eval-harness

Implement eval-driven development workflows for Claude Code with pass@k tracking.

1|Updated Mar 3, 2026
One-click install
npx skills add https://github.com/samymity/bridge-ventures-backend --skill eval-harness-samymity
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: eval-harness
Source: https://github.com/samymity/bridge-ventures-backend/tree/main/.claude/skills/eval-harness
Command: npx skills add https://github.com/samymity/bridge-ventures-backend --skill eval-harness-samymity

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

It helps teams define and run repeatable evaluation checks for Claude Code behavior so reliability and regressions can be measured instead of guessed.

Core Features & Use Cases

  • Capability Evals for New Behavior: Create evals that verify Claude can accomplish newly implemented capabilities using explicit success criteria.
  • Regression Evals for Stability: Preserve existing functionality by running baseline comparisons and tracking X/Y pass results over time.
  • Multi-Mode Grading: Use deterministic code-based graders, rubric-based model graders, and human review gates for high-risk or ambiguous outputs.

Quick Start

Create a new eval definition and include success criteria for what Claude must achieve, then run and record the resulting PASS/FAIL outcomes for capability and regression coverage.

Frequently Asked Questions about eval-harness

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

FAQPage Schema
How do I run regression testing for LLM reliability in Claude Code?

Run regression testing for LLM reliability by defining baseline capability checks and tracking X/Y pass results over iterative prompt changes. This eval-driven workflow records PASS/FAIL outcomes to prevent regressions.

What is eval-driven development and how does it measure prompt quality?

Eval-driven development measures prompt quality by applying explicit success criteria to AI outputs. It uses deterministic code-based graders, rubric-based model graders, and human review gates to quantify agent reliability and pass@k metrics.

How do I define capability evals for new AI agent behavior?

Define capability evals by creating a YAML-identified skill entry with explicit success criteria for what Claude must achieve. Run the checks and record the resulting PASS/FAIL outcomes to verify newly implemented capabilities.

What grading methods can I use to evaluate LLM outputs?

You can evaluate LLM outputs using multi-mode grading: deterministic code-based graders for strict checks, rubric-based model graders for subjective quality, and human review gates for high-risk or ambiguous outputs.

How do I track pass@k reliability across iterative prompt or agent changes?

Track pass@k reliability by running repeatable evaluation checks and generating eval reports that record X/Y pass results over time. This workflow measures stability and prevents regressions across iterative changes.

Do I need external dependencies to set up an eval harness for Claude Code?

No external dependencies are required to set up an eval harness for Claude Code. The workflow relies on a YAML-identified skill entry plus instruction-driven patterns for eval definitions, grader types, metrics, and storage layout.