What does 'restart' action of a cluster resource agent do?

Issue

I created an LSB-compliant script resource as follows. There is restart action in the resource configuration. What does this action do?

  Resource: test-script (class=lsb type=cluster_script.sh)
   Operations: force-reload interval=0s timeout=15 (test-script-force-reload-interval-0s)
               monitor interval=15 timeout=15 (test-script-monitor-interval-15)
               restart interval=0s timeout=15 (test-script-restart-interval-0s)           <---
               start interval=0s timeout=15 (test-script-start-interval-0s)
               stop interval=0s timeout=15 (test-script-stop-interval-0s)