Skill Grader

Name: Skill Grader
Author: erichowens

erichowens/some_claude_skills

94 installs
178 repo stars
Updated July 14, 2026
erichowens/some_claude_skills

Evaluate Claude skills on 10 quality axes with letter grades and improvement recommendations.

About

Structured rubric for assessing skill quality covering description, scope, progressive disclosure, clarity, completeness, and impact. Produces A+ through F grades with specific fixes per axis.

10 evaluation axes with 2x weights on description and scope
Improvement roadmap for prioritizing skill enhancements

Skill Grader by the numbers

94 all-time installs (skills.sh)
Ranked #266 of 782 Skill Development skills by installs in the Skillselion catalog
Data as of Aug 4, 2026 (Skillselion catalog sync)

npx skills add https://github.com/erichowens/some_claude_skills --skill skill-grader

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[![Listed on Skillselion](https://skillselion.com/badge/skills/erichowens/some_claude_skills/skill-grader.svg)](https://skillselion.com/skills/erichowens/some_claude_skills/skill-grader)

Installs	94
repo stars	★ 178
Last updated	July 14, 2026
Repository	erichowens/some_claude_skills ↗

What it does

Evaluate Claude skills on 10 quality axes with letter grades and improvement recommendations.

Files

SKILL.mdMarkdownGitHub ↗

Skill Grader

Structured evaluation rubric for Claude Agent Skills. Produces letter grades (A+ through F) on 10 axes plus an overall grade, with specific improvement recommendations for each axis.

Designed for sub-agents and non-expert reviewers who need a mechanical, repeatable process for assessing skill quality without deep domain expertise.

---

When to Use

✅ Use for:

Auditing a single skill's quality
Comparing skills against each other
Prioritizing which skills to improve first
Quality control sweeps across a skill library
Generating improvement roadmaps

❌ NOT for:

Creating new skills (use skill-architect)
Grading code quality or non-skill documents
Evaluating agent performance (different from skill quality)

---

Grading Process

flowchart TD
  A[Read SKILL.md + all files] --> B[Score each of 10 axes]
  B --> C[Assign letter grade per axis]
  C --> D[Compute overall grade]
  D --> E[Write improvement recommendations]
  E --> F[Produce grading report]

Step-by-Step

1. Read the entire skill folder — SKILL.md, all references, scripts, CHANGELOG, README 2. Score each axis — Use the rubric below (0-100 per axis) 3. Convert to letter grade — See grade scale 4. Compute overall grade — Weighted average (Description and Scope are 2x weight) 5. Write 1-3 specific improvements per axis scoring below B+ 6. Produce the grading report in the output format below

---

The 10 Evaluation Axes

Axis 1: Description Quality (Weight: 2x)

Does the description follow [What] [When] [Keywords]. NOT for [Exclusions]?

Grade	Criteria
A	Specific verb+noun, domain keywords users would type, 2-5 explicit NOT exclusions, 25-50 words
B	Has keywords and NOT clause, but slightly vague or missing synonym coverage
C	Too generic, missing NOT clause, or >100 words of process detail
D	Single vague sentence ("helps with X") or name/description mismatch
F	Missing or empty description

Axis 2: Scope Discipline (Weight: 2x)

Is the skill narrowly focused on one expertise type, or a catch-all?

Grade	Criteria
A	One clear expertise domain, "When to Use" and "NOT for" sections both present and specific
B	Mostly focused, minor boundary ambiguity
C	Covers 2-3 related but distinct domains, should probably be split
D	Catch-all skill ("helps with anything related to X")
F	No scope boundaries defined at all

Axis 3: Progressive Disclosure

Does the skill follow the three-layer architecture (metadata → SKILL.md → references)?

Grade	Criteria
A	SKILL.md <300 lines, heavy content in references, reference index in SKILL.md with 1-line descriptions
B	SKILL.md <500 lines, some references used, index present
C	SKILL.md >500 lines, or all content inlined with no references
D	SKILL.md >800 lines, or references exist but aren't indexed in SKILL.md
F	Single massive file with no structure

Axis 4: Anti-Pattern Coverage

Does the skill encode expert knowledge that prevents common mistakes?

Grade	Criteria
A	3+ anti-patterns with Novice/Expert/Timeline template, LLM-mistake notes
B	1-2 anti-patterns with clear explanation
C	Anti-patterns mentioned but no structured template
D	No anti-patterns, just positive instructions
F	Contains advice that IS an anti-pattern (outdated, harmful)

Axis 5: Self-Contained Tools

Does the skill include working tools (scripts, MCPs, subagents)?

Grade	Criteria
A	Working scripts with CLI interface, error handling, dependency docs; OR valid "no tools needed" justification
B	Scripts exist and work but lack error handling or docs
C	Scripts referenced but are templates/pseudocode
D	Phantom tools (SKILL.md references files that don't exist)
F	References non-existent tools AND no acknowledgment

Note: Not every skill needs tools. A pure decision-tree skill can score A if tools aren't applicable.

Axis 6: Activation Precision

Would the skill activate correctly on relevant queries and stay silent on irrelevant ones?

