The Robot service is the brain of all operations. It communicates through an IPC protocol with Studio, Agent Desktop or the Robot Tray, and Robot Command Line Interface to receive and process information, and then to provide the necessary instructions to the Robot Executor.

It is responsible for sending the Robot heartbeat to Orchestrator to communicate execution status or receive new execution orders, acting as a proxy between Orchestrator and the execution hosts.

Windows sessions in which processes are executed are managed and monitored by the Robot service, while also being trusted with the credentials for Robots.

There are two types of Robot service, according to deployment:

• The Service Mode Robot (UiPath.Service.Host.exe):
  • Console application launched by the Service Control Manager (SCM) under the Local System;
  • Best suited for unattended automation scenarios;
  • Has the rights of a machine administrator;
  • Is listed under Windows services;
  • Executes jobs from Orchestrator even if a user is not logged in;
  • Closing the Robot Agent (tray) does not close the service;
  • Deployed by default through UiPathStudio.msi.

• The User Mode Robot (UiPath.Service.UserHost.exe):
  • Windows application automatically launched if the SCM-managed Robot Service is not installed;
  • Best suited for attended automation scenarios;
  • Has the rights of the user that installed it;
  • Is not listed under Windows services;
  • Requires a user to be logged in to execute jobs from Orchestrator;
  • Closing the Robot Agent (tray) also closes the service;
  • Deployed by default through UiPathStudioSetup.exe.