eval_builder

Generate eval.md evaluation criteria with test cases and run instructions.

7|Updated May 6, 2026
One-click install
npx skills add https://github.com/tya5/reyn --skill eval-builder
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: eval_builder
Source: https://github.com/tya5/reyn/tree/main/src/reyn/stdlib/skills/eval_builder
Command: npx skills add https://github.com/tya5/reyn --skill eval-builder

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

It automates the creation of detailed evaluation specifications (eval.md) that assess a skill’s correctness and quality.

Core Features & Use Cases

  • Criteria Generation: Designs specific, evidence-bound quality criteria for each phase of a skill’s workflow.
  • Test Case Design: Creates representative test cases that probe typical, edge, and failure scenarios.
  • Use Case: Facilitates objective assessment of skill outputs by generating a comprehensive eval.md file aligned with phases and criteria, enabling consistent performance measurement.

Quick Start

Invoke the eval_builder skill to generate an eval specification for a given skill name.

Frequently Asked Questions about eval_builder

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

FAQPage Schema
How do I generate evaluation criteria for testing a skill's performance?▼

To generate evaluation criteria for testing skill performance, you can use an automated eval builder that creates a detailed eval.md document containing specific test cases, quality standards, and run instructions for objective assessment.

What is an eval.md specification and when do I need one for assessment?▼

An eval.md specification is a document containing evidence-bound quality criteria and test cases for assessing skill correctness. You need one when you want to objectively measure and verify skill behavior across typical and edge scenarios.

How do I create test cases that cover edge scenarios for skill evaluation?▼

You can create test cases for edge scenarios by designing an evaluation specification that probes typical, edge, and failure conditions, producing observable, criterion-based verification of skill behavior and referencing existing artifacts when available.

Can I evaluate skill outputs without writing manual quality standards?▼

Yes, you can evaluate skill outputs without manual standards by automating criteria generation. The tool designs specific, evidence-bound quality criteria for each workflow phase, enabling consistent performance measurement without manual specification writing.

What is the best way to structure run instructions for skill assessment?▼

The best way to structure run instructions for skill assessment is to align them with workflow phases and quality criteria within a comprehensive eval.md document, ensuring consistent performance measurement and observable verification of skill behavior.