What is construtor-de-api?

A guide to designing and documenting REST and GraphQL APIs. An API is an agreed way for software systems to exchange data; the guide covers endpoints, versioning, authentication, errors, and OpenAPI documentation.

Use it to design endpoints, define GraphQL schemas, document services, add authentication and authorization, standardize errors, and plan API versioning.

It helps keep APIs predictable for the developers and applications that use them. It also reduces confusion around permissions, invalid requests, response codes, and future changes.

construtor-de-api — Skill for Claude Code and Codex by ricneves-ai

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add ricneves-ai/flowgrammers-skills --skill construtor-de-api

Clone the repo

git clone --depth 1 https://github.com/ricneves-ai/flowgrammers-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/ricneves-ai/flowgrammers-skills/construtor-de-api/github.svg)](https://agentmods.dev/skills/ricneves-ai/flowgrammers-skills/construtor-de-api)

Your own site

<a href="https://agentmods.dev/skills/ricneves-ai/flowgrammers-skills/construtor-de-api"><img src="https://agentmods.dev/badge/skills/ricneves-ai/flowgrammers-skills/construtor-de-api/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/ricneves-ai/flowgrammers-skills/construtor-de-api"><img src="https://agentmods.dev/badge/skills/ricneves-ai/flowgrammers-skills/construtor-de-api.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 876 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00046	$0.00876
Opus 5	$0.00023	$0.00438
Sonnet 5	$0.00009	$0.00175
Haiku 4.5	$0.00005	$0.00088

Measured 8d ago against content hash a895a5f03522, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

construtor-de-api scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

codigo-automacao/construtor-de-api/SKILL.md · 100 lines

How it starts

The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Especialista em Construção de APIs

Você é um engenheiro sênior especializado em design e implementação de APIs. Seu papel é criar APIs que sejam intuitivas, bem documentadas, seguras e performáticas.

Quando Usar Esta Skill

Projetar novos endpoints REST ou schema GraphQL
Documentar API existente com OpenAPI 3.0
Implementar autenticação e autorização
Criar estratégia de versionamento e deprecação
Otimizar performance de endpoints lentos

Princípios de Design REST

Nomenclatura de Endpoints

Recursos no plural: /users, /orders, /products
Verbos HTTP corretos: GET (ler), POST (criar), PUT (substituir), PATCH (atualizar), DELETE (remover)
Relações aninhadas: /users/{id}/orders (máximo 2 níveis)
Filtros como query params: /products?category=eletronicos&priceMax=500

Códigos HTTP Corretos

Situação	Código
Criação com sucesso	201 Created
Recurso não encontrado	404 Not Found
Dados inválidos	422 Unprocessable Entity
Não autorizado	401 Unauthorized
Sem permissão	403 Forbidden
Erro interno	500 Internal Server Error

Estrutura de Erro Padronizada (RFC 7807)

{
  "type": "https://api.exemplo.com/errors/validation-failed",
  "title": "Validation Failed",
  "status": 422,
  "detail": "O campo CPF é obrigatório",
  "instance": "/users/register"
}

Documentação OpenAPI 3.0

Toda API deve ter:

Info: título, versão, descrição
Servers: URLs por ambiente (dev, staging, prod)
Security schemes: Bearer JWT ou API Key
Paths: todos os endpoints com request/response examples
Components: schemas reutilizáveis, respostas de erro padrão

Integrações BR Comuns

Mercado Pago API: webhooks de pagamento PIX e cartão
ViaCEP: lookup de endereço por CEP
CNPJ.io: validação e consulta de CNPJ
BrasilAPI: CEP, CNPJ, bancos, feriados em uma API gratuita
Focus NFe / NF-e.io: emissão de nota fiscal

Exemplos de Prompts

Use api-builder para criar documentação OpenAPI 3.0 da minha API de [domínio].
Endpoints que preciso documentar: [lista].
Autenticação: [JWT/API Key/OAuth].
Crie spec completo com exemplos de request/response e todos os erros possíveis.

Read the full file on GitHub · 100 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago First seen · 100 lines · 46 tokens per session scan A a895a5f03522

Subscribe to this mod's changes

construtor-de-api is a skill published in the GitHub repository ricneves-ai/flowgrammers-skills (112 stars, last pushed 3mo ago), licensed MIT. It adds 46 tokens to every session and 876 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Backend and APIs Security api graphql openapi rest

api-design-patterns

Design robust APIs with RESTful patterns, GraphQL schemas, versioning strategies, and error handling conventions. Supports OpenAPI/Swagger documentation and SDK generation patterns. Triggers on API design, schema definition, endpoint architecture, or developer experience requests.

organvm-iv-taxis/a-i--skills · 54 tokens

api-designer

Designs production-grade APIs — REST, GraphQL, gRPC, and AsyncAPI patterns including pagination, versioning, error handling, rate limiting, and API governance. Use when the user asks to design APIs, create endpoints, build an API layer, write OpenAPI specs, or needs help with REST/GraphQL/gRPC service design.

buiphucminhtam/forgewright · 73 tokens

api-design

Design and implement RESTful APIs with proper routing, validation, error handling, and documentation. Use when building new API endpoints, designing API architecture, or improving existing APIs.

asgarovf/locusai · 37 tokens

api-design-first

Design-first API development skill. Generates OpenAPI 3.1 specifications, enforces REST design best practices, validates endpoints, handles versioning, pagination, error formatting, authentication patterns, rate limiting, and idempotency. Activates when users say "design an API", "create OpenAPI spec", "API endpoint"…

JPeetz/agent-skills · 117 tokens

lap

LAP CLI -- compile, search, and manage API specs for AI agents. Use when working with API specifications (OpenAPI, GraphQL, AsyncAPI, Protobuf, Postman), compiling specs to LAP format, searching the LAP registry, generating skills from API specs, or publishing APIs. Commands: init, compile, search, get, skill…

Lap-Platform/LAP · 89 tokens

lap