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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.

68

Quality

86%

Does it follow best practices?

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SecuritybySnyk

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Overview
Quality
Evals
Security
Files

Quality

Content

76%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.

The body is highly actionable with executable examples across all major VTC patterns and a tight structure, but it lacks an explicit validation/retry loop for its batch CI-testing workflow and a couple of cross-catalog references are loosely signposted.

Suggestions

Add an explicit validate-fix-rerun loop (e.g., run varnishtest, on FAILED inspect the failing expect line with -vvv, fix VCL/VTC, re-run) so the CI-gate workflow has a clear checkpoint.

Clarify that references/stale-while-revalidate.md and references/stampede.md live in the sibling cache-coherence-patterns-reference catalog rather than this skill's own bundle, to avoid a dead local reference.

Drop or tighten the repeated 'Per Varnish docs' framing and the re-explained x-cache HIT/MISS/GRACE logic to shave a few tokens.

DimensionReasoningScore

Conciseness

Largely lean and code-driven with no beginner-concept padding, but recurring 'Per Varnish docs' framing and re-explained x-cache status logic are minor instances of over-explanation that could be trimmed.

4 / 5

Actionability

Provides fully executable, copy-paste-ready VTC/VCL blocks, concrete install and run commands, parallel-run flags, and a CI yaml that together cover the common authoring and testing cases.

5 / 5

Workflow Clarity

The author-to-CI sequence is clear via section ordering, but validation/feedback checkpoints are only implicit; for a batch/regression-testing skill the rubric caps workflow clarity at 3 without an explicit validate-fix-rerun loop.

3 / 5

Progressive Disclosure

Well-organized with clear section headers and one-level-deep external references, but no bundle exists to validate against and the in-body reference to references/stale-while-revalidate.md is ambiguous about which catalog owns that file.

4 / 5

Total

16

/

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.

The description is specific, complete, and well-targeted, naming concrete capabilities and an explicit use-when trigger for Varnish VTC testing. Its only weakness is missing a few natural synonyms and the .vtc extension in the trigger terms.

DimensionReasoningScore

Specificity

Lists multiple concrete capabilities—the VTC block format, grace/saint-mode behaviours, PURGE handler with ACL guards, and surrogate-key invalidation via xkey vmod—giving comprehensive coverage rather than just a few actions.

5 / 5

Completeness

Explicitly answers both 'what' (wraps varnishtest/VTC for testing VCL; covers named patterns) and 'when' ('Use when authoring or testing Varnish-based caching layers') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Strong natural keywords (varnishtest, VTC, VCL, PURGE, grace-mode, surrogate-key, 'authoring or testing Varnish-based caching layers') but omits common synonyms and file extensions like '.vtc' or 'Varnish caching'.

4 / 5

Distinctiveness Conflict Risk

Targets a clear niche—Varnish VTC testing of VCL—with tool-specific triggers, making overlap with other skills minimal.

5 / 5

Total

19

/

20

Passed

Validation

93%

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

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

referenced_paths_exist

Referenced path issues: 3 missing

Warning

Total

15

/

16

Passed

Reviewed

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