Identifying which Actor called a permission

I have multiple parties that are valid for a permission, I want to sent a notification which contains the name of actor which actually invoked the permission,
notify milestoneApproval(Contract, Milestone, “was approved by “ + getUsername(callingParty)”)

where getusername is a function like in the npl-demo

Hi @Sandy . So currently, this is not possible from within NPL, as parties are defined as claims and unless the claims do not contain the username, this would not be possible. Commands that were used to invoke the permission contain user_id and caller within the agent. However, this information is not available from within NPL, but can be retrieved via commands API GET/api/streams/commands as streams Streams - Noumena Documentation or GET/api/engine/commands/{commandId} Core - Noumena Documentation