Soapbox communicates with Salesforce via the Salesforce API. Salesforce puts a cap on the number of API calls per 24-hour period.
Viewing API usage in Salesforce
To view API usage for your Salesforce instance to ensure that you are under the daily maximum, go to Setup in Salesforce and click on System Overview. The API Usage module will display shows usage information for API requests in the last 24 hours.
Limits are enforced against the aggregate of all API calls made by the organization in a 24 hour period; limits are not on a per-user basis. When an organization exceeds a limit, all users in the organization may be temporarily blocked from making additional calls. Calls will be blocked until usage for the preceding 24 hours drops below the limit.
Creating automated API usage notifications emails in Salesforce
You also have the option of creating email notifications in Salesforce whereby you can set the percent usage you wish to trigger the email and to whom the email should be sent. For further detail, view About API Usage Notifications.
Increasing API usage Limits
If you need to increase your API usage limit, contact Salesforce for pricing and options.
Reducing the number of Salesforce API calls used by Directories
For tips on reducing the number of Salesforce API calls used by Directories, check out this article.