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testland/experiment-sdk-testing

Umbrella for experimentation-SDK test harnesses: the shared offline-datafile / hermetic-init pattern (commit a point-in-time flag/experiment config fixture, initialize the SDK with no network, pin arms per test, assert assignment integrity), with per-vendor references for Statsig (localMode + overrideGate), Optimizely (datafile + forced decisions), Split.io / Harness FME (localhost mode + features map or YAML fixture), Amplitude Experiment (local evaluation + bootstrap), and VWO (settings file + deterministic bucketing). Use when writing tests for application code instrumented with any of these five experimentation SDKs; for experiment DESIGN gates use ab-test-validity-checklist, and to read results use experiment-results-interpreter.

76

Quality

96%

Does it follow best practices?

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SecuritybySnyk

Passed

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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.

An exemplar content body: concise, executable, with a well-sequenced five-step workflow including integrity-test checkpoints, and a clean one-level-deep reference structure pointing to real per-vendor files. No substantive weaknesses found.

DimensionReasoningScore

Conciseness

Lean and efficient: it opens with a one-paragraph shared mechanism, a compact routing table, a numbered five-step pattern, one worked example, and tight anti-pattern/limitations tables, with no padding or explanation of concepts Claude already knows.

5 / 5

Actionability

Provides copy-paste-ready executable Python code with concrete imports and assertions, a precise routing table giving each vendor's exact offline switch and arm-pinning API, and specific anti-pattern fixes rather than abstract direction.

5 / 5

Workflow Clarity

The five-step hermetic-init pattern is explicitly sequenced with a validation-equivalent checkpoint (assert on values/keys not IDs) and two integrity tests (determinism and distribution) that act as feedback loops for catching fixture drift, plus teardown as an explicit final step.

5 / 5

Progressive Disclosure

SKILL.md is a clear overview with a routing table that links one level deep to seven real per-vendor reference files (all verified present in references/), with no nested or buried references and bulk vendor detail correctly split out of the main body.

5 / 5

Total

20

/

20

Passed

Description

90%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 highly specific, third-person description that clearly states both what the skill does and when to use it, with strong routing boundaries to neighboring skills. The only minor gap is the absence of common synonyms like 'A/B testing' or 'feature flags' that users may say.

Suggestions

Consider adding common synonyms such as 'A/B testing' or 'feature flag tests' to the trigger phrasing so users who don't say 'experimentation SDKs' still surface the skill.

DimensionReasoningScore

Specificity

Names the shared hermetic-init pattern and lists multiple concrete per-vendor actions (commit a config fixture, initialize the SDK with no network, pin arms per test, assert assignment integrity) with vendor-specific mechanics like 'localMode + overrideGate', 'datafile + forced decisions', and 'settings file + deterministic bucketing'.

5 / 5

Completeness

Explicitly answers 'what' (the shared offline-datafile / hermetic-init pattern with per-vendor references) and 'when' ('Use when writing tests for application code instrumented with any of these five experimentation SDKs'), with concrete trigger phrasing.

5 / 5

Trigger Term Quality

Includes natural user-facing phrases like 'writing tests for application code instrumented with ... experimentation SDKs' and names all five vendors, but lacks common synonyms like 'A/B testing' or 'feature flags' that a user might naturally say.

4 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (testing instrumentation code for five named experimentation SDKs) and explicitly routes adjacent tasks elsewhere (ab-test-validity-checklist for design gates, experiment-results-interpreter for reading results), minimizing conflict risk.

5 / 5

Total

19

/

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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