api-designer

Design REST and GraphQL APIs and generate OpenAPI 3.1 specifications.

Updated Mar 17, 2026
One-click install
npx skills add https://github.com/Estom/aiflex --skill api-designer-estom
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: api-designer
Source: https://github.com/Estom/aiflex/tree/main/skills-repo/Jeffallan-skills/api-designer
Command: npx skills add https://github.com/Estom/aiflex --skill api-designer-estom

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Provides a structured, production-ready process for designing APIs so teams avoid inconsistent contracts, poor pagination, unclear error handling, and undocumented authentication flows that slow development and break clients.

Core Features & Use Cases

  • Resource modeling & endpoint design: identify resources, relationships, and CRUD operations with consistent URI patterns and HTTP semantics.
  • OpenAPI 3.1 specification output: produce complete, documentation-ready specs including components, examples, and security schemes for code generation.
  • Versioning, pagination, and error standards: recommend URI/header versioning strategies, cursor/keyset/offset pagination patterns, and RFC 7807-style error formats with an error code catalog.
  • GraphQL schema planning: translate domain models into GraphQL types and queries/mutations when appropriate.
  • Use Case: design a public user management API with JWT authentication, cursor pagination for feeds, and a clear deprecation strategy for future versions.

Quick Start

Create an OpenAPI 3.1 specification for a product catalog API that includes list and detail endpoints, JWT bearer authentication, cursor pagination on collections, and a documented error response catalog.

Frequently Asked Questions about api-designer

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I design a REST API with complete OpenAPI 3.1 specifications?

To design a REST API with OpenAPI 3.1, model resources and endpoints with consistent URI patterns and HTTP semantics, then generate machine-readable specs including schemas, security schemes, and examples for code generation.

What's the best way to standardize API error responses?

Standardize API error responses by applying RFC 7807-style error formats with a documented error code catalog, ensuring clients receive consistent, machine-readable error details across all backend services.

How do I implement cursor pagination for API collections?

Implement cursor pagination by applying keyset or cursor-based pagination patterns to API collections, replacing offset strategies to provide stable results during data shifts and improve feed performance.

Can I generate a GraphQL schema from my domain model?

Yes, you can generate a GraphQL schema by translating domain models into GraphQL types, queries, and mutations when appropriate, providing a structured alternative or complement to REST endpoints.

How do I handle API versioning and deprecation for public APIs?

Handle API versioning by applying URI or header-based versioning strategies and generating migration guidance with clear deprecation policies for future versions of developer-facing backend services.

Does this API design process support JWT authentication flows?

Yes, the API design process supports JWT authentication by defining security schemes in the OpenAPI output, allowing you to design public APIs with bearer authentication and documented security flows.