Grade	Criteria
A	Description has specific keywords matching user language, clear NOT clause, no obvious false-positive vectors
B	Good keywords, minor false-positive risk
C	Generic keywords that overlap with other skills
D	No specific keywords, or NOT clause contradicts intended use
F	Description would cause constant false activation

Axis 7: Visual Artifacts

Does the skill use Mermaid diagrams, code examples, and tables effectively?

Grade	Criteria
A	Decision trees as Mermaid flowcharts, tables for comparisons, code examples for concrete patterns
B	Some diagrams or tables, but key decision trees still in prose
C	Tables used but no Mermaid diagrams for processes
D	Prose-only, no visual structure
F	Wall of text with no formatting aids

Axis 8: Output Contracts

Does the skill define what it produces in a format consumable by other agents?

Grade	Criteria
A	Explicit output format (JSON schema, markdown template, or structured sections), subagent-consumable
B	Output format implied but not explicitly documented
C	No output format, but content is structured enough to infer
D	Unstructured prose output expected
F	N/A (pure reference skill) — exempt from this axis

Axis 9: Temporal Awareness

Does the skill track when knowledge was current and what has changed?

Grade	Criteria
A	Timelines in anti-patterns, "as of [date]" markers, CHANGELOG with dates
B	Some temporal context, CHANGELOG exists
C	No dates on knowledge, but CHANGELOG exists
D	No temporal context anywhere, knowledge could be stale
F	Contains demonstrably outdated advice without warning

Axis 10: Documentation Quality

README, CHANGELOG, and reference organization.

Grade	Criteria
A	README with quick start, CHANGELOG with dated versions, references well-organized with clear filenames
B	README and CHANGELOG exist, references present
C	SKILL.md is the only file, but it's well-structured
D	No README, no CHANGELOG, disorganized references
F	SKILL.md is the only file and it's poorly structured

---

Grade Scale

Letter	Score Range	Meaning
A+	97-100	Exemplary — sets the standard
A	93-96	Excellent — minor improvements possible
A-	90-92	Very good — a few small gaps
B+	87-89	Good — notable room for improvement
B	83-86	Solid — several areas need work
B-	80-82	Above average — meaningful gaps
C+	77-79	Average — significant improvements needed
C	73-76	Below average — major gaps
C-	70-72	Barely adequate
D+	67-69	Poor — fundamental issues
D	63-66	Very poor — needs major rework
D-	60-62	Near-failing quality
F	<60	Failing — start over

---

Overall Grade Computation

Axes 1 (Description) and 2 (Scope) carry 2x weight. All others carry 1x weight. If Axis 8 (Output Contracts) is marked exempt, remove it from the calculation.

Overall = (2×Axis1 + 2×Axis2 + Axis3 + Axis4 + Axis5 + Axis6 + Axis7 + Axis8 + Axis9 + Axis10) / 12

Convert the numeric average to a letter grade using the scale above.

---

Output Format

Produce this exact structure:

# Skill Grading Report: [skill-name]

**Graded**: [date]
**Overall Grade**: [letter] ([score]/100)

## Axis Grades

| # | Axis | Grade | Score | Key Finding |
|---|------|-------|-------|-------------|
| 1 | Description Quality | [grade] | [score] | [1-line finding] |
| 2 | Scope Discipline | [grade] | [score] | [1-line finding] |
| 3 | Progressive Disclosure | [grade] | [score] | [1-line finding] |
| 4 | Anti-Pattern Coverage | [grade] | [score] | [1-line finding] |
| 5 | Self-Contained Tools | [grade] | [score] | [1-line finding] |
| 6 | Activation Precision | [grade] | [score] | [1-line finding] |
| 7 | Visual Artifacts | [grade] | [score] | [1-line finding] |
| 8 | Output Contracts | [grade] | [score] | [1-line finding] |
| 9 | Temporal Awareness | [grade] | [score] | [1-line finding] |
| 10 | Documentation Quality | [grade] | [score] | [1-line finding] |

## Top 3 Improvements (Highest Impact)

1. **[Axis]: [Specific action]** — [Why this matters, expected grade improvement]
2. **[Axis]: [Specific action]** — [Why this matters, expected grade improvement]
3. **[Axis]: [Specific action]** — [Why this matters, expected grade improvement]

## Detailed Notes

### [Axis name] ([grade])
[2-3 sentences of specific feedback with examples from the skill]

[Repeat for each axis scoring below B+]

---

Quick Grading (Abbreviated)

For rapid triage across many skills, produce only:

| Skill | Overall | Desc | Scope | Disc | Anti | Tools | Activ | Visual | Output | Temp | Docs |
|-------|---------|------|-------|------|------|-------|-------|--------|--------|------|------|
| [name] | [grade] | ... | ... | ... | ... | ... | ... | ... | ... | ... | ... |

---

Anti-Patterns in Grading

Grade Inflation

Wrong: Giving B+ because "it's pretty good" without checking criteria. Right: Match observations to the rubric table literally. If the description lacks a NOT clause, it cannot score above C on Axis 1.

Missing Context

Wrong: Grading a pure decision-tree skill poorly on Axis 5 (tools) because it has no scripts. Right: Mark Axis 5 as "A — tools not applicable for this skill type."

Ignoring Phantoms

Wrong: Scoring Axis 5 as B because scripts are "referenced." Right: Actually check if every referenced file exists. If scripts/validate.py is mentioned but doesn't exist, that's D.