How to determine the Bamboo agent used for build-job via rest-api

[Paul Moors]

Here is the situation: assume I have a project AAA, with buildplan PLAN and buildjob JA and JB.

How can I determine using the rest-api the build-agent that is being used to build buildjob JA for build number 10. 

So the build-key = AAA-PLAN-JA-10