If you've ever pasted a single JSON object into a "json to typescript" tool and gotten back a clean interface, only to have your API return a slightly different shape the next day and blow up your build — you've hit the single-sample problem. It's the most common, least talked-about failure mode in JSON-to-TypeScript conversion, and it's worth understanding before you trust any generated type in a real codebase.
What "generate TypeScript types from JSON" actually means
At its core, converting JSON to TypeScript is a structural mapping exercise. JSON has a small set of value types — string, number, boolean, null, array, object — and each one has an obvious TypeScript counterpart:
{
"id": 42,
