eval-harness

Define and run structured evals for Claude Code sessions with pass@k metrics.

1|Updated Mar 6, 2026
One-click install
npx skills add https://github.com/khetansarvesh/ai_skills_repo --skill eval-harness-khetansarvesh
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: eval-harness
Source: https://github.com/khetansarvesh/ai_skills_repo/tree/main/skills/eval-harness
Command: npx skills add https://github.com/khetansarvesh/ai_skills_repo --skill eval-harness-khetansarvesh

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Eval-driven development needs a repeatable way to define expected behavior, run checks, and detect regressions in Claude Code sessions instead of relying on subjective impressions of quality.

Core Features & Use Cases

  • Capability Evals: Verify Claude can complete specific new tasks and meets explicit success criteria, making improvements measurable.
  • Regression Evals: Ensure changes do not break existing workflows by comparing results against a known baseline.
  • Multiple Grader Modes: Support deterministic code-based checks, model-based rubric scoring, and optional human adjudication for ambiguous or sensitive outcomes.

Use Case Examples: benchmarking agent reliability across model versions, creating prompt or agent change regression suites, and producing structured reports with pass@k and pass^k metrics for release readiness.

Quick Start

Create an eval definition for a feature, then run and report results with the commands: /eval define feature-name, /eval check feature-name, and /eval report feature-name.

Frequently Asked Questions about eval-harness

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
What is eval-driven development for AI agents?▼

Eval-driven development is a methodology that reduces uncertainty in AI-assisted development by defining formal evaluation frameworks with explicit success criteria to measure agent reliability. It replaces subjective impressions with repeatable checks for capability testing and regression detection.

How do I set up regression testing for Claude Code prompt iterations?▼

To set up regression testing, you define an eval with explicit success criteria, then run the checks against a known baseline using code, model, or human graders. This detects workflow regressions during prompt or agent iterations.

How do pass@k and pass^k metrics work for LLM benchmarking?▼

Pass@k and pass^k are reliability metrics used in LLM benchmarking to measure AI consistency across attempts. They are generated by running structured evals with code or model graders, producing artifact-style logs for release readiness.

Can I use an LLM-as-judge grader for ambiguous AI outputs?▼

Yes, you can use model-based rubric scoring as an LLM-as-judge grader for ambiguous outcomes. The framework supports deterministic code-based checks, model-based grading, and optional human adjudication for sensitive results.

What's the best way to benchmark agent reliability across model versions?▼

The best way to benchmark agent reliability is implementing structured capability evals with explicit success criteria, then running them across model versions to compare pass@k metrics against a baseline. This makes improvements measurable.