Starting a call

To start a call from external system, execute the following javascript to open a Yack popup window

Start Call

The following URL encoded parameters are appended to the URL:

phone-number string required

Either in home country for organisation or with country code

call-link string optional

If set, code prefixed by a reverse domain name which will allow the calling system to link to the yack call

callback-url string optional

If set, Yack will call a webhook on this URL when the transcription is available.

The calling system may choose to create unique URLs for each call by embedded parameters in the callback URL

callback-token string optional

Token that will be included in webhook call - calling system may choose to ignore this parameter if identifiers are added to callback URL

team-id number optional

If sent, Yack will attach the call to the specified team. If not set, Yack will use the first team available to the Yack user which has outbound calling enabled.

user-email string optional

If sent, Yack will check that the current user has email specified, otherwise will use any user account currently logged into yack

transcript-required ‘true’ or ‘false’ optional

if ‘true’, Yack will send full transcript. Otherwise, only call meta data will be sent

transcript-update-notification ‘true’ or ‘false’ optional

if ‘true’, Yack will resend transcript when it is edited within Yack 

Starting a call examples

Create a simple html link on your side with 

<a href=””  target="_blank">start call</>

Or use script:‘’);

Call Link URL

If a call-link parameter was specified by the integrating system when the call was created, the calling system may link to the Yack call transcript using the following URLs

Full Yack UI[call-link specified when call was created]

Yack Overlay UI  - Yack single room UI without navigation - suitable for use in iframe[call-link specified when call was created]?overlay=true

If duplicate calls were started with the same call-link specified, Yack will open the most recent call.

Callback Webhook

The calling system will need to implement the following webhook and deploy on the callback URL specified when the call was created

  • Url: defined in ‘callback-url’ parameter
  • Method: POST
  • Json in following format

The body of the message will contain a json object with structure

export interface ITranscriptionReadyWebhookBody {

  fullUrl: string;

  overlayUrl: string;

  callRoomId: number;

  callUuid: string;

  callDuration: number;

  callStarted: number; (epoch)

  callFinished: number; (epoch)

  transcriptionMessages: ITranscriptionMessage[];


export interface ITranscriptionMessage {

  offset: number; (miliseconds from start of call)

  userName: string;

  text: string;

  date: number; (epoch)

  id: number; (message id)

  fullUrl: string;

  overlayUrl: string;


Callback Webhook sample project

The webhook is implemented as a project in Glitch which allows you to run the project and view and modify the code.

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