HTTP/1.1 400 Bad Request
Access-Control-Allow-Credentials: true
Access-Control-Allow-Headers: Content-Type, Authorization, X-Requested-With, X-HTTP-Method-Override
Access-Control-Allow-Methods: GET,PUT,POST,DELETE
Access-Control-Allow-Origin: *
Charset: utf-8
Content-Type: application/json 
Date: Mon, 24 Aug 2015 12:39:17 GMT 
Server: nginx 
X-Powered-By: Express
X-RateLimit-Limit: 30
X-RateLimit-Remaining: 29
X-RateLimit-Reset: 1440419959
X-Response-Time: 16ms
Content-Length: 298 
Connection: keep-alive
Set-Cookie: incap_ses_297_166741=HNKHe0LC6nS3UUoRJSgfBHQQ21UAAAAAv4QKtNyOXIyl6C0jz+/IrA==; path=/; Domain=.pagar.me 
X-Iinfo: 6-22507443-22505778 PNNN RT(1440419956391 49) q(0 0 0 0) r(2 2) U11
X-CDN: Incapsula

{
  "errors": [
    {
      "parameter_name": "interest_rate",
      "type": "invalid_parameter",
      "message": "Taxa de juros está faltando"
    }
  ],
  "url": "/transactions/calculate_installments_amount?api_key=ak_test_R2j5LA1IqqxBZWLfy9yU03dSJbqY6G&max_installments=12&free_installments=3&interest_rate=&amount=120000",
  "method": "get"
}