---
title: EvaluationSubject
framework: evaluations
role: symbol
role_heading: Protocol
path: evaluations/evaluationsubject
---

# EvaluationSubject

A type that represents the output produced by the system under test.

## Declaration

```swift
protocol EvaluationSubject<Value>
```

## Overview

Overview Conform to this protocol to define custom subject types. The primary concrete conformance is ModelSubject, which carries a value and an optional transcript for tool-call evaluation. struct MySubject<Value: Codable>: EvaluationSubject {     var value: Value     var transcript: StructuredTranscript? }

## Topics

### Associated Types

- [Value](evaluations/evaluationsubject/value-swift.associatedtype.md)

### Instance Properties

- [value](evaluations/evaluationsubject/value-swift.property.md)

## Relationships

### Conforming Types

- [ModelSubject](evaluations/modelsubject.md)

## See Also

### Testing an intelligent feature

- [Subject](evaluations/evaluation/subject.md)
- [subject(from:)](evaluations/evaluation/subject(from:).md)
- [ModelSubject](evaluations/modelsubject.md)
- [name](evaluations/evaluation/name.md)