| name | api-development |
| model | reasoning |
| description | Meta-skill that orchestrates the full API development lifecycle — from design through documentation — by coordinating specialized skills, agents, and commands into a seamless build workflow. |
API Development
Orchestrate the full API development lifecycle by coordinating design, implementation, testing, and documentation into a single workflow.
When to Use This Skill
- Building a new API from scratch
- Adding endpoints to an existing API
- Redesigning or refactoring an API
- Planning API versioning and migration
- Running a complete API development cycle (design → build → test → document → deploy)
Orchestration Flow
Follow these steps in order. Each step routes to the appropriate skill or tool.
1. Design the API
Load the api-design skill to establish resource models, URL structure, HTTP method semantics, error formats, and pagination strategy.
Deliverables: Resource list, endpoint map, request/response schemas, error format
2. Generate OpenAPI Spec
Produce a machine-readable OpenAPI 3.x specification from the design. Use the OpenAPI template in api-design/assets/openapi-template.yaml as a starting point.
Deliverables: openapi.yaml with all endpoints, schemas, auth schemes, and examples
3. Scaffold Endpoints
Generate route files, request/response types, and validation schemas for each endpoint. Group routes by resource.
Deliverables: Route files, type definitions, validation schemas per resource
4. Implement Business Logic
Write service-layer logic with input validation, authorization checks, database queries, and proper error propagation. Keep controllers thin — business logic lives in the service layer.
Deliverables: Service modules, repository layer, middleware (auth, rate limiting, CORS)
5. Test
Write tests at three levels:
- Unit tests — service logic, validation, error handling
- Integration tests — endpoint behavior with real DB
- Contract tests — response shapes match OpenAPI spec
Deliverables: Test suite with coverage for happy paths, error cases, edge cases, and auth
6. Document
Generate human-readable API documentation with usage examples and SDK snippets. Ensure every endpoint has description, parameters, request/response examples, and error codes.
Deliverables: API docs, changelog, authentication guide
7. Version and Deploy
Apply a versioning strategy, tag the release, update changelogs, and deploy through the pipeline. Follow the api-versioning skill for deprecation and migration guidance.
Deliverables: Version tag, changelog entry, deployment confirmation
API Design Decision Table
Choose the right paradigm for your use case.
| Criteria | REST | GraphQL | gRPC |
|---|
| Best for | CRUD-heavy public APIs | Complex relational data, client-driven queries | Internal microservices, high-throughput |
| Data fetching | Fixed response shape per endpoint | Client specifies exact fields | Strongly typed protobuf messages |
| Over/under-fetching | Common problem | Solved by design | Minimal — schema is explicit |
| Caching | Native HTTP caching (ETags, Cache-Control) | Requires custom caching | No built-in HTTP caching |
| Real-time | Polling or WebSockets | Subscriptions (built-in) | Bidirectional streaming |
| Tooling | Mature — OpenAPI, Postman, curl | Growing — Apollo, Relay, GraphiQL | Mature — protoc, grpcurl, Buf |
| Learning curve | Low | Medium | Medium-High |
| Versioning | URL or header versioning | Schema evolution with @deprecated | Package versioning in .proto |
Rule of thumb: Default to REST for public APIs. Use GraphQL when clients need flexible queries across related data. Use gRPC for internal service-to-service communication.
API Checklist
Run through this checklist before marking any API work as complete.
Authentication & Authorization
Rate Limiting
Pagination
Filtering & Sorting
Error Handling
Versioning
CORS
Documentation
Security
Monitoring
Skill Routing Table
| Need | Skill | Purpose |
|---|
| API design principles | api-design | Resource modeling, HTTP semantics, pagination, error formats |
| Versioning strategy | api-versioning | Version lifecycle, deprecation, migration patterns |
| Authentication | auth-patterns | JWT, OAuth2, sessions, RBAC, MFA |
| Error handling | error-handling | Error types, retry patterns, circuit breakers, HTTP errors |
| Rate limiting | rate-limiting | Algorithms, HTTP headers, tiered limits, distributed limiting |
| Caching | caching | Cache strategies, HTTP caching, invalidation, Redis patterns |
| Database migrations | database-migrations | Schema evolution, zero-downtime patterns, rollback strategies |
NEVER Do
- NEVER skip the design phase — jumping straight to code produces inconsistent APIs that are expensive to fix
- NEVER expose database schema directly — API resources are not database tables; design around consumer use cases
- NEVER ship without authentication — every production endpoint must have an auth strategy
- NEVER return inconsistent error formats — every error response must follow the same schema
- NEVER break a published API without a versioning plan — breaking changes require a new version, migration guide, and deprecation timeline
- NEVER deploy without tests and documentation — untested APIs ship bugs, undocumented APIs frustrate developers
