9 min readUpdated September 22, 2026
How to debug an AI-built app
A repeatable method: reproduce it, read the real error, find the layer, change one thing, verify. Written for apps whose code you did not type.
Troubleshooting
Symptom-first guides: what the error means, what caused it, how to check, and how to know it is really fixed.
8 min readUpdated September 22, 2026
How to troubleshoot an AI-built application
A symptom-to-cause index. Start from what you can see — a blank page, an empty list, a failed login, a dead deploy — and follow it to the layer responsible.
7 min readUpdated September 22, 2026
Why am I getting a 401 error?
A 401 means the server could not identify you. The causes, how to tell which one you have, and how to confirm the fix.
8 min readUpdated September 22, 2026
Why does my app work locally but not after deployment?
The differences between your machine and a deployment — configuration, case sensitivity, build strictness, real users — and how to find which one bit you.
8 min readUpdated September 22, 2026
Why can't my frontend access my database?
Empty lists, permission errors and silent failures between the browser and a hosted database — and how to tell which of the three you have.
6 min readUpdated September 22, 2026
Why isn't my environment variable working?
The variable is set and the code still reads undefined. The six reasons that happens, in the order worth checking them.
7 min readUpdated September 22, 2026
Why is my API key exposed?
How keys end up visible in a bundle or a repository, how to confirm it, what to do in the first ten minutes, and how to stop it recurring.
6 min readUpdated September 22, 2026
Why isn't my GitHub deployment updating?
Your change is committed and the live site is unchanged. Branch, build, cache or domain — how to find out which, in four checks.
7 min readUpdated September 22, 2026
Why is my AI API returning 429?
Rate limits, token limits, concurrency limits and accidental loops — how to tell which one you hit and how to stop hitting it.
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