fastapi

fastapi is a skill for Claude Code, Codex from DongDuong2001/pudo-code-system. It costs 0 tokens per session (381 once invoked), scanned A, original, MIT.

A set of guidelines for building and reviewing FastAPI web APIs in Python. FastAPI is a Python framework for creating HTTP services.

In plain words
What is it for?
Planning and implementing FastAPI endpoints, Pydantic request and response schemas, database access, authentication, middleware, pagination, and consistent error responses.
Why use it?
It helps organize API routes, validate incoming data, manage dependencies, handle errors, and avoid blocking work in asynchronous endpoints.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/dongduong2001/pudo-code-system/fastapi
Any agent
npx skills add DongDuong2001/pudo-code-system --skill fastapi
Clone the repo
git clone --depth 1 https://github.com/DongDuong2001/pudo-code-system

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.

agentmods badge for fastapi

README.md
[![agentmods](https://agentmods.dev/badge/skills/dongduong2001/pudo-code-system/fastapi.svg)](https://agentmods.dev/skills/dongduong2001/pudo-code-system/fastapi)
Your own site
<a href="https://agentmods.dev/skills/dongduong2001/pudo-code-system/fastapi"><img src="https://agentmods.dev/badge/skills/dongduong2001/pudo-code-system/fastapi.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 381 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00381
Opus 5 $0.00000 $0.00191
Sonnet 5 $0.00000 $0.00076
Haiku 4.5 $0.00000 $0.00038

Measured 3d ago against content hash eaa201e2e899, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fastapi 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 3d 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.

skills/backend/fastapi/SKILL.md · 24 lines

What it actually says

Python FastAPI PUDO Checklist

1. PLAN (Architecture & Strategy)

  • API Design: Define RESTful endpoints, path parameters, and query parameters.
  • Data Validation: Plan Pydantic models for request (In) and response (Out) schemas.
  • Database & ORM: Select the async DB driver and ORM (e.g., SQLAlchemy 2.0 with async engine, SQLModel).
  • Authentication: Plan dependency injection for Auth (OAuth2, JWT tokens).

2. UNDERSTAND (Context & Auditing)

  • Dependencies: Review the existing dependency injection (Depends()) tree.
  • Sync vs Async: Audit for blocking I/O calls within async def endpoints. Ensure CPU-bound tasks use def or thread pools.
  • Middleware: Review CORS, rate limiting, and custom middleware configurations.

3. DEVELOP (Implementation)

  • Schemas: Implement strict Pydantic v2 models with Field validation constraints.
  • Endpoints: Create routers (APIRouter) to group related endpoints.
  • Dependency Injection: Use Depends() for database sessions, current user retrieval, and pagination parameters.
  • Error Handling: Implement custom Exception Handlers for consistent JSON error responses.

4. OPTIMIZE (Performance & Review)

  • Concurrency: Ensure database calls are utilizing await properly without deadlocks.
  • Serialization: Profile Pydantic serialization speeds; consider orjson if JSON parsing is a bottleneck.
  • Documentation: Enrich OpenAPI docs with endpoint descriptions, tags, and summary response models.
  • Security: Verify that sensitive models do not leak password hashes via response_model constraints.
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.

  1. 3d ago First seen · 24 lines · 0 tokens per session scan A eaa201e2e899

Subscribe to this mod's changes

fastapi is a skill published in the GitHub repository DongDuong2001/pudo-code-system (5 stars, last pushed 27d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 381 tokens. 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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