When you receive an incoming call, you can set up your Call Flow such that you can send a dynamic reply to the caller.

To do this, use the "SMS Applet" in your incoming Call app (aka the Callflow). You are able to trigger two types of SMS from the SMS Applet - Static and Dynamic SMS.

To have this implemented, please use the SMS applet in the section "After the call conversation ends..." for the calls that have been completed and in "If nobody answers..." in case the call is missed.

Static SMS-

Static SMSes is an SMS type, which has the same content every time the SMS is triggered.

eg: "Thank you for calling XYZ Support. We hope all your queries have been addressed. For further assistance from our end, do write to"

If you want to send a static SMS, you can select the DLT approved Template Choose a SMS Template and add the same to the text box. The prerequisite is to have an approved header/sender ID as well and the same must be added against the ExoPhone number assigned in the incoming call flow. How to assign sender ID, please find here: Header (Sender ID) Registration

Dynamic SMS-

Dynamic SMS are the SMSes in which the content is changed Depending on different parameters. These parameters include the From Number, the To number and other Parameters which would be relevant to the call you had. The dynamic SMSes can only be triggered using API end point.

Note: In case you are using a prebuilt app like the MissCall app or the Oak tree App, you can just enter your URL in the SMS textbox provided

Before the GET request, Exotel will make an HTTP HEAD request to make sure that the URL is indeed returning the correct 'ContentType' as mandated below. 

The GET request that Exotel makes to the URL will have the following query parameters:

CallSidstring, unique identifier of the call
Fromstring, the number of the caller
Tostring, your Exotel company number to which the call came
digitsstring, If there was a Gather or a Menu applet before this SMS applet, this is the DTMF input that was gathered 

If you want to send an SMS reply to the caller, the HTTP response MUST
- the HTTP response must have 'ContentType' header set to 'text/plain'. 

- the HTTP body must have the reply to send

For example, if you've configured
we will make an HTTP GET request to

Sample php script which sends dynamic reply

header('Content-type: text/plain');
$dynamicReply = "Hello";
// Insert your logic here to use $_REQUEST to construct the dynamic response
echo $dynamicReply;

Now you can add multiple SMS-templates, it will send one SMS randomly. It will be helpful in marketing/advertising your features/offers/services. You can add multiple Templates to the SMS Applet, by clicking on the "+" sign as shown in the annotated screenshot.

In case you have any queries regarding the same, you can always reach out to our Support Team, and we are happy to assist you!

Support Contact details:


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