Testing vs Design · both proven

receiving-code-review vs vercel-composition-patterns

Both skills were run through Claude twice: once on a fixed brief without the skill, once with it. The briefs differ because each is written for the job the skill claims to do, so compare each skill against its own baseline, then decide which difference matters for your work. They are in different categories, so this is a choice of job, not a head-to-head on the same job.

receiving-code-review

Use when receiving code review feedback, before implementing suggestions, especially if feedback seems unclear or technically questionable - requires technical rigor and verification, not performative agreement or blind implementation

Category: Testing
Source: obra/superpowers
License: MIT
Proof model: claude-opus-5-5
Brief: “I received this code review on my pull request that adds caching to our product API. Decide what to do with each comment and present your responses and planned changes as a single HTML page. 1. "Cache TTL of 24h is too long, prices change during the day." 2. "Use Redis instead of the in-memory Map so all 4 instances share the cache." 3. "Rename getProd to getProduct." 4. "You should rewrite this whole module in TypeScript." 5. "The cache key ignores the currency query param, so EUR users can get USD prices." 6. "Add a test."”
Skill commit: 2ce8aa1

Without the skillWith receiving-code-review

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Without, runWith receiving-code-review, run3 independent runs per side, none selected by hand.

Download the with-skill page

vercel-composition-patterns

React composition patterns that scale. Use when refactoring components with boolean prop proliferation, building flexible component libraries, or designing reusable APIs. Triggers on tasks involving compound components, render props, context providers, or component architecture. Includes React 19 API changes.

Category: Design
Source: vercel-labs/agent-skills
License: Not stated
Proof model: claude-opus-5-5
Brief: “Refactor this React Modal component. It currently takes fourteen props, including isConfirm, isDanger, showFooter, footerAlign, hideClose, title, subtitle, icon, primaryLabel, secondaryLabel, onPrimary, onSecondary, size and children, and a dozen screens pass different combinations of them. Present the refactor as a single HTML page with the new API, the implementation, three call sites rewritten before and after, and a short note on why the new shape scales.”
Skill commit: 063bee9

Without the skillWith vercel-composition-patterns

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Without, runWith vercel-composition-patterns, run3 independent runs per side, none selected by hand.

Download the with-skill page

We don’t pick a winner for you: the pages are the evidence. Both proofs can be repeated with the brief, model and commit shown above. See alternatives to receiving-code-review or alternatives to vercel-composition-patterns.