recon-port-scan

recon-port-scan is a skill for Claude Code, Codex from crazyMarky/pentest-skills. It costs 49 tokens per session (2,736 once invoked), scanned B, original, Apache-2.0.

A guide to checking computers and networks for open connection points, the services using them, and sometimes their software versions or operating systems.

In plain words
What is it for?
Use it with nmap, masscan, or rustscan to scan ports, identify running services and versions, and fingerprint operating systems. Only scan systems you have permission to test.
Why use it?
It helps reveal what network services are exposed on authorised target systems, which is useful during security assessments.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: reads .claude/ paths.

Good fit Use it with nmap, masscan, or rustscan to scan ports, identify running services and versions, and fingerprint operating systems. Only scan systems you have permission to test.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/crazymarky/pentest-skills/recon-port-scan
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 crazyMarky/pentest-skills --skill recon-port-scan
Clone the repo
git clone --depth 1 https://github.com/crazyMarky/pentest-skills

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 recon-port-scan

README.md
[![agentmods](https://agentmods.dev/badge/skills/crazymarky/pentest-skills/recon-port-scan/github.svg)](https://agentmods.dev/skills/crazymarky/pentest-skills/recon-port-scan)
Your own site
<a href="https://agentmods.dev/skills/crazymarky/pentest-skills/recon-port-scan"><img src="https://agentmods.dev/badge/skills/crazymarky/pentest-skills/recon-port-scan/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 recon-port-scan

Your own site · 80×15
<a href="https://agentmods.dev/skills/crazymarky/pentest-skills/recon-port-scan"><img src="https://agentmods.dev/badge/skills/crazymarky/pentest-skills/recon-port-scan.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 49 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,736 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin original 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 $0.00049 $0.02736
Opus 5 $0.00024 $0.01368
Sonnet 5 $0.00010 $0.00547
Haiku 4.5 $0.00005 $0.00274

Measured 12d ago against content hash 87329211c190, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade B, and why

recon-port-scan scanned grade B 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 12d ago.

The scan reads SKILL.md. This mod also ships 4 executable files (scripts/masscan_to_nmap.py, scripts/merge_scan_results.py, scripts/parse_nmap_xml.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Asks for rootmediumPrivilege escalation

A mod that escalates privileges can change anything on the machine, not only the project.

- **nmap** - `sudo apt install nmap` (Debian/Ubuntu) or `brew install nmap` (macOS)
recon-port-scan/SKILL.md · 415 lines

How it starts

The opening of the file, as written. The whole thing — 415 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Port Scanning / Reconnaissance

Authorization Warning

IMPORTANT: Port scanning without proper authorization is illegal. Always ensure you have:

  • Written permission from the target system owner
  • Defined scope of authorized testing
  • Legal compliance with local regulations

Prerequisites

Required tools that must be installed on your system:

  • nmap - sudo apt install nmap (Debian/Ubuntu) or brew install nmap (macOS)

Optional tools:

  • masscan - High-speed port scanner
  • rustscan - Modern fast scanner with nmap integration

Quick Start

Most commonly used commands for port scanning:

Fast Common Port Scan

nmap -T4 -F <target>

Quick scan of top 100 common ports.

Full Port Scan with Service Detection

nmap -sV -sC -p- <target>

Scan all 65535 ports with version detection and default scripts.

Stealth SYN Scan

sudo nmap -sS -T2 -p- <target>

Stealthy scan (requires root).

High-Speed Large Range Scan

masscan -p1-65535 <target/CIDR> --rate=10000

Fast scanning of large IP ranges.

Common Scenarios

Scenario 1: Quick Reconnaissance

When you need fast results on common ports:

nmap -T4 -F <target>

Parameters:

  • -T4 - Aggressive timing template (faster)
  • -F - Fast mode, scan top 100 ports
  • <target> - IP address, hostname, or CIDR range

Example:

nmap -T4 -F 192.168.1.100
nmap -T4 -F example.com
nmap -T4 -F 192.168.1.0/24

Scenario 2: Full Port Range Discovery

When you need to find all open ports (1-65535):

nmap -p- <target>

Parameters:

  • -p- - Scan all 65535 ports

Example:

nmap -p- 192.168.1.100

With version detection:

nmap -sV -p- <target>

Scenario 3: Service Version Detection

When you need to identify running service versions:

nmap -sV -sC <target>

Parameters:

  • -sV - Probe open ports for service/version info
  • -sC - Run default NSE scripts

Read the full file on GitHub · 415 lines

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. 12d ago First seen · 415 lines · 49 tokens per session scan B 87329211c190

Subscribe to this mod's changes

recon-port-scan is a skill published in the GitHub repository crazyMarky/pentest-skills (308 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 49 tokens to every session and 2,736 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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