Box for Salesforce :Too many callouts: 101

We create box folders when salesforce records are created using Box for Salesforce Developer Toolkit. Sometimes We have received callout Limit errors.

we set the batch size 50 but sometimes we run into governor limits. 

Should I set batch size less than current? if so, how large batch size should I set ?  I don't know how many times callouts are invoked when create box folder.

I also wonder why randomly the error occurs.

Here's the problem location（I cannot see the code because this is in a managed package)

Class.box.BoxIntegrationService.getRequestWithAccessTokenBO: line 256, column 1