Make a fast-built app dependable

What you’ll be able to do

Review identity, data, secrets, and cost as one system.
Test unavailable-service and invalid-input behavior.
Create a short operational handoff.

Before you beginOne reviewed prototype or lab app from earlier lessons. Use a lab scope and fictional records. No additional service is required for a review-only exercise.

Get the idea

Happy paths are incomplete evidence

A demo may work for one valid request while failing on missing data, slow services, or denied access. Test the behaviors a real user would encounter before claiming readiness.

An operator needs a way to respond

Useful monitoring identifies a symptom and the action to take. Record who owns the app, where logs are available, and how to disable a faulty feature. Keep secrets and unnecessary personal content out of logs.

Cost is part of the design

Know which requests create billable activity and how you limit usage. A budget can notify you; it does not automatically stop resource usage. Model-call limits and authorized endpoints help bound an AI feature.

Try it yourself

List the app’s trust boundaries: browser, backend, identity provider, database, and model service where applicable.
Ask the assistant for failure tests tied to those boundaries. Select invalid input, denied access, timeout, duplicate action, and unavailable data cases.
Run the applicable tests locally or in your lab. A controlled mock is preferable to disrupting a shared service. Record the actual result.
Inspect logs for secrets and unnecessary input content. Check deployment settings, allowed origins, server-side authorization, and usage limits.
Produce a one-page handoff with known limitations, monitoring signals, owner, cost controls, rollback or disable steps, and cleanup.

Example · commands or prompt

Review this app for a small pilot.
Identify trust boundaries and unverified assumptions.
Propose tests for invalid input, unauthorized access, timeouts,
duplicates, and unavailable dependencies.
Review secret handling, data retention, logs, and usage limits.
Separate verified behavior from recommendations.

Check your resultYour checklist records evidence for each selected failure case and names any unresolved issue before a pilot.

Finish the lab

Remove test data and temporary diagnostics. Keep the handoff alongside the source so the next operator can repeat the checks.

Quick knowledge check

Does a spending budget replace rate limits on an AI endpoint?

Reveal the explanation

No. A budget can notify you about spending. Rate limits and usage controls constrain requests; they address a different part of the design.

Take this with you

Speed comes from repeatable checks, not from skipping them.

Go deeper

AI-assisted lesson · Reference links checked October 3, 2026. Exercises are teaching examples; they have not been executed against your Azure subscription.