api-development
Scanned@wpank
npx machina-cli add skill @wpank/api-development --openclawAPI 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
- Authentication mechanism chosen (JWT, OAuth2, API key)
- Authorization rules enforced at every endpoint
- Tokens validated and scoped correctly
- Secrets stored securely (never in code or logs)
Rate Limiting
- Rate limits configured per endpoint or consumer tier
-
RateLimit-*headers included in responses -
429 Too Many Requestsreturned withRetry-Afterheader - Rate limit strategy documented for consumers
Pagination
- All collection endpoints paginated
- Pagination style chosen (cursor-based or offset-based)
-
page_sizebounded with a sensible maximum - Total count or
hasNextPageindicator included
Filtering & Sorting
- Filter parameters validated and sanitized
- Sort fields allow-listed (no arbitrary column sorting)
- Default sort order defined and documented
Error Handling
- Consistent error response schema across all endpoints
- Correct HTTP status codes (4xx for client, 5xx for server)
- Validation errors return field-level detail
- Internal errors never leak stack traces or sensitive data
Versioning
- Versioning strategy selected and applied uniformly
- Breaking vs non-breaking change policy documented
- Deprecation timeline communicated via
Sunsetheader
CORS
- Allowed origins configured (no wildcard
*in production with credentials) - Allowed methods and headers explicitly listed
- Preflight (
OPTIONS) requests handled correctly
Documentation
- OpenAPI / Swagger spec generated and up to date
- Every endpoint has description, parameters, and example responses
- Authentication requirements documented
- Error codes and meanings listed
- Changelog maintained for each version
Security
- Input validation on all fields
- SQL injection prevention
- HTTPS enforced
- Sensitive data never in URLs or logs
- CORS configured correctly
Monitoring
- Structured logging with request IDs
- Error tracking configured (Sentry, Datadog, etc.)
- Performance metrics collected (latency, error rate)
- Health check endpoint available (
/health) - Alerts configured for error rate spikes
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
Overview
api-development is a meta-skill that orchestrates the full API lifecycle—from design to documentation—by coordinating specialized skills, agents, and commands into a seamless build workflow. It guides teams from API design through OpenAPI generation, endpoint scaffolding, business-logic implementation, testing, documentation, and deployment for cohesive API projects.
How This Skill Works
It follows a fixed orchestration flow: design the API with the api-design skill to establish resources, URL structure, methods, errors, and pagination; generate an OpenAPI 3.x spec from that design using the provided template; scaffold routes, types, and validation; implement the business logic in a thin controller layer with a robust service layer; and then test (unit, integration, contract), document with usage examples, and apply versioning and deployment. Each step yields concrete deliverables (openapi.yaml, route files, tests, docs) and is routed to the appropriate skill or tool.
When to Use It
- 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)
Quick Start
- Step 1: Design the API with the api-design skill to establish resource models, URL structure, HTTP methods, error formats, and pagination strategy.
- Step 2: Generate the OpenAPI 3.x spec from the design using the template at api-design/assets/openapi-template.yaml.
- Step 3: Scaffold endpoints, implement the service layer, add tests, and generate documentation; then perform versioning and deployment.
Best Practices
- Start with API design to align on resources, URL structure, methods, errors, and pagination.
- Reuse the OpenAPI template and keep documentation in sync with design.
- Keep controllers thin; place business logic in the service layer.
- Write unit, integration, and contract tests with OpenAPI-aligned expectations.
- Plan versioning, changelogs, and deployment early, following api-versioning guidance.
Example Use Cases
- Designing a new REST API for a fintech platform from scratch
- Adding a new endpoint to an existing e-commerce API
- Refactoring an API to support a breaking change with a documented migration path
- Versioning an API and coordinating deployment across services
- Automating an end-to-end pipeline from design through deployment in a microservices project