Swagger Response

Hii 

When I generate swagger spec for http://api.weatherstack.com/current?access_key=key&query=London , the

spec generated has response section stating , response is a json string.  But in response section (200)of spec ,I was expecting the list of response tags(fields) as response has current weather data in json format.

When I tested a sample deployed in my local system(server), I am getting spec , in which response section (200) has actual response fields.

I want to understand how the local server, different from a remote server.

thank you...