recon-and-methodology

recon-and-methodology is a skill for Claude Code, Codex from yaklang/hack-skills. It costs 37 tokens per session (3,284 once invoked), scanned C, original, MIT.

A structured guide for examining a new website or service before security testing. It covers finding related domains, checking the technology in use, and listing reachable endpoints.

In plain words
What is it for?
Use it to map assets, identify software and services, build an endpoint inventory, and plan security tests.
Why use it?
It replaces ad-hoc probing with a repeatable way to understand what is in scope and where weaknesses may be found.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to map assets, identify software and services, build an endpoint inventory, and plan security tests.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/yaklang/hack-skills/recon-and-methodology
About the project

HackSkills is an organized knowledge base of installable skills that gives AI agents practical security knowledge across areas such as web security, privilege escalation, reverse engineering, and digital forensics. It is intended for bug bounty work, penetration testing, CTF competitions, and authorized security research. The catalogue entries are the project's own master, category, and topic skills.

yaklang/hack-skills · 2,133 stars · on GitHub

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 yaklang/hack-skills --skill recon-and-methodology
Clone the repo
git clone --depth 1 https://github.com/yaklang/hack-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-and-methodology

README.md
[![agentmods](https://agentmods.dev/badge/skills/yaklang/hack-skills/recon-and-methodology/github.svg)](https://agentmods.dev/skills/yaklang/hack-skills/recon-and-methodology)
Your own site
<a href="https://agentmods.dev/skills/yaklang/hack-skills/recon-and-methodology"><img src="https://agentmods.dev/badge/skills/yaklang/hack-skills/recon-and-methodology/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-and-methodology

Your own site · 80×15
<a href="https://agentmods.dev/skills/yaklang/hack-skills/recon-and-methodology"><img src="https://agentmods.dev/badge/skills/yaklang/hack-skills/recon-and-methodology.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,284 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 2 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 9 Apr 2026
  • Snyk fail 9 Apr 2026
How audits are shown
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 $0.00037 $0.03284
Opus 5 $0.00018 $0.01642
Sonnet 5 $0.00007 $0.00657
Haiku 4.5 $0.00004 $0.00328

Measured 6d ago against content hash e2536d18ddb0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade C, and why

recon-and-methodology scanned grade C 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 6d 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.

Reaches for credential fileshighPrivilege escalation

SSH keys, cloud credentials, git-credentials, .npmrc, /etc/shadow: reading these is how a config file becomes a credential leak.

/.aws/credentials → AWS credentials

Makes network callslowCapability

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

curl -s "https://crt.sh/?q=%.target.com&output=json" | jq -r '.[].name_value' | sort -u
Origin

Copies of this mod

3 near-identical copies found in the catalogue:

skills/recon-and-methodology/SKILL.md · 390 lines

How it starts

The opening of the file, as written. The whole thing — 390 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SKILL: Recon and Methodology — Expert Bug Bounty Playbook

AI LOAD INSTRUCTION: Systematic recon and bug-finding methodology from top bug hunters. Covers subdomain enumeration, endpoint discovery, tech fingerprinting, and the hunter's mental model for finding bugs that others miss. Key insight: most high-severity bugs are found through systematic coverage, not just clever payloads.


1. RECON HIERARCHY

Target Selection
└── Scope Definition (in-scope assets)
    └── Asset Discovery (subdomains, IPs, domains)
        └── Tech Fingerprinting (what's running)
            └── Endpoint Discovery (attack surface)
                └── Vulnerability Testing (per vulnerability type)

2. SUBDOMAIN ENUMERATION (CRITICAL FIRST STEP)

Passive (no DNS queries to target)

# Subfinder (aggregates multiple sources):
subfinder -d target.com -o subdomains.txt

# Amass passive:
amass enum -passive -d target.com

# Certsh (certificate transparency):
curl -s "https://crt.sh/?q=%.target.com&output=json" | jq -r '.[].name_value' | sort -u

# SecurityTrails API, Shodan:
# Web: https://securitytrails.com/list/apex_domain/target.com

Active (DNS brute force + resolution)

# Massdns + wordlist:
massdns -r /path/to/resolvers.txt -t A -o S -w output.txt \
  <(cat wordlist.txt | sed 's/$/.target.com/')

# ffuf for subdomain brute:
ffuf -w subdomains-wordlist.txt -u https://FUZZ.target.com \
  -mc 200,301,302,403 -H "Host: FUZZ.target.com"

# DNSx for bulk resolution:
cat subdomains.txt | dnsx -a -resp -o resolved.txt

# Recommended wordlist: SecLists/Discovery/DNS/

Virtual Host Discovery

# ffuf vhost mode:
ffuf -w wordlist.txt -u https://target.com \
  -H "Host: FUZZ.target.com" -mc 200,301,403

# gobuster vhost:
gobuster vhost -u https://target.com -w wordlist.txt

3. SERVICE AND PORT DISCOVERY

# Fast port scan (common ports):
nmap -T4 -F target.com -oN ports.txt

# Comprehensive scan on resolved subdomains:
cat resolved_ips.txt | nmap -iL - --open -p 80,443,8080,8443,8888,3000,5000 -oG scan.txt

# httpx for HTTP probing:
cat subdomains.txt | httpx -title -tech-detect -status-code -o live_hosts.txt

# masscan for speed on large IP ranges:
masscan -p 80,443,8080,8443 10.0.0.0/8 --rate=1000

Read the full file on GitHub · 390 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. 6d ago First seen · 390 lines · 37 tokens per session scan C e2536d18ddb0

Subscribe to this mod's changes

recon-and-methodology is a skill published in the GitHub repository yaklang/hack-skills (2,133 stars, last pushed 2mo ago), licensed MIT. It adds 37 tokens to every session and 3,284 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it C with 2 findings (reaches for credential files, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

local-ai-agents

Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…

microsoft/ai-agents-for-beginners · 200 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens

insight-error-page

Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…

vercel/next.js · 83 tokens

next-cache-components-optimizer

Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…

vercel/next.js · 170 tokens

next-partial-prefetching-adoption

Turn on Partial Prefetching in a Next.js app and work through the insights it surfaces. Use when the user wants to enable or adopt Partial Prefetching, flip the partialPrefetching flag, opt routes in with export const prefetch = 'partial', audit Link prefetch={true} behavior, preserve existing prefetched UI with…

vercel/next.js · 103 tokens