---
title: "Can OpenAI Structured Outputs enforce rules between related fields?"  
description: "Can OpenAI Structured Outputs enforce rules between related fields?"  
author: "Björn Ólafsson"  
published: 2026-10-17  
updated: 2026-10-17  
canonical: https://www.mindstick.com/forum/162516/can-openai-structured-outputs-enforce-rules-between-related-fields  
category: "OpenAI API"  
tags: ["OpenAI API", "Structured Outputs", "data validation"]  
reading_time: 1 minute  

---

# Can OpenAI Structured Outputs enforce rules between related fields?

I’m using the OpenAI API to extract booking details into a structured response. Getting the expected field names and types is only part of the requirement: the checkout date must come after the check-in date, and the guest count must not exceed the selected room’s capacity.

With **[OpenAI Structured Outputs](https://www.mindstick.com/forum/162393/how-should-openai-strict-structured-outputs-handle-optional-fields)**, how much of that validation can belong in the schema, and how much needs to happen in application code?

- Can the supported schema express a comparison between two date fields?
- What about a rule that depends on information supplied in the prompt, such as room capacity?
- If the response matches the schema but fails a business rule, is a correction request a sensible approach, or should the application reject it outright?

I’m trying to separate **schema validation from business rules** before deciding what the integration can safely accept without human review. Examples of that boundary would be more useful than a basic JSON formatting walkthrough.


---

Original Source: https://www.mindstick.com/forum/162516/can-openai-structured-outputs-enforce-rules-between-related-fields

Copyright © MindStick Software Pvt. Ltd. This Markdown version is provided for developers, AI systems, and offline reading.