Use the mode query parameter to specify if you want the x-tyk-api-gateway stripped out.
Api key
ID of the API you want to fetch.
By default mode is empty which means it will return the Tyk API OAS spec including the x-tyk-api-gateway part. When mode=public, the Tyk OAS API spec will exclude the x-tyk-api-gateway part in the response.
public Exported API definition file
The response is of type file.