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testland/flake-pattern-reference

Reference catalog of flake patterns - async/timing, test ordering, shared parallel state, resource leaks, network, locator drift, environment variance, randomness - with detection heuristics and remediation per pattern. Use when triaging an unknown flake to identify the category before bisecting.

75

Quality

94%

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SecuritybySnyk

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Overview
Quality
Evals
Security
Files

Quality

Content

85%

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

A high-quality reference catalog: concrete, executable remediation per pattern and a useful triage decision tree, organized into clean sections with flat navigation. The only weakness is a modest amount of introductory prose that re-establishes context Claude already has.

Suggestions

Trim the terminology note and the Google-correlation paragraph in the intro; the catalog stands on its own without defending the term 'flaky test' or citing the ~4.2M-test correlation.

Consider moving the per-pattern signal/remediation tables into a references/ file if the catalog grows, keeping SKILL.md as the decision tree plus a one-line pointer per pattern.

DimensionReasoningScore

Conciseness

The eight pattern tables and remediation lists are dense and earn their tokens, but the opening terminology note (provenance of 'flaky test', ISTQB status) and the Google-correlation observation re-explain context Claude already knows and could be trimmed.

2 / 3

Actionability

Remediation is copy-paste-ready and specific throughout — 'await expect(loc).toBeVisible()', 'PG_SCHEMA=test_${WORKER}', 'sinon.useFakeTimers()', MSW/nock/WireMock, 'page.getByRole(...)', 'faker.seed(N)' — with concrete flags and commands, not pseudocode.

3 / 3

Workflow Clarity

Although framed as a reference rather than a workflow, the triage decision tree gives a clearly sequenced, branching procedure that narrows one axis at a time, and the task is not a destructive/batch operation requiring validate-fix-retry checkpoints.

3 / 3

Progressive Disclosure

No bundle files exist and none are needed; the body is organized into eight discrete, well-signaled pattern sections plus a decision tree and a flat References list, with only one-level-deep links to sibling skills and external posts and no nested reference chains.

3 / 3

Total

11

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12

Passed

Description

100%

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: concrete, third-person, with an explicit 'Use when' trigger and a well-scoped niche that distinguishes it from adjacent debugging skills. It cleanly answers what the catalog contains and when to reach for it.

DimensionReasoningScore

Specificity

Enumerates eight concrete pattern categories (async/timing, test ordering, shared parallel state, etc.) and commits to delivering 'detection heuristics and remediation per pattern', naming multiple specific deliverables rather than vague actions.

3 / 3

Completeness

Explicitly answers both halves: the 'what' is a reference catalog of eight patterns with heuristics and remediation, and the 'when' is the explicit 'Use when triaging an unknown flake to identify the category before bisecting.' trigger clause.

3 / 3

Trigger Term Quality

Uses practitioner-natural terms a user would say when hitting a flake — 'flake patterns', 'unknown flake', 'triaging', 'bisecting' — alongside the eight category labels that mirror how teams actually describe these failures.

3 / 3

Distinctiveness Conflict Risk

Occupies a clear narrow niche — flake-pattern identification during triage, explicitly positioned as the reference sibling to the 'flaky-test-quarantine' workflow — making it unlikely to fire for unrelated debugging skills.

3 / 3

Total

12

/

12

Passed

Validation

100%

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

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Reviewed

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