It sounds like you may be referring to what used to be Live Management, which has been deprecated. To trigger a puppet run on an agent from the master, login to your puppet master, and sudo to the peadmin user account. From there, use mco to trigger a puppet run on a specified agent as follows, where puppetcertname is the agent you wish to trigger the run.
peadmin@pemaster01:~$ mco puppet runonce -I puppet_cert_name
* [ ============================================================> ] 1 / 1
Finished processing 1 / 1 hosts in 164.02 ms
There are other options to trigger runs across multiple systems using other filters. Refer to this link.