---
title: Skill Evaluation
description: Test what an agent can do — tool selection, proficiency, and correctness.
---

**Skill evaluation** tests whether an agent can perform its job by selecting the right tools, using them proficiently, and producing correct results.

## What it tests

- Does the agent select the appropriate tool for the task?
- Does it use the tool correctly (proper arguments, error handling)?
- Does it achieve the desired outcome?
- Does proficiency match the expected level?

## Scorer: `skill_usage`

The `skill_usage` scorer evaluates tool selection and usage by analyzing the agent's run trace:

```go
testcase.ScorerConfig{
    Name: "skill_usage",
    Config: map[string]any{
        "expected_tools":  []string{"read_file", "search_code"},
        "proficiency_min": 0.7,
    },
}
```

The scorer examines the `RunTrace` to check which tools were called, in what order, and whether the arguments were well-formed.

## Scenario: `skill_challenge`

The `skill_challenge` scenario generator creates test cases that require the agent to select and use specific tools:

```go
Case{
    ScenarioType: testcase.ScenarioSkillChallenge,
    Input:        "Find all security vulnerabilities in the auth module",
    Context: map[string]any{
        "available_tools": []string{"read_file", "search_code", "run_tests"},
        "expected_tools":  []string{"search_code", "read_file"},
    },
}
```

## Dimension score

The skill dimension contributes to the `DimensionScores` map on both `Result` and `Run`:

```go
result.DimensionScores["skill"] // 0.0 to 1.0
```

## Use cases

- Verify a code review agent uses `search_code` before `read_file`
- Test that a data analyst agent selects the right database query tools
- Ensure a customer support agent escalates correctly when tools fail