Junior interview question
Your API's JSON mode is on. In what ways can an output still break the code that reads it?
Model answer
JSON mode guarantees valid JSON, not its content. Output can still be cut off at the output-token limit, which doesn't parse. And parseable outputs can still carry wrong types ("2" for an integer), invented labels, missing or extra fields, or values past a limit. Only a schema check catches those.
Practise the rest
10 Structured outputs questions, 492 in all, each with a model answer. Free.
More Structured outputs interview questions
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- Your few-shot sentiment prompt lists six positive examples, then two negative ones at the very end. What's the risk, and what would you do?
- You add a repair step that keeps the first JSON object and closes open braces. Nearly every output now parses, but half are still invalid. Why?
- Each attempt gives valid output 90% of the time. A colleague proposes up to three attempts to reach 99.9%. What do you say?
- Where in the stack can you push a model towards a format, and what would you use for a classifier that must never invent a label?
- Zero-shot or few-shot prompting: what's the difference, and when do you add examples?