SMS.to API currently supports 2 types of sending sms which are:

• API endpoint delivering 1 single sms (https://developers.sms.to/#9b7afa95-2bcb-4bf7-9cbf-2c1d53599903)
• API endpoint delivering multiple sms to multiple phones or multiple sms to a list (https://developers.sms.to/#a8d1bad4-26aa-48f8-9346-3b2a04485930)

Both API endpoints are following this process:

• Capture the request from the API and pass it to our queueing system
• Process the request asynchonously by validating numbers, correcting and adjusting number prefix where possible, performing analysis on the message and decide what is the best route to deliver the sms
• Deliver the sms based on the route defined after the processing to guarantee the deliverability of the message to the end user's mobile phone.

However, below we will notice that each API endpoint returns a different response. Here is an example of each one:

• API endpoint delivering 1 single sms

  • {
      "message": "Message is queued for sending! Please check report for update",
      "success": true,
      "message_id": "11ec-832f-a6f3fcfe-9fea-02420a0002ab"
    }

    
    

• API endpoint delivering multiple sms to multiple phones or multiple sms to a list

  • {
      "message": "Message is queued for sending! Please check report for update",
      "success": true,
      "campaign_id": "11ec-832f-ecdf64f6-8109-0242ac120004"
    }

      

    If a webhook exist to receive the final status of the message, the payload for that webhook is going to be:

{
  "trackingId": "11ec-832f-a6f3fcfe-9fea-02420a0002ab",
  "messageId": "11ec-832f-a6f3fcfe-9fea-02420a0002ab",
  "phone": "+35799234567",
  "status": "FAILED",
  "parts": 1,
  "price": 0.015
}

   This makes it easy for a developer to match the message_id received on the API response with the messageId or trackingId from the webhook. (Keep in mind that if this approach is selected, we have some limitations on how many requests per second we receive which can be found on https://support.sms.to/support/solutions/articles/43000682464-api-restrictions-rules-responses).

Now in the case of API endpoint delivering multiple sms to multiple phones or multiple sms to a list, as we will see above we receive campaign_id rather message_id. The reason we don't return back message_ids in this API is becauce we are capturing as fast as possible your request and on background we are processing each phone number and message and we try our best that all the messages and phones are valid and can be delivered. This way it reduces any unecessary costs on client's end. However the only thing we cannot guarantee is in case the phone is closed and sms cannot be delivered.

Below you can see the payload from the webhook in the case of getting a campaign_id back:

{
  "trackingId": "11ec-832f-ecdf64f6-8109-0242ac120004",
  "messageId": "11dc-642f-a6f3fcfe-9f4a-02440a0502ab",
  "phone": "+35799123456",
  "status": "DELIVERED",
  "parts": 1,
  "price": 0.015
}