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

# Evaluation

> Measure and improve agent performance

Evaluation measures how well your agents perform, helping you improve over time.

```mermaid theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
graph LR
    subgraph "Evaluation Loop"
        A[🤖 Agent] --> O[📤 Output]
        O --> E[📊 Evaluate]
        E --> S[📈 Score]
        S --> I[🔧 Improve]
        I --> A
    end
    
    classDef agent fill:#6366F1,stroke:#7C90A0,color:#fff
    classDef eval fill:#F59E0B,stroke:#7C90A0,color:#fff
    classDef result fill:#10B981,stroke:#7C90A0,color:#fff
    
    class A agent
    class O,E,S eval
    class I result
```

## Quick Start

<Steps>
  <Step title="Evaluate Response">
    ```rust theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
    use praisonai::{Agent, AccuracyEvaluator};

    let agent = Agent::new().name("Assistant").build()?;
    let evaluator = AccuracyEvaluator::new();

    let response = agent.chat("What is 2+2?").await?;
    let score = evaluator.evaluate(&response, "4");

    println!("Accuracy: {:.1}%", score.value * 100.0);
    ```
  </Step>

  <Step title="Multiple Criteria">
    ```rust theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
    use praisonai::CriteriaEvaluator;

    let evaluator = CriteriaEvaluator::new()
        .criterion("clarity", "Is the response clear?")
        .criterion("accuracy", "Is the response accurate?")
        .build();

    let scores = evaluator.evaluate(&response);
    ```
  </Step>
</Steps>

***

## Evaluator Types

| Evaluator              | Measures                 |
| ---------------------- | ------------------------ |
| `AccuracyEvaluator`    | Correctness vs expected  |
| `CriteriaEvaluator`    | Multiple custom criteria |
| `PerformanceEvaluator` | Speed and efficiency     |
| `Judge`                | LLM-as-judge scoring     |

***

## Best Practices

<AccordionGroup>
  <Accordion title="Test on diverse examples">
    Use varied test cases to get accurate evaluation.
  </Accordion>

  <Accordion title="Iterate based on scores">
    Low scores indicate where to improve prompts or tools.
  </Accordion>
</AccordionGroup>

***

## Related

<CardGroup cols={2}>
  <Card title="Optimizer" icon="wand-sparkles" href="/docs/rust/optimizer">
    Auto-improve agents
  </Card>

  <Card title="Tracing" icon="chart-line" href="/docs/rust/tracing">
    Performance tracing
  </Card>
</CardGroup>