prompt-injection-test

prompt-injection-test is a skill for Claude Code from jassics/awesome-claude-security. It costs 57 tokens per session (561 once invoked), scanned B, original, GPL-3.0.

A structured test for prompt injection, where untrusted instructions try to change what an AI chatbot, copilot, RAG app, or agent does.

In plain words
What is it for?
It is for authorized security testing of LLM features using direct and indirect attack payloads.
Why use it?
It shows whether user input or retrieved content can override the system's intended rules and records ways to reduce that risk.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the llm-security plugin — 3 skills, 1 agent shipped together

Good fit It is for authorized security testing of LLM features using direct and indirect attack payloads.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jassics/awesome-claude-security/prompt-injection-test
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 jassics/awesome-claude-security --skill prompt-injection-test
Clone the repo
git clone --depth 1 https://github.com/jassics/awesome-claude-security

Made for: Claude Code.

Or install llm-security, the plugin that ships this one along with the rest of its 3 skills, 1 agent.

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 prompt-injection-test

README.md
[![agentmods](https://agentmods.dev/badge/skills/jassics/awesome-claude-security/prompt-injection-test/github.svg)](https://agentmods.dev/skills/jassics/awesome-claude-security/prompt-injection-test)
Your own site
<a href="https://agentmods.dev/skills/jassics/awesome-claude-security/prompt-injection-test"><img src="https://agentmods.dev/badge/skills/jassics/awesome-claude-security/prompt-injection-test/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.

agentmods 80×15 button for prompt-injection-test

Your own site · 80×15
<a href="https://agentmods.dev/skills/jassics/awesome-claude-security/prompt-injection-test"><img src="https://agentmods.dev/badge/skills/jassics/awesome-claude-security/prompt-injection-test.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 561 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 2 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 $0.00057 $0.00561
Opus 5 $0.00028 $0.00280
Sonnet 5 $0.00011 $0.00112
Haiku 4.5 $0.00006 $0.00056

Measured 7d ago against content hash dd1cfd3cebd6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade B, and why

prompt-injection-test scanned grade B with 2 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.

Instruction-override phrasingmediumPrompt injection

Text telling the model to disregard its earlier instructions or safety rules is the shape of a prompt injection, whoever wrote it.

- Instruction override ("ignore previous instructions and …").

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Asks the agent to reveal its instructionslowSystem prompt leakage

Directions to print, repeat or translate the system prompt extract configuration the operator did not intend to expose.

- System-prompt extraction ("repeat the text above / your instructions").

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

plugins/llm-security/skills/prompt-injection-test/SKILL.md · 60 lines

The source is not reproduced here

Licensed GPL-3.0

The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

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 · 60 lines · 57 tokens per session scan B dd1cfd3cebd6

Subscribe to this mod's changes

prompt-injection-test is a skill published in the GitHub repository jassics/awesome-claude-security (6 stars, last pushed 1mo ago), licensed GPL-3.0. It adds 57 tokens to every session and 561 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it B with 2 findings (instruction-override phrasing, asks the agent to reveal its instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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