backward compatible when exactly one active connection exists for that provider. Pass from_number to choose the caller ID for this call: it must be an active phone number owned on the selected connection (it overrides the agent-bound or default number for Twilio, Plivo, Vobiz, Tata Smartflo, VoiceLink, and SIP; MCube and Exotel caller IDs are fixed, so a differing from_number returns 400). When omitted, the caller ID is the agent-bound number where supported, otherwise the connection default. The resolved caller ID is returned as from_number in the response. The call is placed asynchronously. Use call.status.updated webhooks or GET /calls/{id} to track live status, and use session.completed for final transcript, recording, billing, variables, and extraction data.

POST

calls

start

curl --request POST \
  --url https://api.vocobase.com/api/v2/calls/start \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "to_number": "+919876543210",
  "provider": "plivo",
  "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
  "variables": {
    "callee_name": "Sajal",
    "mobile_number": "+919876543210"
  }
}
'

import requests

url = "https://api.vocobase.com/api/v2/calls/start"

payload = {
    "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    "to_number": "+919876543210",
    "provider": "plivo",
    "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
    "variables": {
        "callee_name": "Sajal",
        "mobile_number": "+919876543210"
    }
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    agent_id: 'a1b2c3d4-e5f6-7890-abcd-ef1234567890',
    to_number: '+919876543210',
    provider: 'plivo',
    connection_id: '9b7f1c44-c87f-4f0c-9124-3c802a9c1a20',
    variables: {callee_name: 'Sajal', mobile_number: '+919876543210'}
  })
};

fetch('https://api.vocobase.com/api/v2/calls/start', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.vocobase.com/api/v2/calls/start",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'agent_id' => 'a1b2c3d4-e5f6-7890-abcd-ef1234567890',
    'to_number' => '+919876543210',
    'provider' => 'plivo',
    'connection_id' => '9b7f1c44-c87f-4f0c-9124-3c802a9c1a20',
    'variables' => [
        'callee_name' => 'Sajal',
        'mobile_number' => '+919876543210'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.vocobase.com/api/v2/calls/start"

	payload := strings.NewReader("{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.vocobase.com/api/v2/calls/start")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.vocobase.com/api/v2/calls/start")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "success": true,
  "data": {
    "call_id": "c1234567-abcd-1234-abcd-123456789012",
    "session_id": "s1234567-abcd-1234-abcd-123456789012",
    "status": "pending",
    "provider": "plivo",
    "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
    "from_number": "+918011223344",
    "to_number": "+919876543210",
    "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890"
  }
}

Authorizations

Authorization

string

header

required

API key in format: rg_live_xxxx. Pass as a Bearer token in the Authorization header.

Body

application/json

agent_id

string<uuid>

required

ID of the agent to use for this call.

to_number

string

required

Destination phone number in E.164 format.

Example:

"+919876543210"

provider

enum<string>

default:mcube

Telephony provider. Defaults to mcube if not specified. The provider must be in your partner's allowed_telephony_providers list and its credentials must be configured.

Available options:

mcube,

twilio,

exotel,

plivo,

vobiz,

tata_smartflo,

sip,

voicelink

connection_id

string<uuid>

Telephony connection ID to use for this call. Required when multiple active connections exist for the selected non-MCube provider. This is how you select which configured from_number/DID set should place the call.

from_number

string

Optional per-call caller ID in E.164 format. Must be an ACTIVE phone number owned on the selected connection (connection_id picks the connection; from_number picks the number within it) -- an unknown number returns 400 VALIDATION_ERROR, never a silent substitution. Overrides the agent-bound/default number for Twilio, Plivo, Vobiz, VoiceLink, and SIP. MCube and Exotel use a fixed caller ID, so any differing value returns 400. For VoiceLink, the DID should be call-ready (mapped and routed) or the carrier may reject the call. fromNumber is accepted for backwards compatibility.

Example:

"+919484957224"

variables

object

Pre-call variable values. Keys must match variable names declared on the agent (Agent.variables). Substituted into the agent's prompt and greeting via {{name}} placeholders. Echoed in the session.completed webhook for partner-side audit. Missing variables render as empty strings.

Show child attributes

Example:

{
  "callee_name": "Sajal",
  "mobile_number": "+919876543210"
}

Response

Call initiated successfully.

success

boolean

data

object

Show child attributes

Get current call concurrencyReturns the authenticated partner account's current phone-call capacity. The limit is resolved as: partner override (`maxConcurrentCalls > 0`) caps the account at that value; partner `maxConcurrentCalls = 0` means unlimited (no cap), in which case `limit` and `remaining` are `null` and `limit_source` is `partner_unlimited`. Active calls are counted from `pending`, `ringing`, and `in_progress` phone-call rows.

Start an outbound call

curl --request POST \
  --url https://api.vocobase.com/api/v2/calls/start \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "to_number": "+919876543210",
  "provider": "plivo",
  "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
  "variables": {
    "callee_name": "Sajal",
    "mobile_number": "+919876543210"
  }
}
'

import requests

url = "https://api.vocobase.com/api/v2/calls/start"

payload = {
    "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    "to_number": "+919876543210",
    "provider": "plivo",
    "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
    "variables": {
        "callee_name": "Sajal",
        "mobile_number": "+919876543210"
    }
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    agent_id: 'a1b2c3d4-e5f6-7890-abcd-ef1234567890',
    to_number: '+919876543210',
    provider: 'plivo',
    connection_id: '9b7f1c44-c87f-4f0c-9124-3c802a9c1a20',
    variables: {callee_name: 'Sajal', mobile_number: '+919876543210'}
  })
};

fetch('https://api.vocobase.com/api/v2/calls/start', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.vocobase.com/api/v2/calls/start",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'agent_id' => 'a1b2c3d4-e5f6-7890-abcd-ef1234567890',
    'to_number' => '+919876543210',
    'provider' => 'plivo',
    'connection_id' => '9b7f1c44-c87f-4f0c-9124-3c802a9c1a20',
    'variables' => [
        'callee_name' => 'Sajal',
        'mobile_number' => '+919876543210'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.vocobase.com/api/v2/calls/start"

	payload := strings.NewReader("{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.vocobase.com/api/v2/calls/start")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.vocobase.com/api/v2/calls/start")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"agent_id\": \"a1b2c3d4-e5f6-7890-abcd-ef1234567890\",\n  \"to_number\": \"+919876543210\",\n  \"provider\": \"plivo\",\n  \"connection_id\": \"9b7f1c44-c87f-4f0c-9124-3c802a9c1a20\",\n  \"variables\": {\n    \"callee_name\": \"Sajal\",\n    \"mobile_number\": \"+919876543210\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "success": true,
  "data": {
    "call_id": "c1234567-abcd-1234-abcd-123456789012",
    "session_id": "s1234567-abcd-1234-abcd-123456789012",
    "status": "pending",
    "provider": "plivo",
    "connection_id": "9b7f1c44-c87f-4f0c-9124-3c802a9c1a20",
    "from_number": "+918011223344",
    "to_number": "+919876543210",
    "agent_id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890"
  }
}

Getting Started

Guides

Partner Onboarding

API Reference

Webhooks

Telephony

Start an outbound call

Authorizations

Body

Response