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testland/cold-start-budget-reference

Pure-reference catalog of cold-start budgets across serverless runtimes. Covers AWS Lambda's three-phase cold start (Init: download+unzip+runtime-bootstrap; Init code: imports + module load; Invoke: handler execution), Cloudflare Workers' isolate model (sub-millisecond cold starts via V8 isolates per developers.cloudflare.com), Vercel Edge Runtime, Lambda SnapStart for JVM (snapshot-restore for Java), and provisioned-concurrency trade-offs. Includes per-runtime typical cold-start ranges and the testable behaviours each model creates. Use when designing latency budgets, choosing a runtime, or auditing cold-start variance in production.

73

Quality

92%

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SecuritybySnyk

Passed

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Overview
Quality
Evals
Security
Files

Quality

Content

80%

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

A strong, well-structured reference catalog with concrete, executable guidance and a clear measurement-and-reverify workflow. Its main weaknesses are length that could be trimmed (some tables restate earlier content) and progressive-disclosure signals pointing to companion skills that are not bundled here.

Suggestions

Trim redundant tables: the 'Anti-patterns' and 'Testable behaviours' tables overlap the per-runtime budget table and mitigations — merge or cross-reference instead of restating.

Move the worked example and per-runtime budget table into a separate reference file (e.g. references/cold-start-budgets.md) to realize the progressive-disclosure pattern the body implies and shorten SKILL.md.

Confirm whether the named companion skills (lambda-timeout-budget-reference, etc.) exist in the bundle; if not, mark them as external/optional rather than implied references.

DimensionReasoningScore

Conciseness

The body is information-dense and avoids explaining basics Claude already knows, but at ~200 lines it is long for a reference catalog; several tables (anti-patterns, testable behaviours) restate points already made in the per-runtime table and mitigations, so it could be tightened.

2 / 3

Actionability

Provides concrete, executable guidance: a runnable lazy-import Python code block, specific numeric budgets and thresholds (e.g. 'zipped artifact < 50MB', 'init phase < 500ms'), explicit CloudWatch metric names ('Init Duration'), and named hooks ('beforeCheckpoint' / 'afterRestore').

3 / 3

Workflow Clarity

The 'How to use' section is a clearly sequenced 6-step process and the worked example reinforces it; measurement is tied to an explicit verification loop ('Re-measure after each change and confirm the p99 tail moved'), and the testable-behaviours table gives validation assertions for risky/deploy changes.

3 / 3

Progressive Disclosure

Structure is well-organized with clear sections and a references block, but the skill is essentially a single monolithic SKILL.md with no actual bundle files despite naming several companion skills ('lambda-timeout-budget-reference', consumed-by list); the one-level-deep reference pattern is signalled but not realized on disk.

2 / 3

Total

10

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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 precise, third-person description that states concrete capabilities, gives an explicit 'Use when' trigger, and occupies a distinct niche. It is dense but every clause carries information, so it avoids fluff while remaining complete.

DimensionReasoningScore

Specificity

Lists multiple concrete capabilities: 'three-phase cold start', 'Cloudflare Workers' isolate model', 'Lambda SnapStart for JVM (snapshot-restore)', 'provisioned-concurrency trade-offs', and 'per-runtime typical cold-start ranges', each with specific mechanism detail rather than vague abstraction.

3 / 3

Completeness

Explicitly answers both halves: what it does ('Pure-reference catalog of cold-start budgets... Includes per-runtime typical cold-start ranges and the testable behaviours') and when to use it ('Use when designing latency budgets, choosing a runtime, or auditing cold-start variance in production').

3 / 3

Trigger Term Quality

Contains natural terms a user would actually say — 'latency budgets', 'choosing a runtime', 'auditing cold-start variance', 'cold start' — alongside concrete runtime names. Coverage is strong and matches the phrasing of real requests.

3 / 3

Distinctiveness Conflict Risk

The niche is narrow and clearly bounded — serverless cold-start budgets across named runtimes — with triggers unlikely to overlap with adjacent skills, and it even names a companion ('lambda-timeout-budget-reference') to disambiguate scope.

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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