addyosmani/agent-skills

api-and-interface-design

Guides stable API and interface design. Use when designing APIs, module boundaries, or any public interface. Use when creating REST or GraphQL endpoints, defining type contracts between modules, or establishing boundaries between frontend and backend.

29K installs 92K starsUpdated Aug 29, 2026License: MIT

Install

npx skills add addyosmani/agent-skills@api-and-interface-design

Runs in your terminal. Adds the skill globally for Claude Code, Cursor, Codex and others; add -g -y to skip prompts.

What it does

API and Interface Design Overview Design stable, well-documented interfaces that are hard to misuse. Good interfaces make the right thing easy and the wrong thing hard. This applies to REST APIs, GraphQL schemas, module boundaries, component props, and any surface where one piece of code talks to another. When to Use - Designing new API endpoints - Defining module boundaries or contracts between teams - Creating component prop interfaces - Establishing database schema that informs API shape - Changing existing public interfaces Core Principles Hyrum's Law With a sufficient number of users of…

Excerpt from the skill's own SKILL.md. Read the full file on GitHub before installing: skills run with your agent's permissions.

View source on GitHub

Before you install

Skills are plain text instructions the agent follows, sometimes with scripts. Check the source, prefer repositories with many installs and stars, and read any script it ships.

Categories

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