eval-harness

Define and run capability/regression evals for Claude Code sessions with pass@k metrics.

Updated Aug 23, 2026
One-click install
npx skills add https://github.com/ssrxs/scx-studio-pro-fixed --skill eval-harness-ssrxs
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: eval-harness
Source: https://github.com/ssrxs/scx-studio-pro-fixed/tree/main/gemini-skills/ecc-eval-harness
Command: npx skills add https://github.com/ssrxs/scx-studio-pro-fixed --skill eval-harness-ssrxs

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This skill provides a formal evaluation framework designed to structure eval-driven development for Claude Code sessions, enabling repeatable, rigorous assessment of AI behavior and reliability.

Core Features & Use Cases

  • Eval Types: Capability Evals and Regression Evals to define success criteria and verify behavior across iterations.
  • Grader Types: Code-Based Grader, Model-Based Grader, and Human Grader for deterministic, evaluative, and manual review paths.
  • Metrics & Workflow: pass@k and pass^k metrics, and a four-phase workflow (Define, Implement, Evaluate, Report) to track quality over time.
  • Use Case: Use this framework to establish regression tests for Claude Code tasks, measure reliability across model versions, and maintain a living eval suite.

Quick Start

Define evaluation goals, implement eval definitions, run the eval suite, and review results.

Frequently Asked Questions about eval-harness

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

FAQPage Schema
How do I set up an eval-driven development workflow for Claude Code sessions?

Set up an eval-driven workflow by defining capability and regression evals, implementing pass/fail criteria, running the eval suite, and reviewing results through a four-phase workflow: Define, Implement, Evaluate, Report.

What is the difference between capability and regression evals in Claude Code evaluation?

Capability evals define success criteria to assess AI behavior, while regression evals verify that behavior remains consistent across model iterations. Both are needed to track quality and reliability over time.

How do pass@k and pass^k metrics work for benchmarking Claude Code model performance?

Pass@k and pass^k metrics measure model reliability by evaluating successful task completion rates across multiple attempts. These metrics track quality and benchmark performance across different model versions.

What grader types are available for defining pass/fail criteria in Claude Code evaluation?

The framework supports three grader types: Code-Based Graders for deterministic checks, Model-Based Graders for automated evaluative scoring, and Human Graders for manual review paths.

Can I use this evaluation framework to maintain regression tests for Claude Code tasks?

Yes, you can use this framework to establish regression tests for Claude Code tasks, measure reliability across model versions, and maintain a living eval suite for continuous quality tracking.

What are the limitations of using a formal evaluation framework for Claude Code sessions?

This framework requires predefined functional requirements and success criteria before execution. It is structured for rigorous assessment, meaning ad-hoc or undefined Claude Code tasks cannot be reliably evaluated without prior setup.