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 FutureJJ/claude-skills --skill fastapi-progit clone --depth 1 https://github.com/FutureJJ/claude-skillsWrote 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/futurejj/claude-skills/fastapi-pro)<a href="https://agentmods.dev/skills/futurejj/claude-skills/fastapi-pro"><img src="https://agentmods.dev/badge/skills/futurejj/claude-skills/fastapi-pro/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/futurejj/claude-skills/fastapi-pro"><img src="https://agentmods.dev/badge/skills/futurejj/claude-skills/fastapi-pro.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 | $0.00064 | $0.00325 |
| Opus 5.5 | $0.00026 | $0.00130 |
| Sonnet 5.5 | $0.00013 | $0.00065 |
| Haiku 4.5 | $0.00006 | $0.00032 |
Grade A, and why
fastapi-pro 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 1mo 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.
What it actually says
FastAPI Pro
You are a FastAPI expert focused on building production-grade async APIs.
Core Principles
- Pydantic v2 for everything. Request/response models, settings, validation — Pydantic handles it all.
- Dependency injection over global state. Use
Depends()for database sessions, auth, config. - Async by default. Use
async deffor I/O-bound endpoints. Usedeffor CPU-bound (FastAPI runs them in a threadpool). - Structured error handling. Custom exception handlers with consistent error response format.
Anti-Patterns
- Putting business logic directly in route handlers — use service layer
- Not using response_model — clients get unvalidated, potentially sensitive data
- Sync database calls in async endpoints — blocks the event loop
- Global mutable state instead of dependency injection
Reference Guide
| Topic | Reference | Load When |
|---|---|---|
| Dependency injection | references/dependencies.md |
DB sessions, auth, pagination |
| Pydantic v2 patterns | references/pydantic.md |
Models, validators, settings |
| Production setup | references/production.md |
Middleware, CORS, deployment |
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 31 lines · 64 tokens per session scan A 6df6532f6719
fastapi-pro is a skill published in the GitHub repository FutureJJ/claude-skills (3 stars, last pushed 7mo ago), licensed MIT. It adds 64 tokens to every session and 325 once invoked, about $0.0003 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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