Hi @<1541954607595393024:profile|BattyCrocodile47>

Can you trigger a pre-existing Pipeline via the ClearML REST API?

Yes

'd want to have a Lambda function trigger the Pipeline for a batch without needing to have all the Pipeline code in the lambda function.

Easiest is to use clearml SDK, which basically is clone / enqueue (notice that pipeline is also a kind of a Task). See here: None

next_task = Task.get_task(<pipeline_id_here>)
cloned_task = Task.clone(source_task=next_task)
Task.enqueue(cloned_task.id, queue_name="services")

can ClearML emit an event that I can react to? ...

Easiest to do is if you have logic that triggers it, it would be to wait for the pipeline to finish with wait_for_status , another option is to check the custom triggers: None

If (2) is not possible: is there a way to add an "try/except" component to a Pipeline? ...

Not sure I fully understand what you mean here...