codebase-analysis

A codebase review that scans a project for large files, organizational problems, and recurring code patterns, then saves a report. It combines measurements with a closer reading of the code.

In plain words
What is it for?
Use it when joining an unfamiliar project, checking project health, or preparing for a refactor. It helps assess file size, folder structure, dependencies between parts, naming, error handling, and other coding patterns.
Why use it?
It helps when a project is difficult to navigate or may need restructuring, by showing which problems are worth addressing first.

Skill for Claude CodeCodex

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/bytemines/sherpai/codebase-analysis
Any agent
npx skills add bytemines/sherpai --skill codebase-analysis
Clone the repo
git clone --depth 1 https://github.com/bytemines/sherpai

Made for: Claude Code, Codex.

Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,165 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00048 $0.01165
Opus 5 $0.00024 $0.00583
Sonnet 5 $0.00010 $0.00233
Haiku 4.5 $0.00005 $0.00117

Measured 2d ago against content hash 73d20b262dcc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codebase-analysis 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 2d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (analyzer.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.

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.

skills/codebase-analysis/SKILL.md · 151 lines

How it starts

The opening of the file, as written. The whole thing — 151 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Codebase Analysis

Scan, score, and analyze a codebase across three lenses in parallel. Python script does fast deterministic scanning; three agents do deep reasoning concurrently. Produces a persistent report.

Core principle: Numbers first, judgment second. Script finds what's big/complex, agents read the actual code to decide what matters.


Agents

This skill orchestrates three agents that run in parallel (they are independent):

Agent File Job
file-size-analyzer agents/file-size-analyzer.md Read large files, assess KEEP/SPLIT/CONSIDER
scope-organizer agents/scope-organizer.md Map directory structure, check cohesion & coupling
pattern-detector agents/pattern-detector.md Grep for naming, errors, anti-patterns, good patterns

When to Use

  • Onboarding to a new/unfamiliar codebase
  • "This repo feels messy" — need concrete data
  • Pre-refactoring assessment
  • Periodic health checks
  • After rapid growth phases

Do NOT use for:

  • Single file reviews (just read the file)
  • Known bugs (use systematic-debugging)
  • Style-only issues (use a linter)

Step 1: Run the Scanner

Run analyzer.py from this skill's directory. It scans the filesystem, counts lines/keywords/imports, scores files, and groups by scope.

# ASCII overview for the user
python skills/codebase-analysis/analyzer.py --root . --ascii

# JSON data for agents
python skills/codebase-analysis/analyzer.py --root . > /tmp/codebase-scan.json

Flags: --threshold N (min lines, default 200), --scope path/ (focus areas)

Present the ASCII report to the user. Read the JSON output — this is the data you'll feed to agents.


Step 2: Spawn 3 Agents in Parallel

From the JSON scan results, prepare the data slices and launch all three agents simultaneously using the Agent tool. All three in a single message — do NOT wait between them.

Agent 1: file-size-analyzer

Input: Top 10 largest files (or all files in urgent/refactor categories) with their paths, line counts, scores, and language. Prompt template:

Analyze these files from a codebase scan. For each, read the file and assess KEEP/SPLIT/CONSIDER.

Project: {project_name} ({project_type})
Files:
{for each file: path, lines, score, language, category}

Follow your agent instructions for process and output format.

Read the full file on GitHub · 151 lines

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. 2d ago First seen · 151 lines · 48 tokens per session scan A 73d20b262dcc

Subscribe to this mod's changes

codebase-analysis is a skill published in the GitHub repository bytemines/sherpai (4 stars, last pushed 5mo ago), licensed MIT. It adds 48 tokens to every session and 1,165 once invoked, about $0.0002 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 2026-08-31.

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

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

babysit-pr

Babysit a GitHub pull request after creation by continuously polling review comments, CI checks/workflow runs, and mergeability state until the PR is merged/closed or user help is required. Diagnose failures, retry likely flaky failures up to 3 times, auto-fix/push branch-related issues when appropriate, and keep…

openai/codex · 114 tokens

imagegen

Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…

openai/codex · 113 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 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