api-21-mtls

api-21-mtls is a skill for Claude Code, Codex from vigilantshield/Claude-HunterKit. It costs 45 tokens per session (2,003 once invoked), scanned A, original, no licence file.

A security-testing skill for mutual TLS, a setup where both the client and server prove their identity with certificates.

In plain words
What is it for?
Use it to test certificate validation, client-certificate spoofing, mTLS downgrades, and certificate-pinning bypasses.
Why use it?
It helps test whether certificate checks, downgrade protections, and certificate pinning can be bypassed or spoofed.

Skill for Claude CodeCodex

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

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/vigilantshield/claude-hunterkit/api-21-mtls
Any agent
npx skills add vigilantshield/Claude-HunterKit --skill api-21-mtls
Clone the repo
git clone --depth 1 https://github.com/vigilantshield/Claude-HunterKit

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 api-21-mtls

README.md
[![agentmods](https://agentmods.dev/badge/skills/vigilantshield/claude-hunterkit/api-21-mtls.svg)](https://agentmods.dev/skills/vigilantshield/claude-hunterkit/api-21-mtls)
Your own site
<a href="https://agentmods.dev/skills/vigilantshield/claude-hunterkit/api-21-mtls"><img src="https://agentmods.dev/badge/skills/vigilantshield/claude-hunterkit/api-21-mtls.svg" alt="Measured on agentmods" height="20"></a>
Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,003 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. 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 5.1 $0.00045 $0.02003
Opus 5 $0.00023 $0.01001
Sonnet 5 $0.00009 $0.00401
Haiku 4.5 $0.00005 $0.00200

Measured 5d ago against content hash c2d51f46680a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

api-21-mtls scanned grade A with 1 finding 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 5d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- curl / httpx
skills/api/api-21-mtls/SKILL.md · 250 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

Files

What ships with it

1 file 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.

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. 5d ago First seen · 250 lines · 45 tokens per session scan A c2d51f46680a

Subscribe to this mod's changes

api-21-mtls is a skill published in the GitHub repository vigilantshield/Claude-HunterKit (5 stars, last pushed 1mo ago), with no licence file. It adds 45 tokens to every session and 2,003 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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