eval-harness

Implements eval-driven development with pass/fail criteria and pass@k metrics for AI coding sessions.

Updated Jul 16, 2026
One-click install
npx skills add https://github.com/pjherron/hypoc --skill eval-harness-pjherron
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: eval-harness
Source: https://github.com/pjherron/hypoc/tree/main/hypoc/skills/eval-harness
Command: npx skills add https://github.com/pjherron/hypoc --skill eval-harness-pjherron

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? AI-assisted coding lacks objective quality gates, making it hard to know whether an agent's output actually works or whether a prompt change broke existing behavior. This Skill provides a formal evaluation framework that treats evals as unit tests for AI development. ## Core Features & Use Cases - Capability and Regression Evals: Define expected behavior before implementation and verify existing functionality stays intact after changes. - Multiple Grader Types: Use deterministic code graders, model-based LLM-as-judge rubrics, or human review flags depending on the output type. - Reliability Metrics: Track pass@k and pass^k metrics with recommended thresholds (pass@3 >= 0.90 for capability, pass^3 = 1.00 for release-critical paths). - Use Case: Before adding authentication to an app, define capability evals (registration, login, session persistence) and regression evals (public routes, API responses), then run evals after implementation and generate a structured pass/fail report. ## Quick Start Ask the agent to define an eval for a new feature with pass/fail criteria before writing any implementation code.

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 eval-driven development for AI coding agents?▼

Define capability and regression evals before writing code, specifying concrete pass/fail criteria for each behavior. Run the evals during and after implementation, then generate a report tracking pass@k metrics to decide if the change is ready to ship.

What is the difference between pass@k and pass^k metrics?▼

pass@k measures whether at least one of k attempts succeeds, indicating practical reliability under retries. pass^k requires all k attempts to succeed, making it a stricter stability test recommended for release-critical regression paths.

When should I use a code grader versus a model grader?▼

Use code graders for deterministic checks like grep patterns, test suites, or build success since they are fast and reproducible. Use model graders for open-ended outputs requiring judgment, and human graders for security-sensitive or ambiguous changes.

What pass rate thresholds should AI agent evals meet?▼

The recommended thresholds are pass@3 of at least 0.90 for capability evals and pass^3 of 1.00 for regression evals on release-critical paths. These balance practical reliability against the cost of retries.

What are common eval anti-patterns to avoid?▼

Avoid overfitting prompts to known eval examples, measuring only happy-path outputs, ignoring cost and latency drift, and allowing flaky graders in release gates. Evals should be versioned with code and kept fast so they actually get run.