halfmoon-mind

Rubric Evaluator — Development skill for Claude Code

Development community

Evaluate Claude Code and Codex skill directories with deterministic rubric checks and graded, fixable reports.

How to install Rubric Evaluator

This entry records only its repository, not the path inside it, so there is no exact command to give. Open halfmoon-mind/rubric-evaluator and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

What Rubric Evaluator does

Evaluate Claude Code and Codex skill directories with deterministic rubric checks and graded, fixable reports.

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README

Rubric Evaluator

![Rubric Evaluator project image](assets/project-image.png)

Grade a skill directory (one that contains a `SKILL.md`) against a 6-section, 31-item rubric. Deterministic structural and safety checks run as a stdlib-only Python script; semantic checks are applied from a bundled rubric reference. The headline grade (S/A/B/C/F) is computed deterministically, never eyeballed.

The rubric is based on Toss Tech's article [Skill 품질 관리를 위한 Rubric 설계와 시스템 구현](https://toss.tech/article/skill-quality-rubric).

The same skill bundle ships for two hosts from one source of truth at `plugins/rubric-evaluator/`:

Claude Code — .claude-plugin/plugin.json + the marketplace at the repo root
Codex — .codex-plugin/plugin.json + .agents/plugins/marketplace.json

Install (Claude Code)

/plugin marketplace add halfmoon-mind/rubric-evaluator
/plugin install rubric-evaluator@rubric-evaluator

Then ask Claude to evaluate a skill, e.g. *"grade the skill directory at ./my-skill"*.

To try it without installing (single session, from a local checkout):

claude --plugin-dir ./plugins/rubric-evaluator

Install (Codex)

Add this repository as a Codex marketplace source, then install the plugin:

codex plugin marketplace add halfmoon-mind/rubric-evaluator
codex plugin add rubric-evaluator@rubric-evaluator

To install from a local checkout instead, add the repo root as the local marketplace source:

codex plugin marketplace add .
codex plugin add rubric-evaluator@rubric-evaluator

Start a new Codex thread after installing, then ask Codex to evaluate a skill, e.g. *"Use $rubric-evaluator to grade the skill directory at ./my-skill"*.

Usage

Point the skill at any directory that contains a `SKILL.md`. There is nothing to run by hand — describe what you want in natural language and the skill triggers on requests to grade, audit, review, dogfood, or improve a skill.

Example prompts: