We are the Formidable API addon to retrieve response  from an API for various SEO calculation End Points.
The only way I have been able to get a successful response from the API is by presently hardcoding the payload as RAW data

[
{
"target": "digital.com.au",
"location_code":2036, 
"language_code":"en", 
"ignore_synonyms":false, 
"limit":100
}
]

If I replace

"target": "digital.com.au",

with 

"target": [86],

or 

"target": "[86]",

then the response fails. How can I prevent this from happening so that I can use dynamic data?