> ## Documentation Index
> Fetch the complete documentation index at: https://docs.neuraltrust.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Equals

The Equals Evaluator is a specialized tool designed to perform exact string matching between a response and an expected output. It provides a binary evaluation where the response must match the expected output exactly to pass.

## Purpose

The Equals Evaluator is particularly useful when you need to:

* Verify exact string matches
* Ensure responses match predefined templates
* Validate fixed-format outputs
* Check for precise command or code outputs
* Test exact response requirements

## How It Works

The evaluator uses a simple binary scoring system:

* **Score: 1**: The response exactly matches the expected output
* **Score: 0**: The response does not match the expected output

The evaluation is strict and case-sensitive, requiring an exact character-by-character match between the response and the expected output.

## Usage Example

```python theme={null}
import asyncio

from trusttest.evaluation_contexts import ExpectedResponseContext
from trusttest.evaluators import EqualsEvaluator


async def evaluate():
    evaluator = EqualsEvaluator()
    result = await evaluator.evaluate(
        response="Hello, World!",
        context=ExpectedResponseContext(
            expected_response="Hello, World!"
        )
    )
    print(result)

if __name__ == "__main__":
    asyncio.run(evaluate())
```

The evaluator returns a tuple containing:

* A binary score (0 or 1) indicating exact match status
* A list of explanations including:
  * Success message if matched
  * Failure message with both expected and received responses if not matched

## When to Use

Use the Equals Evaluator when you need to:

* Verify exact command outputs
* Validate fixed-format responses
* Check for precise string matches
* Test template-based responses
* Ensure exact compliance with specifications
* Validate code snippets or commands