UiPath Orchestrator provides an out of the box trigger mechanism that allows to start processes at a specific time or when a queue item is added to a queue. This can be limiting in scenarios where you want to chain processes (when process A is done, start process B), or react to unexpected events (process failed, schedule did not start).
O-trigger aims at solving these scenarios by allowing you to create triggers based on Orchestrator events.
O-trigger is designed around the Webhook feature of Orchestrator. Webhooks allow you to configure endpoints where Orchestrator will post data when an event occurs. For example, when a job fails, Orchestrator will push some data regarding the failure (name of the Robot that failed, name of the process that failed, etc.) to all the configured Webhooks.
O-trigger is a web server that can listen for Webhook events and respond with actions. Namely it can send emails and start jobs on Orchestrator when it receives specific events.