Human review output format: string vs JSON - Braintrust

Applies to:

• Plan - Any
• Deployment - Any
• Use case - Understanding how human review values are stored in the expected field

Summary

Behavior: When labeling samples with human review, the value written to the expected field format depends on the number of reviews applied to the row.

Expected field formats

Single human review

When only one human review is configured, the output is a plain string:

"pass"

Multiple human reviews

When two or more human reviews are configured, all values are stored as JSON:

{
  "review name": "pass",
  "second review": "value"
}

Working with different formats

Force JSON format

To ensure consistent JSON output, add a second human review to your project and apply both reviews to each row.

Manual expected field updates

You can manually edit the expected field in the UI to convert between string and JSON formats as needed.

Notes

• This behavior is consistent across human review configurations
• The format is determined when the review is submitted and cannot be changed through project settings
• See the human review guide for general configuration reference.