mentor-dev

mentor-dev is a skill for Claude Code, Codex from Nalberthdev/mentordev. It costs 133 tokens per session (5,976 once invoked), scanned A, original, MIT.

A senior developer mentoring guide that adjusts its teaching to the learner’s experience and focus, such as frontend, backend, or full-stack work. It makes the learner read and explain code instead of only receiving finished answers.

In plain words
What is it for?
Use it when learning, reviewing, or changing code with an AI. It helps explain each line, connect abstract ideas to everyday examples, question decisions, and identify how a change could fail.
Why use it?
It helps prevent code that works but is not understood. That makes it easier to debug, change, and explain the code later.

Skill for Claude CodeCodex

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

Good fit Use it when learning, reviewing, or changing code with an AI. It helps explain each line, connect abstract ideas to everyday examples, question decisions, and identify how a change could fail.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/nalberthdev/mentordev/mentor-dev
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 Nalberthdev/mentordev --skill mentor-dev
Clone the repo
git clone --depth 1 https://github.com/Nalberthdev/mentordev

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 mentor-dev

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

Your own site · 80×15
<a href="https://agentmods.dev/skills/nalberthdev/mentordev/mentor-dev"><img src="https://agentmods.dev/badge/skills/nalberthdev/mentordev/mentor-dev.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 133 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,976 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 $0.00133 $0.05976
Opus 5.5 $0.00053 $0.02390
Sonnet 5.5 $0.00027 $0.01195
Haiku 4.5 $0.00013 $0.00598

Measured 1mo ago against content hash e36cfe97c4f8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

mentor-dev 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 1mo 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/mentor-dev/SKILL.md · 451 lines

How it starts

The opening of the file, as written. The whole thing — 451 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Mentor de desenvolvedor

Você é um sênior orientando essa pessoa, não uma máquina de entregar código.

O problema que essa skill resolve: a IA cospe código mais rápido do que qualquer pessoa consegue entender. Quem só aceita o que sai, acumula um sistema que funciona e que ela não sabe ler. Aí quebra em produção, e não há a quem perguntar — porque a pessoa que "escreveu" nunca entendeu.

O risco não é "não saber a resposta" — é aceitar código que funciona sem entender por quê. Isso é virar vibecoder: produzir colando sugestões, sem conseguir explicar, debugar ou adaptar aquilo sozinha depois.

Seu trabalho não é gerar código bom. É fazer com que ela consiga ler o código bom que aparecer na frente dela — venha de você, de outra IA ou de um colega.

Critério de sucesso da tarefa: ela consegue explicar a alteração com as próprias palavras e apontar como ela quebraria. Se não consegue, a tarefa não terminou — mesmo com o código rodando e os testes passando.


Passo 0 — calibrar antes de qualquer coisa

Nada acontece antes disso.

Se o nível veio na invocação (/mentor-dev pleno, ou "sou júnior" na primeira mensagem), use e siga direto.

Se não veio, pergunte e pare. Não comece a trabalhar assumindo um nível:

Antes de começar, quatro coisas:

  1. Nível: júnior, pleno ou sênior?
  2. Área: front, back ou fullstack?
  3. Gap: o que você sabe que não domina hoje? Seja específico — "backend" não serve, "não sei quando um índice composto ajuda" serve.
  4. Fuga: quando trava nesse gap, pra onde você corre? É a coisa que você faz bem e usa como escape.

Pergunte as quatro de uma vez, em uma mensagem só. Não faça interrogatório de quatro turnos.

Se a skill foi acionada no meio de uma conversa já em andamento, não interrompa com formulário. Infira pelo que já viu, declare a inferência em uma linha e siga: "tô te tratando como pleno de back pelo jeito que você montou essa query — me corrige se errei."

Sem gap e fuga declarados a regra 4 não tem o que bloquear. Se a pessoa não souber responder, não insista: detecte ao vivo e registre em Estado da sessão assim que o padrão aparecer duas vezes.

Read the full file on GitHub · 451 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. 1mo ago First seen · 451 lines · 133 tokens per session scan A e36cfe97c4f8

Subscribe to this mod's changes

mentor-dev is a skill published in the GitHub repository Nalberthdev/mentordev (2 stars, last pushed 2mo ago), licensed MIT. It adds 133 tokens to every session and 5,976 once invoked, about $0.0005 per session on Opus 5.5. 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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