property-based-testing

Property-based testing with fast-check (TypeScript/JavaScript) and Hypothesis (Python). Generate test cases automatically, find edge cases, and test mathematical properties. Use when user mentions property-based testing, fast-check, Hypothesis, generating test data, QuickCheck-style testing, or finding edge cases automatically.

Quality

81%

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Quality

Content

71%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 highly actionable, well-organized reference with executable code throughout, but it is a verbose monolith: it re-explains familiar concepts and duplicates the property catalog across both languages, and nothing is progressively disclosed into separate files.

Suggestions

Move the duplicated per-language property catalog (roundtrip, idempotence, commutativity, associativity, identity, inverse) into separate fast-check and hypothesis reference files, keeping one canonical example inline.

Delete or sharply trim the "Core Expertise" section — Claude already knows what property-based testing, generators, and shrinking are.

Split the generator/strategy API listings into references/ files and link to them from a concise quick-start section in SKILL.md.

Dimension	Reasoning	Score
Conciseness	The "Core Expertise" section explains concepts Claude already knows (traditional vs property-based testing, generators, shrinking) and the same six property patterns are duplicated verbatim across TypeScript and Python, inflating an already ~810-line body.	3 / 5
Actionability	Extensive copy-paste-ready, executable code covering installation, generators, custom strategies, common properties, shrinking, configuration, preconditions, stateful testing, and real-world examples for both libraries.	5 / 5
Workflow Clarity	Content is organized as a clear progression (install → basics → generators → properties → pitfalls → CI/CD → troubleshooting) with no destructive or batch operations requiring validation checkpoints.	4 / 5
Progressive Disclosure	Section headers are well organized, but the entire reference (~810 lines including API/generator listings for two libraries) is inlined in SKILL.md with no bundle files; content that belongs in separate reference files is not split out.	3 / 5
	Total	15 / 20 Passed

Description

91%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 description that concisely states what the skill does and gives explicit, keyword-rich trigger guidance covering both supported libraries and a synonym. Minor overlap risk with general testing skills and slightly abstract action verbs keep it just below maximum on two dimensions.

Dimension	Reasoning	Score
Specificity	Names the domain and several concrete actions — "Generate test cases automatically, find edge cases, and test mathematical properties" — but the actions stay slightly abstract compared to the fully concrete 5 anchor.	4 / 5
Completeness	Explicitly answers both what ("Generate test cases automatically, find edge cases, and test mathematical properties") and when ("Use when user mentions..." with concrete trigger phrases).	5 / 5
Trigger Term Quality	Comprehensive natural-term coverage including the concept name, both library names, and a synonym: "property-based testing, fast-check, Hypothesis, generating test data, QuickCheck-style testing, or finding edge cases automatically".	5 / 5
Distinctiveness Conflict Risk	Property-based testing is a clear niche with distinct triggers (fast-check, Hypothesis, QuickCheck-style), but "finding edge cases automatically" and "generating test data" overlap slightly with general/mutation testing skills.	4 / 5
	Total	18 / 20 Passed

Validation

81%

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 — 13 / 16 Passed

Validation for skill structure

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (823 lines); consider splitting into references/ and linking	Warning
allowed_tools_field	'allowed-tools' contains unusual tool name(s)	Warning
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	13 / 16 Passed

Repository: foryourhealth111-pixel/Vibe-Skills
Path: bundled/skills/property-based-testing/SKILL.md
Commit: d5ae560

Reviewed: 1 day ago

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