You need administrator rights in Jira to perform the tasks on this page.
Jira provides no easy way to find the IDs of custom fields and their contexts, which are especially useful for scripting and REST APIs. To address this, we added a View Custom Field Contexts page that shows all the Checklist and Checklist Proxy custom fields, including their IDs.
To view custom field and context information:
Go to Administration > Manage apps.
In the sidebar, go to Checklist for Jira > View Custom Field Contexts.
Click on a custom field to expand it and reveal its contexts and their IDs.