AJO + Adobe Campaign Classic Action for SMS: Correct JSON Payload Structure?

Hello,

I am looking for guidance on how to correctly configure the JSON payload for the SMS channel when using the Adobe Campaign Classic action in Adobe Journey Optimizer / Journey Orchestration.

Our setup is the following:

• Adobe Journey triggers an Adobe Campaign Classic action

• Adobe Campaign Message Center then sends the communication

• We have already successfully implemented email deliveries with this method

The payload we currently use for email works correctly:

{
  "channel": "email",
  "eventType": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "eventType"
  },
  "ctx": {
    "firstName": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "firstName"
  }
  },
  "email": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "email"
  }
}

We then tried to adapt the payload for SMS using the following structure:

{
  "channel": "sms",
  "eventType": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "eventType"
  },
  "mobilePhone": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "mobilePhone"
  },
  "wishedChannel": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "wishedChannel"
  },
  "ctx": {
    "firstName": {
    "toBeMapped": true,
    "dataType": "string",
    "label": "firstName"
  }
  }
}

However, this payload returns a 400 error with the message:

Invalid input

Unfortunately, there is no additional detail in the error response.

The SOAP payload we are trying to emulate in the JSON is the standard for message center: 

<rtEvent wishedChannel="x" type="xx" mobilePhone="XXXXXXXXX">

    <ctx>

        <firstName>x</firstName>

    </ctx>

</rtEvent>

Our questions are:

1. What is the correct payload structure for SMS when using the Adobe Campaign Classic action in Journey Orchestration?

2. Is mobilePhone the correct field name, or should another attribute be used?

3. Are there any mandatory fields for SMS that are not required for email?

4. Is there any documentation or example specifically for SMS payloads with ACC actions?

We reviewed this documentation page, but it only provides examples for email and not for SMS:

https://experienceleague.adobe.com/en/docs/journeys/using/action-journeys/acc-action

Any guidance or working example would be appreciated.