code-recon

code-recon is a skill for Claude Code, Codex from eugenepyvovarov/mcpbundler-agent-skills-marketplace. It costs 0 tokens per session (3,503 once invoked), scanned A, a copy of zz-code-recon, MIT.

A structured way to study an unfamiliar codebase from its overall design down to individual functions. It maps system parts, data movement, trust boundaries, and security-sensitive logic.

In plain words
What is it for?
Use it to prepare for security audits, code reviews, or work on an unfamiliar project. It helps identify architecture, modules, important functions, data flows, and places where trust changes.
Why use it?
Security reviews and code reviews are harder when the reviewer does not understand how the software fits together. This approach builds that understanding before detailed investigation.

Skill for Claude CodeCodex

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

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is ./scripts/recon.sh /path/to/project.

Good fit Use it to prepare for security audits, code reviews, or work on an unfamiliar project. It helps identify architecture, modules, important functions, data flows, and places where trust changes.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/eugenepyvovarov/mcpbundler-agent-skills-marketplace
agentmods
npx agentmods add skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon

Made for: Claude Code, Codex.

Its marketplace also offers this one on its own, as the plugin code-recon/plugin install code-recon after adding the marketplace above.

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 code-recon

README.md
[![agentmods](https://agentmods.dev/badge/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon/github.svg)](https://agentmods.dev/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon)
Your own site
<a href="https://agentmods.dev/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon"><img src="https://agentmods.dev/badge/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon/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 code-recon

Your own site · 80×15
<a href="https://agentmods.dev/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon"><img src="https://agentmods.dev/badge/skills/eugenepyvovarov/mcpbundler-agent-skills-marketplace/code-recon.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,503 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 91% copy Near-identical to another mod 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 $0.00000 $0.03503
Opus 5 $0.00000 $0.01751
Sonnet 5 $0.00000 $0.00701
Haiku 4.5 $0.00000 $0.00350

Measured 12d ago against content hash 5d4bd1aa630c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

code-recon 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 12d 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.

Origin

This is a copy

91% identical to zz-code-recon — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

code-recon/SKILL.md · 483 lines

How it starts

The opening of the file, as written. The whole thing — 483 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CodeRecon - Deep Architectural Context Building

Build comprehensive architectural understanding through ultra-granular code analysis. Designed for security auditors, code reviewers, and developers who need to rapidly understand unfamiliar codebases before diving deep.

Overview

CodeRecon is a systematic approach to codebase reconnaissance that builds layered understanding from high-level architecture down to implementation details. Inspired by Trail of Bits' audit-context-building methodology.

Why CodeRecon?

Before you can find vulnerabilities, you need to understand:

  • How the system is architected
  • Where data flows
  • What the trust boundaries are
  • Where security-critical logic lives

This skill provides a structured methodology for building that context efficiently.

The Recon Pyramid

                    ┌─────────────┐
                    │   DETAILS   │  ← Implementation specifics
                   ─┼─────────────┼─
                  / │  FUNCTIONS  │  ← Key function analysis
                 /  ─┼─────────────┼─
                /   │   MODULES   │  ← Component relationships
               /    ─┼─────────────┼─
              /     │ ARCHITECTURE│  ← System structure
             /      ─┼─────────────┼─
            /       │   OVERVIEW  │  ← High-level understanding
           ─────────┴─────────────┴─────────

Start broad, go deep systematically.

Phase 1: Overview Reconnaissance

1.1 Project Identification

Gather basic project information:

# Check for documentation
ls -la README* ARCHITECTURE* SECURITY* CHANGELOG* docs/

# Identify build system
ls package.json Cargo.toml go.mod pyproject.toml Makefile

# Check for tests
ls -la test* spec* *_test* __tests__/

# Identify CI/CD
ls -la .github/workflows/ .gitlab-ci.yml Jenkinsfile .circleci/

1.2 Technology Stack Detection

# Language distribution
find . -type f -name "*.py" | wc -l
find . -type f -name "*.js" -o -name "*.ts" | wc -l
find . -type f -name "*.go" | wc -l
find . -type f -name "*.rs" | wc -l
find . -type f -name "*.sol" | wc -l

# Framework indicators
grep -r "from flask" --include="*.py" | head -1
grep -r "from django" --include="*.py" | head -1
grep -r "express\|fastify" --include="*.js" | head -1
grep -r "anchor_lang" --include="*.rs" | head -1

Read the full file on GitHub · 483 lines

Files

What ships with it

5 files 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. 12d ago First seen · 483 lines · 0 tokens per session scan A 5d4bd1aa630c

Subscribe to this mod's changes

code-recon is a skill published in the GitHub repository eugenepyvovarov/mcpbundler-agent-skills-marketplace (12 stars, last pushed 6mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 3,503 tokens. A static security scan graded it A with 0 findings. It is 91% identical to zz-code-recon, differing in 5 lines, and is treated as a copy.

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