How to Make AI Return Valid JSON Every Time
AI models return broken JSON more often than you'd expect. Here's how to structure a prompt so the output parses cleanly, plus what to check before you trust it.
Explore all 9 guides related to JSON Output Prompt Builder.
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AI models return broken JSON more often than you'd expect. Here's how to structure a prompt so the output parses cleanly, plus what to check before you trust it.
The AI nails your format once, then the next output adds a "Sure, here's…" wrapper, renames a field, turns the table into bullets, and drops a section. Here's how to write the format as a contract and catch the drift when it happens anyway.
AI pulls the fields you asked for, but hands back a flat list with no way to tell which values it read from the document and which it guessed. Here's how to make each extracted value carry its source quote, location, and a review flag — so you can check the result instead of trusting it.
Give AI several sources and it pours them into one bowl — attributing Source A's claim to Source B, averaging a real conflict into a smooth "customers generally think," and calling it consensus. Here's how to keep each source separate and attributed so the facts stay traceable to where they came from.
AI extraction returns clean JSON that quietly means something different each run. Design the extraction schema first — each field's meaning, type, allowed values, missing-value rule, and required evidence — and review it before a single record is pulled.
Ask AI to extract fields with "use null if missing" and one null means missing, false, a stated "none", and a real zero — valid JSON, wrong meaning. Handle unknown vs empty vs not-applicable in AI output: give each field a value state so absence gets classified, not collapsed.
Paste a messy export and "classify these rows" and the AI splits one bug into three categories, mixes currencies, and counts three duplicate rows as three problems — silently. Normalize messy inputs before AI processes them: standardize the formats and flag the ambiguous cases.
You ask AI to fill a table — issue_type, priority, reason — and the same column gets filled by different logic each row: priority as urgency here, sentiment there. Here's how to define each field's meaning, allowed values, and include/exclude rules so AI fills them consistently.
An endpoint exists but its docs don't, so "document this API" from code alone invents parameters, status codes, and an auth flow that were never real. Here's how to write API documentation with AI from the facts you provide, with unknowns flagged and checked against the real API.