Jenkinsfile-runner: How does artifacts work?

Contributing Jenkinsfile Runner
1

Hello,
I’m wondering how artifacts work when using Jenkinsfile runner.
Where do they go if I use archiveArtifacts? For instance:

archiveArtifacts artifacts: 'deploy/*', fingerprint: true

How to use copyArtifacts?

copyArtifacts projectName: 'MySourceProject'

Thanks