Observability
How well you can tell what your app is doing while it runs, and why something went wrong, from the information it records.
The degree to which a system's internal state can be understood from its outputs, typically logs (records of events), metrics (numbers over time, like error rate), and traces (the path one request took through the system). Good observability lets you answer new questions without shipping new code.
A car with a dashboard showing speed, fuel, and warning lights, versus one with no dashboard at all. Both drive, but only one warns you before the engine dies.
Agents debug by reading evidence. If your app records little, your agent is guessing about what happened in production. Better observability means the next bug takes minutes to diagnose, not days.
I can't see why the job fails in production. Observability is thin here. I'd add structured logs with the order ID and an alert on the error rate, then we'll know which step fails.
Improve observability for the checkout flow: log each step with the order ID, record errors with enough context to debug, and never log card numbers or passwords.
Thinking observability just means adding more logs. Noisy logs without context don't help. The goal is answering "what happened, and why?" quickly.