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testland/varnish-test-vtc-syntax

Wraps the varnishtest CLI + VTC (Varnish Test Case) syntax for testing VCL configurations. Covers the VTC test-file format (varnishtest scripts with server { ... } + client { ... } + varnish v1 -vcl+backend { ... } blocks), the grace-mode + saint-mode behaviours (stale-while-revalidate + stale-if-error equivalents in VCL), the PURGE method handler pattern (vcl_purge subroutine + ACL guards), and surrogate-key invalidation via xkey vmod. Use when authoring or testing Varnish-based caching layers.

77

Quality

97%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

Overview
Quality
Evals
Security
Files

Quality

Content

92%

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

A strong, executable, well-organized testing skill with concise writing and a clear run/parse/CI feedback loop. Its one weakness is monolithic inline detail that, per progressive-disclosure guidance, could be split into reference bundle files to keep SKILL.md an overview.

Suggestions

Move the detailed PURGE / grace-mode / surrogate-key worked examples into separate reference files under references/ (e.g. PURGE-PATTERNS.md, GRACE-MODE.md) and have SKILL.md summarize each in 1–2 lines with a clearly signaled link, keeping the main file a lean overview.

Add a one-line 'what good output looks like' checkpoint in the Running section tying exit code + the 'TEST ... passed' line together as an explicit validation step before CI promotion.

Reconcile the description's mention of 'saint-mode' with the body, which only demonstrates grace mode — either add a brief saint-mode note or drop it from the description to avoid an unstated capability.

DimensionReasoningScore

Conciseness

Lean, domain-specific writing with tight tables and code blocks; assumes Claude's competence and avoids explaining generic concepts like caching basics. Inline comments are minimal and load-bearing, not padding.

3 / 3

Actionability

Provides fully executable guidance: install commands, complete VTC/VCL examples, run flags ('varnishtest -v', '-j 4', '-vvv'), CI YAML, and concrete pass/fail parsing — all copy-paste ready.

3 / 3

Workflow Clarity

Clear run→parse→CI sequence with inherent feedback (exit code 0/non-zero, 'passed'/'FAILED' output showing the failing expect line) and a troubleshooting anti-patterns table; the testing use case carries its own validate-fix-retry loop.

3 / 3

Progressive Disclosure

Well-sectioned and navigable, but the file is monolithic: ~276 lines of dense VTC/VCL reference detail inline rather than a thinner overview pointing to one-level-deep bundle files, and the 'References' list points to external docs/named companion skills rather than navigable bundle files.

2 / 3

Total

11

/

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.

An excellent description: third-person, concrete, with an explicit 'Use when' trigger and a distinct, conflict-resistant niche. Every dimension lands at the top anchor.

DimensionReasoningScore

Specificity

Lists multiple concrete actions: 'testing VCL configurations', 'VTC test-file format (varnishtest scripts with server { ... } + client { ... } + varnish v1 -vcl+backend { ... } blocks)', 'PURGE method handler pattern (vcl_purge subroutine + ACL guards)', and 'surrogate-key invalidation via xkey vmod' — far beyond a vague single-action description.

3 / 3

Completeness

Clearly answers both what (wraps varnishtest + VTC syntax for the listed behaviours) and when via the explicit trigger 'Use when authoring or testing Varnish-based caching layers.'

3 / 3

Trigger Term Quality

Covers natural terms a user testing Varnish would say: 'varnishtest', 'VTC', 'VCL', 'PURGE', 'grace mode', 'saint mode', 'surrogate-key', 'xkey vmod', 'caching layers'.

3 / 3

Distinctiveness Conflict Risk

A sharply defined Varnish-specific testing niche with distinctive technical triggers (VTC, vcl_purge, xkey) unlikely to fire for unrelated 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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