Study operating system
How to complete the course and retain a real result
1. Start from the contract
For every AI feature, define the input/output schema, timeout budget, retry policy, idempotency key, error taxonomy, and authoritative source first. A prompt without a transport and application contract is not yet a backend.
2. Reproduce failure
Add timeout, provider 429/5xx, malformed structured output, duplicate request, client cancellation, and stale retrieval to the happy path. Every failure must end in a predictable system state.
3. Verify the side effect
If the model proposes a tool action, the application layer independently verifies identity, authority, schema, preconditions, and idempotency. Model text is not permission to execute an action.
4. Capture production evidence
Record traces, latency, retries, retrieval evidence, tool decisions, cost per successful task, and regression results. “It answered locally” is a remarkably modest observability stack.