Unique key which identifies BigPicture user. It could be obtained from the following endpoint: Teams -> Get teams allocated to boxes https://{base_url}/rest/bigpicture/1.0/public/ppm/teams
In case it cannot be taken from the endpoint above, it could be determined using the following pattern: EXT_USER@<extplatform_id>@<user_id_in_extplatform>.
Replace <extplatform_id> with an ID for an external platform you use data from. If your default external platform is Jira Server, enter 2. Next, replace <user_id_in_extplatform> with a real ID of the user from the external platform you want to use (for Jira Server, enter a user ID in Jira, for another extplatform like Trello, provide a user ID in Trello).
Note: if <user_id_in_extplatform> is an email address, double “@” and use the pattern EXT_USER@@@@email@com, then provide a real email in email@com.