blackbox-bypasser

blackbox-bypasser is an agent for Claude Code from yanglittlecat/blackbox-pentest. It costs 120 tokens per session (1,806 once invoked), scanned A, original, no licence file.

A specialized sub-agent for authorized black-box penetration testing that investigates inputs blocked by a web application firewall, keyword filter, or input validation. It tries groups of bypass approaches and records reproducible evidence when they work.

In plain words
What is it for?
It is for testing filtered suspected vulnerabilities during an authorized pentest, using a URL, parameter, vulnerability type, and observed protection behavior.
Why use it?
It helps determine whether a blocked security test is genuinely prevented or only stopped by a bypassable filter. If no bypass works, it expands the evidence that the protection held.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md).

Good fit It is for testing filtered suspected vulnerabilities during an authorized pentest, using a URL, parameter, vulnerability type, and observed protection behavior.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/yanglittlecat/blackbox-pentest/blackbox-bypasser
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.

Clone the repo
git clone --depth 1 https://github.com/yanglittlecat/blackbox-pentest

Made for: Claude Code.

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 blackbox-bypasser

README.md
[![agentmods](https://agentmods.dev/badge/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser/github.svg)](https://agentmods.dev/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser)
Your own site
<a href="https://agentmods.dev/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser"><img src="https://agentmods.dev/badge/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser/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 blackbox-bypasser

Your own site · 80×15
<a href="https://agentmods.dev/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser"><img src="https://agentmods.dev/badge/agents/yanglittlecat/blackbox-pentest/blackbox-bypasser.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 120 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,806 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 $0.00120 $0.01806
Opus 5 $0.00060 $0.00903
Sonnet 5 $0.00024 $0.00361
Haiku 4.5 $0.00012 $0.00181

Measured 11d ago against content hash 2174e9637c0b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

blackbox-bypasser 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 11d 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.

agents/blackbox-bypasser.md · 67 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 11d ago First seen · 67 lines · 120 tokens per session scan A 2174e9637c0b

Subscribe to this mod's changes

blackbox-bypasser is an agent published in the GitHub repository yanglittlecat/blackbox-pentest (13 stars, last pushed 13d ago), with no licence file. It adds 120 tokens to every session and 1,806 once invoked, about $0.0006 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 2026-08-30.