---
title: EvaluatorError
framework: evaluations
role: symbol
role_heading: Enumeration
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: evaluations/evaluatorerror
---

# EvaluatorError

A typed reason why an evaluator failed while scoring a produced subject.

## Declaration

```swift
enum EvaluatorError
```

## Overview

Overview Recorded in the detailed DataFrame’s EvaluatorErrors column (as an array, since multiple evaluators can fail for one sample). Distinct from SubjectInferenceError so each failure mode can grow its own cases independently.

## Topics

### Enumeration Cases

- [EvaluatorError.failed(evaluator:evaluatorType:reason:)](evaluations/evaluatorerror/failed(evaluator:evaluatortype:reason:).md)

## Relationships

### Conforms To

- [Error](swift/error.md)
- [LocalizedError](foundation/localizederror.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Errors

- [EvaluationError](evaluations/evaluationerror.md)
- [SubjectInferenceError](evaluations/subjectinferenceerror.md)
- [EvaluationResultsError](evaluations/evaluationresultserror.md)