repo-onboarding

repo-onboarding is a skill for Claude Code, Codex from jnMetaCode/skillet. It costs 48 tokens per session (613 once invoked), scanned A, original, MIT.

A codebase onboarding skill for mapping an unfamiliar repository before changing it. A repository is a project's tracked files, and the skill examines how it runs, is tested, and is organized.

In plain words
What is it for?
Use it to inspect the README and project manifest, find entry points, run the tests, map key directories, sample coding conventions, and trace configuration and input/output paths.
Why use it?
It reduces guesses about where changes belong and exposes a failing test baseline before new work is blamed for existing problems.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions CLAUDE.md.

Good fit Use it to inspect the README and project manifest, find entry points, run the tests, map key directories, sample coding conventions, and trace configuration and input/output paths.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jnmetacode/skillet/repo-onboarding
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 jnMetaCode/skillet --skill repo-onboarding
Clone the repo
git clone --depth 1 https://github.com/jnMetaCode/skillet

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 repo-onboarding

README.md
[![agentmods](https://agentmods.dev/badge/skills/jnmetacode/skillet/repo-onboarding/github.svg)](https://agentmods.dev/skills/jnmetacode/skillet/repo-onboarding)
Your own site
<a href="https://agentmods.dev/skills/jnmetacode/skillet/repo-onboarding"><img src="https://agentmods.dev/badge/skills/jnmetacode/skillet/repo-onboarding/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 repo-onboarding

Your own site · 80×15
<a href="https://agentmods.dev/skills/jnmetacode/skillet/repo-onboarding"><img src="https://agentmods.dev/badge/skills/jnmetacode/skillet/repo-onboarding.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 613 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 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 $0.00048 $0.00613
Opus 5 $0.00024 $0.00307
Sonnet 5 $0.00010 $0.00123
Haiku 4.5 $0.00005 $0.00061

Measured 10d ago against content hash 121c37ee7847, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

repo-onboarding 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 10d 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.

skills/repo-onboarding/SKILL.md · 50 lines

How it starts

The opening of the file, as written. The whole thing — 50 lines — stays where its author put it; the contents beside it link to each section on GitHub.

repo-onboarding

Resist editing until you can answer: how do I run it, how do I test it, where does the change go, and what style does this house write in?

Procedure (15 minutes, in order)

  1. The README + manifest first. README.md, then the manifest (package.json / pyproject.toml / go.mod / Cargo.toml): name, scripts, dependencies. The scripts block is the repo telling you its verbs.
  2. Find the entry points. bin/main fields, src/index.*, cmd/, __main__.py. Trace one request/command end-to-end at skim depth — names only, no line-reading.
  3. Establish the test loop before touching anything. Run the test command; record how long it takes and whether it's green at HEAD. A red baseline changes everything you conclude later.
  4. Map the directories (one line each, only top two levels). Mark the ones that are generated/vendored so you never read them again.
  5. Sample the house style. Open the 2–3 most-recently-changed source files (git log --name-only -10): error handling pattern, naming, comment density, test structure. Your changes should be indistinguishable from these.
  6. Find the seams. Where does config enter? Where is I/O isolated? What is the one module everything imports? That module is load-bearing — changes there need the most care.
  7. Check the repo's own rules: CONTRIBUTING.md, CLAUDE.md, .github/ workflows (what CI actually enforces), lint configs.

Output

Write a short map (10–20 lines) before starting the actual task:

run:   npm start (src/cli.js)        test: npm test, ~6s, green at HEAD
flow:  cli.js → commands/* → store.js (all persistence) → index.json
style: ESM, no deps, errors thrown as plain Error, tests in test/*.test.js
care:  store.js is imported everywhere; schema changes ripple
rules: CI runs lint+test on 3 OS; commits are conventional

Keep it honest — list what you didn't look at, so later-you knows where the map has blank spots.

Read the full file on GitHub · 50 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. 10d ago First seen · 50 lines · 48 tokens per session scan A 121c37ee7847

Subscribe to this mod's changes

repo-onboarding is a skill published in the GitHub repository jnMetaCode/skillet (1 stars, last pushed yesterday), licensed MIT. It adds 48 tokens to every session and 613 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.

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