# Javimontano Jm Adk Alfa REST API Development > REST API Development - Skill: `tomevault-io/javimontano-jm-adk-alfa-rest-api-development` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/javimontano-jm-adk-alfa-rest-api-development` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/javimontano-jm-adk-alfa-rest-api-development/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Integrations & APIs - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/javimontano-jm-adk-alfa-rest-api-development --- # REST API Development > "An API is a contract — break it, and you break trust." — Unknown ## TL;DR Guides RESTful API development on Cloud Functions using Express — route design, middleware chains, input validation, error handling, authentication, and API documentation. Use when building backend APIs for web or mobile clients on Firebase infrastructure. [EXPLICIT] ## Procedure ### Step 1: Discover - Identify API consumers (web app, mobile app, third-party integrations) - Map required endpoints from frontend data needs - Check existing API patterns or conventions in the codebase - Review authentication and authorization requirements per endpoint ### Step 2: Analyze - Design resource-oriented URLs: `/api/v1/users/:userId/orders` - Plan HTTP methods correctly: GET (read), POST (create), PUT/PATCH (update), DELETE - Define request/response schemas with consistent envelope format - Evaluate middleware needs: auth, validation, rate limiting, CORS, logging ### Step 3: Execute - Set up Express app wrapped in `onRequest` Cloud Function - Implement middleware chain: CORS → auth → validation → handler - Add input validation with Joi, Zod, or express-validator - Build consistent error responses: `{ error: { code, message, details } }` - Implement pagination: `{ data: [...], pagination: { total, page, limit, hasNext } }` - Add API versioning via URL prefix (`/api/v1/`) - Document endpoints with OpenAPI/Swagger specification ### Step 4: Validate - Test all endpoints with valid and invalid inputs - Verify auth middleware blocks unauthorized requests - Confirm error responses follow consistent format - Check API documentation matches actual behavior ## Quality Criteria - [ ] RESTful URL design with proper HTTP method usage - [ ] Input validation on all endpoints before business logic - [ ] Consistent error response format across all endpoints - [ ] Authentication enforced on protected endpoints - [ ] Evidence tags applied to all claims ## Anti-Patterns - Using POST for everything instead of appropriate HTTP methods - Returning 200 status code for errors (use proper 4xx/5xx codes) - Exposing internal error details (stack traces) in production responses ## Related Skills - `cloud-functions` — Express APIs run on Cloud Functions - `webhook-handling` — incoming webhooks are a specialized API pattern ## Usage Example invocations: - "/rest-api-development" — Run the full rest api development workflow - "rest api development on this project" — Apply to current context ## Assumptions & Limits - Assumes access to project artifacts (code, docs, configs) [EXPLICIT] - Requires English-language output unless otherwise specified [EXPLICIT] - Does not replace domain expert judgment for final decisions [EXPLICIT] ## Edge Cases | Scenario | Handling | |----------|----------| | Empty or minimal input | Request clarification before proceeding | | Conflicting requirements | Flag conflicts explicitly, propose resolution | | Out-of-scope request | Redirect to appropriate skill or escalate | --- > Source: [JaviMontano/jm-adk-alfa](https://github.com/JaviMontano/jm-adk-alfa) — distributed by [TomeVault](https://tomevault.io).