To use the Cost Tracker API, you need to get a common token for one Jira instance. You can disable the action of the token in Token status and Generate a new token.
With the Cost Tracker API, you have access to cost reports and labor expense by issue key.
Available API requests described here https://cost-tracker.saasjet.com/user-api/v1/docs
Open the Addon menu.
Select Manage API Integration in the list items of the menu.
Enable Token status by moving the token status toggle
Copy the token.
Open the needed Cost report.
In the URL this report contains the parameter reportId and after the symbol equal is a reportId.