Name: fastly-fiddle
Rating: 72.8 (1 reviews)
Author: fastly

fastly-fiddle

Use when testing VCL against real Fastly edge infrastructure, writing assertion-based Fiddle tests, producing shareable fiddle URLs for bug reproductions, running VCL integration tests in CI, linting VCL remotely via the Fiddle API, or working with clientFetch/events/originFetches test expressions.

Quality

90%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

88%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.

An action-dense, well-structured body with executable commands, explicit validation checkpoints, and clean progressive disclosure into real one-level-deep reference files. The raw-curl flow slightly duplicates the helper, and the referenced examples/robots.json payload is missing from the bundle.

Suggestions

Add the missing examples/robots.json file (or fix the citation to point at an existing example payload) so the documented 'scripts/run-fiddle.sh examples/robots.json' invocation works as written.

Consider trimming the raw-curl 'full round trip' section to a brief 'see also' or collapsing it behind api.md, since run-fiddle.sh already covers publish → execute → SSE → completion with a bounded --max-wait.

Dimension	Reasoning	Score
Conciseness	Dense and assumes Claude's intelligence with no padding about what VCL/Fastly is; every gotcha is non-obvious domain knowledge. The raw-curl flow partially duplicates the bundled helper, leaving minor instances that could be trimmed, so it sits just below the lean anchor-5.	4 / 5
Actionability	Fully executable guidance — 'scripts/run-fiddle.sh --lint-only fiddle.json', exact curl invocations with headers, a complete JSON payload, and jq pipes — copy-paste ready and covering the lint-only, full round trip, and warm re-execute cases.	5 / 5
Workflow Clarity	Clear two-rule sequencing ('deliverable first, then the cheapest check') with explicit validation checkpoints ('valid==true ⇒ it compiles', 'bail here if valid is false', 'Subscribe to the SSE stream IMMEDIATELY', '--max-time caps') and feedback loops (timeout → re-execute the same warm FID; lint failure → details on stderr).	5 / 5
Progressive Disclosure	Clear overview with well-signaled one-level-deep references (references table plus inline 'See [api.md]' links) and content appropriately split into api.md, spec-shape.md, test-dsl.md, and run-fiddle.sh. The cited examples/robots.json file does not exist in the bundle, a minor navigation gap that keeps it just below anchor-5.	4 / 5
	Total	18 / 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.

A concise, specific description that covers what and when clearly with strong natural trigger terms and a distinct niche. Minor room to surface file extensions or the fiddle.fastly.dev URL directly in the description for even fuller trigger coverage.

Dimension	Reasoning	Score
Specificity	Lists six distinct concrete actions ('testing VCL against real Fastly edge infrastructure', 'writing assertion-based Fiddle tests', 'producing shareable fiddle URLs for bug reproductions', 'running VCL integration tests in CI', 'linting VCL remotely via the Fiddle API', 'working with clientFetch/events/originFetches test expressions') — comprehensive coverage matching the anchor-5 example.	5 / 5
Completeness	Explicitly answers both 'what' (the six actions) and 'when' via the opening 'Use when testing VCL...' clause with concrete trigger phrases throughout, matching the anchor-5 example.	5 / 5
Trigger Term Quality	Strong natural-vocabulary coverage ('VCL', 'Fastly edge', 'Fiddle tests', 'fiddle URLs', 'Fiddle API', 'clientFetch/events/originFetches') that users would actually say, but the description omits file extensions and the fiddle.fastly.dev URL that appear only in the body, so it falls just below the comprehensive anchor-5.	4 / 5
Distinctiveness Conflict Risk	Highly specific niche (Fastly Fiddle / real-edge VCL) with distinct triggers and minimal overlap risk with other skills; matches the anchor-5 'clear niche' example.	5 / 5
	Total	19 / 20 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
relative_links	Relative link issues: 1 missing	Warning

	Total	15 / 16 Passed

Repository: fastly/fastly-agent-toolkit
Path: skills/fastly-fiddle/SKILL.md
Commit: 42a6070

Reviewed: 2 days ago

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