Asked about Validating at the boundary
Why is model output untrusted input?
An answer that works
It is generated rather than guaranteed. It is usually the shape you asked for and sometimes is not, and a schema only guarantees structure, never that the values are real. Treat it like a form submission from a stranger.
Reading an answer is not being able to give one. The section that teaches this is Validating at the boundary, 6 hours of Typing & validation.
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