fastapi-security-testing

fastapi-security-testing is a skill for Claude Code, Codex from xAmirHamza77/PenKit51. It costs 23 tokens per session (3,463 once invoked), scanned A, original, no licence file.

A security-testing guide for FastAPI applications, a Python framework for building web APIs.

In plain words
What is it for?
Use it to test ASGI handling, dependency injection, and common API vulnerabilities.
Why use it?
It helps check risks specific to the way FastAPI handles requests, injected dependencies, and API access.

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/xamirhamza77/penkit51/fastapi-security-testing
Any agent
npx skills add xAmirHamza77/PenKit51 --skill fastapi-security-testing
Clone the repo
git clone --depth 1 https://github.com/xAmirHamza77/PenKit51

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-security-testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/xamirhamza77/penkit51/fastapi-security-testing.svg)](https://agentmods.dev/skills/xamirhamza77/penkit51/fastapi-security-testing)
Your own site
<a href="https://agentmods.dev/skills/xamirhamza77/penkit51/fastapi-security-testing"><img src="https://agentmods.dev/badge/skills/xamirhamza77/penkit51/fastapi-security-testing.svg" alt="Measured on agentmods" height="20"></a>
Per session 23 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,463 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00023 $0.03463
Opus 5 $0.00012 $0.01732
Sonnet 5 $0.00005 $0.00693
Haiku 4.5 $0.00002 $0.00346

Measured 4d ago against content hash f1e2bcb406a0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fastapi-security-testing 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 4d 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/fastapi-security-testing/SKILL.md · 410 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 4d ago First seen · 410 lines · 23 tokens per session scan A f1e2bcb406a0

Subscribe to this mod's changes

fastapi-security-testing is a skill published in the GitHub repository xAmirHamza77/PenKit51 (2 stars, last pushed 2mo ago), with no licence file. It adds 23 tokens to every session and 3,463 once invoked, about $0.0001 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 2026-08-31.

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