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testland/cache-coherence-patterns-reference

Pure-reference catalog of cache-coherence patterns across the request path. Defines the five-tier cache stack (browser → CDN → reverse-proxy → application → data store), the per-tier cache-writing patterns (cache-aside, write-through, write-back, write-around, refresh-ahead), and the canonical invalidation strategies (TTL-only, event-driven purge, surrogate keys, version-tagged URLs, soft purge), plus an anti-pattern table and a worked multi-tenant coherence-test example. Deep detail lives in references/: RFC 9111 Cache-Control / Vary / ETag directive tables, the cross-tier test surface, cache-stampede (thundering-herd) mitigations incl. the XFetch formula, and RFC 5861 stale-while-revalidate / stale-if-error semantics. Use for pattern selection, Cache-Control header design, coherence audits, stampede-refresh strategy, and SWR/SIE window design; use a cache-key-collision check when the question is whether two concrete requests collide on a key scheme.

80

Quality

100%

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SecuritybySnyk

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Overview
Quality
Evals
Security
Files

Quality

Content

100%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 well-structured pure-reference skill: dense tables, a clear 5-step decision workflow with a re-check feedback loop, a worked multi-tenant example with test assertions, and cleanly signaled one-level-deep companion references. It is concise, actionable for pattern selection, and well-organized for progressive disclosure.

DimensionReasoningScore

Conciseness

The body is lean and table-driven, assumes Claude's knowledge (no 'what is a cache' padding), and every section — five-tier stack, pattern tables, worked example — earns its tokens; the only prose is the justified worked example.

5 / 5

Actionability

Though code-free (an instruction/reference skill, explicitly not penalized), it gives concrete actionable guidance: named patterns with When/Trade-off columns, specific directives (`Cache-Control: private`, `Vary: Authorization`, content-hash ETag), and an Arrange/Act/Assert worked example that is directly applicable.

5 / 5

Workflow Clarity

The 5-step 'How to use' process is clearly sequenced with an explicit re-check-against-anti-patterns feedback loop and a checklist (anti-patterns table); the worked test adds Assert validation. It is not a destructive/batch operation, so the cap does not apply.

5 / 5

Progressive Disclosure

The body is a self-described 'decision surface' with a 'Deep references' section clearly signaling four one-level-deep companion files (all verified to exist, with no nested references inside them) and their contents, giving easy navigation.

5 / 5

Total

20

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20

Passed

Description

100%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 dense, third-person description that comprehensively enumerates concrete capabilities and reference contents while giving explicit, concrete trigger guidance for when to use the skill. It is information-rich rather than padded, with clear distinctiveness and a boundary pointer to a related collision-check skill.

DimensionReasoningScore

Specificity

The description lists many specific concrete actions and structures — the five-tier stack, five named cache-writing patterns, five named invalidation strategies, an anti-pattern table, and a worked example — with no coverage gaps, matching the 'comprehensive coverage' anchor.

5 / 5

Completeness

It explicitly answers 'what' (defines the stack, patterns, strategies, example; deep detail in references) and 'when' ('Use for pattern selection, Cache-Control header design, coherence audits, stampede-refresh strategy, and SWR/SIE window design…'), matching the clear-what-and-when-with-triggers anchor.

5 / 5

Trigger Term Quality

It covers the natural terms a user would say ('cache', 'CDN', 'Cache-Control', 'stale data', 'invalidation', 'Vary', 'ETag') plus synonyms ('cache stampede (thundering-herd)', 'SWR/SIE = stale-while-revalidate/stale-if-error'), meeting the comprehensive-synonyms anchor.

5 / 5

Distinctiveness Conflict Risk

It occupies a clear niche (cache-coherence pattern reference) with distinct triggers and even a boundary handoff to a separate cache-key-collision check, giving minimal conflict risk.

5 / 5

Total

20

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20

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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