In the Recurly v3 API, the limit parameter impacts the number of results that are returned per API request. This is due to a Pager class that will continue to make API requests until the entire record set is exhausted.
For example, let's assume that there are a total of 100 Subscriptions in total. If you specify a limit of 100 then there will be a single ListSubscriptions() API request that returns all 100 records. However, if you specify a limit of 50, then there will be 2 API requests required to consume all of the records.