curl --request POST \
  --url https://api.example.com/api/make_call \
  --header 'Content-Type: application/json' \
  --data '
{
  "agent_id": 123,
  "to_phone_number": "<string>",
  "app_name": "<string>",
  "extra_config": {},
  "additional_context": {}
}
'

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>"
    }
  ]
}