mutation-review

Use when reviewing a PR's test quality via mutation testing. Runs Stryker on the diff, triages surviving mutants, and posts findings as a PR comment with inline annotations on changed lines.

Quality

93%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

93%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A tight, highly actionable workflow with concrete commands and clear sequencing, well within token budget. The only meaningful gap is the absence of an explicit error-recovery feedback loop around the batch PR-comment posting.

Dimension	Reasoning	Score
Conciseness	Lean and efficient with no padding or explanation of concepts Claude already knows; every line is actionable instruction ('A non-zero exit is expected when mutants survive — do not treat it as failure', 'Do exactly one pass. Do not edit code.').	5 / 5
Actionability	Fully executable commands throughout — 'npm run mutate:diff', 'git diff --merge-base origin main', and a fully formed 'gh api repos/$REPO/pulls/$PR/comments ...' invocation — plus a concrete decision rule for triaging survivors.	5 / 5
Workflow Clarity	A clear six-step sequence with checkpoints (step 3 stops when the report is absent; step 2 flags the expected non-zero exit), but it lacks an explicit validate-fix-retry feedback loop for the batch comment-posting operations.	4 / 5
Progressive Disclosure	A well-organized single-file skill under 50 lines with clear sections (Inputs, Workflow, commands) and no external references, satisfying the simple-skill exception for progressive disclosure.	5 / 5
	Total	19 / 20 Passed

Description

92%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong, specific description that clearly states both what it does and when to invoke it, with concrete actions and a distinct trigger niche. The only gap is slightly thinner coverage of natural synonyms and extensions for trigger terms.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — 'Runs Stryker on the diff, triages surviving mutants, and posts findings as a PR comment with inline annotations on changed lines' — covering the niche comprehensively rather than vaguely.	5 / 5
Completeness	Explicit 'Use when reviewing a PR's test quality via mutation testing' answers when, and the action list clearly answers what, both with concrete trigger phrases.	5 / 5
Trigger Term Quality	Includes natural terms a user would say ('reviewing a PR's test quality', 'mutation testing', 'Stryker') but omits common synonyms like 'test effectiveness' and has no file extensions, leaving a few natural terms missing.	4 / 5
Distinctiveness Conflict Risk	Occupies a clear niche (mutation testing on a PR diff with posted review annotations) with distinct triggers and minimal overlap risk against other skills.	5 / 5
	Total	19 / 20 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: drufball/skylark
Path: plugins/skylark-builder/skills/mutation-review/SKILL.md
Commit: b5a3eaf

Reviewed: 6 days ago

Table of Contents

Discovery Implementation Validation

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