api-design-expert

Included with Lifetime

$97 forever

Expert in RESTful API design, OpenAPI/Swagger documentation, versioning, error handling, and API best practices for NestJS applications

Design

What this skill does


# API Design Expert Skill

Expert in RESTful API design, OpenAPI/Swagger documentation, versioning strategies, error handling, and API best practices for NestJS applications.

## When to Use

- Designing new API endpoints
- Creating RESTful APIs
- Writing OpenAPI/Swagger documentation
- Implementing API versioning
- Designing error responses
- Creating DTOs and validation
- Implementing pagination, filtering, sorting

## Project Context Discovery

Before providing guidance:

1. Check `.agents/memory/` for API patterns and architecture notes
2. Review existing controllers and DTOs
3. Check for OpenAPI/Swagger setup
4. Review versioning strategy

## Core Principles

### RESTful Design

```typescript
// Use nouns, plural, hierarchical
GET    /api/users
GET    /api/users/:id
POST   /api/users
PUT    /api/users/:id
DELETE /api/users/:id
GET    /api/users/:id/posts
```

### HTTP Status Codes

- `200 OK` / `201 Created` / `204 No Content`
- `400 Bad Request` / `401 Unauthorized` / `403 Forbidden`
- `404 Not Found` / `409 Conflict` / `500 Internal Server Error`

### Response Format

```typescript
// Single resource
{ "data": {...}, "meta": {...} }

// List with pagination
{ "data": [...], "pagination": { "page", "limit", "total" } }
```

### Error Format

```typescript
{
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Validation failed",
    "details": [...],
    "timestamp": "...",
    "path": "/api/users"
  }
}
```

## Best Practices

- Consistent naming conventions
- Validate all inputs with DTOs
- OpenAPI/Swagger documentation
- Authentication on all endpoints
- Pagination for lists
- Version APIs from the start

---

**For complete DTO examples, pagination/filtering/sorting patterns, versioning strategies, OpenAPI setup, CRUD controller patterns, nested resources, bulk operations, and anti-patterns, see:** `references/full-guide.md`

Files: 3

Size: 10.5 KB

Complexity: 29/100

Category: Design

Source: https://github.com/shipshitdev/library/tree/main/bundles/backend/skills/api-design-expert

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Local-only OSS contribution command center. Auto-refreshes the user's in-flight PR and issue state on invoke so conversations start with full context — no need to brief Claude on what's in flight. Helps the user find issues to contribute to on GitHub, builds per-repo dossiers of what each upstream expects (CLA, DCO, branch convention, AI policy, draft-first, review bots, issue templates), runs deterministic gates before any external action so AI-assisted contributions don't reach maintainers as slop. State is markdown-only: candidate files at ~/.contribute-system/candidates/, repo dossiers at ~/.contribute-system/research/, append-only event log at ~/.contribute-system/log.jsonl. No database, no cloud calls. Use when the user asks about their PRs / issues / contributions, wants to find new work to take on, claim an issue, build/refresh a repo's dossier, or draft a Design Issue or PR. Trigger with "/contribute", "what's my PR status", "find a contribution", "claim issue X", "draft a Design Issue for Y", "refresh dossier for Z".

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