Trojan.Agent refers to a generic Trojan malware detection. It is used for detections that are either associated with no specific malware families or not enough information is available to pinpoint the malware family.
This Trojan contains a Backdoor. It can be controlled from a remote server and has the capability to download more malware on the affected machines. It steals sensitive information off the infected machine and sends it to the remote server.
Malwarebytes can remove this threat without further user interaction. It is recommended to do a full system scan since this backdoor may have been used to install more malware onto the system.