The quick read
- Validate structure in code and evaluate field accuracy against representative examples.
- Request only fields the application uses.
Identify the consumer
Free text fits explanations and open-ended discussion. Structured output fits systems that need named fields, predictable types or a constrained set of values. Format validity and factual validity are separate checks: a perfectly formed object can still contain the wrong date or an unsupported claim.
Test both layers
Validate structure in code and evaluate field accuracy against representative examples. Decide how the application represents missing information and uncertainty. Avoid forcing the model to fill a field with a guess when the source contains no answer.
Choose the smallest contract
Request only fields the application uses. Keep provenance when it matters and reject invalid outputs safely. Add human-readable explanation where it helps the user assess a decision, rather than embedding long narrative inside fields designed for precise values.
Sources & notes
An editorial decision framework, not a scored benchmark or hands-on test.
developers.openai.com — official reference
developers.openai.com — official reference
Sources reviewed for the September 2026 launch edition.