mass-assignment-testing

mass-assignment-testing is a skill for Claude Code, Codex from xAmirHamza77/PenKit51. It costs 18 tokens per session (2,920 once invoked), scanned A, original, no licence file.

A security-testing guide for checking whether API parameters can fill fields that users should not control, such as administrator privileges.

In plain words
What is it for?
It is for reviewing APIs for mass-assignment vulnerabilities and checking whether user-supplied parameters can change protected data.
Why use it?
It helps find unauthorized field changes and privilege-escalation risks caused by accepting too many input fields.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit It is for reviewing APIs for mass-assignment vulnerabilities and checking whether user-supplied parameters can change protected data.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/xamirhamza77/penkit51/mass-assignment-testing
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 xAmirHamza77/PenKit51 --skill mass-assignment-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 mass-assignment-testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/xamirhamza77/penkit51/mass-assignment-testing.svg)](https://agentmods.dev/skills/xamirhamza77/penkit51/mass-assignment-testing)
Your own site
<a href="https://agentmods.dev/skills/xamirhamza77/penkit51/mass-assignment-testing"><img src="https://agentmods.dev/badge/skills/xamirhamza77/penkit51/mass-assignment-testing.svg" alt="Measured on agentmods" height="20"></a>
Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,920 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 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 5.1 $0.00018 $0.02920
Opus 5 $0.00009 $0.01460
Sonnet 5 $0.00004 $0.00584
Haiku 4.5 $0.00002 $0.00292

Measured 7d ago against content hash 35607272e3b7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

mass-assignment-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 7d 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/mass-assignment-testing/SKILL.md · 334 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. 7d ago First seen · 334 lines · 18 tokens per session scan A 35607272e3b7

Subscribe to this mod's changes

mass-assignment-testing is a skill published in the GitHub repository xAmirHamza77/PenKit51 (2 stars, last pushed 2mo ago), with no licence file. It adds 18 tokens to every session and 2,920 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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