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.
npx skills add joaoguirunas/team-os --skill dev-api-designgit clone --depth 1 https://github.com/joaoguirunas/team-osWrote 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.
[](https://agentmods.dev/skills/joaoguirunas/team-os/dev-api-design)<a href="https://agentmods.dev/skills/joaoguirunas/team-os/dev-api-design"><img src="https://agentmods.dev/badge/skills/joaoguirunas/team-os/dev-api-design/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.
<a href="https://agentmods.dev/skills/joaoguirunas/team-os/dev-api-design"><img src="https://agentmods.dev/badge/skills/joaoguirunas/team-os/dev-api-design.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00027 | $0.01105 |
| Opus 5.5 | $0.00011 | $0.00442 |
| Sonnet 5.5 | $0.00005 | $0.00221 |
| Haiku 4.5 | $0.00003 | $0.00111 |
Grade A, and why
dev-api-design 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 27d 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.
How it starts
The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.
API Design — Software Complexo
REST — Nomenclatura
GET /users → listar
GET /users/:id → buscar por ID
POST /users → criar
PUT /users/:id → substituir completo
PATCH /users/:id → atualizar parcial
DELETE /users/:id → remover
# Ações não-CRUD (POST + verbo explícito)
POST /users/:id/deactivate
POST /auth/refresh
POST /payments/:id/refund
Regras: plural sempre (/users), nunca verbos em recursos, máx 2 níveis de aninhamento.
Responses
Sucesso
{
"data": { "id": "usr_123", "email": "[email protected]" },
"meta": { "requestId": "req_abc" }
}
Lista paginada
{
"data": [...],
"pagination": { "page": 1, "perPage": 20, "total": 150, "hasNext": true }
}
Erro — padrão obrigatório
{
"error": {
"code": "VALIDATION_ERROR",
"message": "Invalid request data",
"details": [{ "field": "email", "message": "Must be a valid email" }],
"requestId": "req_abc"
}
}
requestId obrigatório em todas as respostas — sucesso e erro. Gerado no middleware de entrada e propagado pelo sistema. Usar o mesmo requestId nos logs (ver dev-security-patterns) para rastrear requests end-to-end.
Nunca expor: stack traces, mensagens de banco, lógica interna.
HTTP Status + Códigos de Erro
| HTTP | Code | Quando |
|---|---|---|
| 200 | — | GET, PATCH, PUT ok |
| 201 | — | POST criou recurso |
| 204 | — | DELETE ou ação sem body |
| 400 | VALIDATION_ERROR |
Input inválido |
| 401 | UNAUTHORIZED |
Não autenticado |
| 403 | FORBIDDEN |
Sem permissão |
| 404 | NOT_FOUND |
Não existe |
| 409 | CONFLICT |
Estado conflitante |
| 429 | RATE_LIMITED |
Rate limit |
| 500 | INTERNAL_ERROR |
Erro interno |
requestId — Geração e Propagação
// Middleware de entrada — gerar requestId único
app.use((req, res, next) => {
req.requestId = req.headers['x-request-id'] as string
?? `req_${crypto.randomUUID().replace(/-/g, '').slice(0, 12)}`
res.setHeader('x-request-id', req.requestId)
next()
})
// Passar requestId para logs e serviços downstream
logger.info('Request received', { requestId: req.requestId, path: req.path })
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.
- 27d ago Changed 9fc22c70f577
- 1mo ago First seen · 144 lines · 27 tokens per session scan A 5f41f72a6684
dev-api-design is a skill published in the GitHub repository joaoguirunas/team-os (5 stars, last pushed 3d ago), licensed MIT. It adds 27 tokens to every session and 1,105 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-31.
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