cpp-coding-standards

A set of modern C++ coding and review guidelines based on the C++ Core Guidelines, covering safer resource handling, types, const usage, and clear design.

In plain words
What is it for?
Use it when writing, reviewing, refactoring, or making design decisions in C++17, C++20, or C++23 projects.
Why use it?
It helps prevent common C++ errors and makes code easier to understand by encouraging resources to be managed automatically and intent to be explicit.

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/junmystery/agent-guidance-python/cpp-coding-standards
Any agent
npx skills add JunMystery/Agent-Guidance-Python --skill cpp-coding-standards
Clone the repo
git clone --depth 1 https://github.com/JunMystery/Agent-Guidance-Python

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 6,025 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 98% 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 $0.00048 $0.06025
Opus 5 $0.00024 $0.03012
Sonnet 5 $0.00010 $0.01205
Haiku 4.5 $0.00005 $0.00602

Measured yesterday against content hash f870b47d3493, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cpp-coding-standards 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 yesterday.

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

98% identical to cpp-coding-standards — 3 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.

skills/cpp-coding-standards/SKILL.md · 725 lines

How it starts

The opening of the file, as written. The whole thing — 725 lines — stays where its author put it; the contents beside it link to each section on GitHub.

C++ Coding Standards (C++ Core Guidelines)

Comprehensive coding standards for modern C++ (C++17/20/23) derived from the C++ Core Guidelines. Enforces type safety, resource safety, immutability, and clarity.

When to Use

  • Writing new C++ code (classes, functions, templates)
  • Reviewing or refactoring existing C++ code
  • Making architectural decisions in C++ projects
  • Enforcing consistent style across a C++ codebase
  • Choosing between language features (e.g., enum vs enum class, raw pointer vs smart pointer)

When NOT to Use

  • Non-C++ projects
  • Legacy C codebases that cannot adopt modern C++ features
  • Embedded/bare-metal contexts where specific guidelines conflict with hardware constraints (adapt selectively)

Cross-Cutting Principles

These themes recur across the entire guidelines and form the foundation:

  1. RAII everywhere (P.8, R.1, E.6, CP.20): Bind resource lifetime to object lifetime
  2. Immutability by default (P.10, Con.1-5, ES.25): Start with const/constexpr; mutability is the exception
  3. Type safety (P.4, I.4, ES.46-49, Enum.3): Use the type system to prevent errors at compile time
  4. Express intent (P.3, F.1, NL.1-2, T.10): Names, types, and concepts should communicate purpose
  5. Minimize complexity (F.2-3, ES.5, Per.4-5): Simple code is correct code
  6. Value semantics over pointer semantics (C.10, R.3-5, F.20, CP.31): Prefer returning by value and scoped objects

Philosophy & Interfaces (P., I.)

Key Rules

Rule Summary
P.1 Express ideas directly in code
P.3 Express intent
P.4 Ideally, a program should be statically type safe
P.5 Prefer compile-time checking to run-time checking
P.8 Don't leak any resources
P.10 Prefer immutable data to mutable data
I.1 Make interfaces explicit
I.2 Avoid non-const global variables
I.4 Make interfaces precisely and strongly typed
I.11 Never transfer ownership by a raw pointer or reference
I.23 Keep the number of function arguments low

Read the full file on GitHub · 725 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. yesterday First seen · 725 lines · 48 tokens per session scan A f870b47d3493

Subscribe to this mod's changes

cpp-coding-standards is a skill published in the GitHub repository JunMystery/Agent-Guidance-Python (2 stars, last pushed 1mo ago), licensed MIT. It adds 48 tokens to every session and 6,025 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 98% identical to cpp-coding-standards, differing in 3 lines, and is treated as a copy.

Related

Other skills, from other repositories

common-feedback-reporter

Pre-write audit for skill violations: checks planned code against loaded skill anti-patterns before any file write. Use when writing Flutter/Dart/TS code or editing SKILL.md files with active project skills. Load as composite; on auto-fixed violation, also load +common/common-learning-log.

HoangNguyen0403/agent-skills-standard · 63 tokens

common-exploit-verification

Enforce "No Exploit, No Report" policy with PoC construction standards, false-positive filtering, and evidence collection per vulnerability class across backend, frontend, and mobile. Use when validating security findings, constructing exploit proofs, filtering false positives, or writing pentest findings.

HoangNguyen0403/agent-skills-standard · 61 tokens

common-session-retrospective

Analyze conversation corrections to detect skill gaps and prepare targeted skill-library maintenance tasks. Use after any session with user corrections, rework, or retrospective requests. After finding correction loops, also load +common/common-learning-log to persist mistake entries to AGENTSLEARNING.md.

HoangNguyen0403/agent-skills-standard · 59 tokens

common-store-changelog

Generate user-facing release notes for the App Store and Google Play from git history (App Store <=4000 chars, Google Play <=500). Use when generating release notes, app store changelog, play store release, or "what's new" text for a mobile app.

HoangNguyen0403/agent-skills-standard · 60 tokens

common-code-review

Conduct high-quality, persona-driven code reviews. Use when reviewing PRs, critiquing code quality, or analyzing changes for team feedback.

HoangNguyen0403/agent-skills-standard · 32 tokens

common-workflow-writing

Rules for writing concise, token-efficient workflow and skill files. Prevents over-building that requires costly optimization passes. Use when creating or editing workflow files, SKILL.md files, or new skill definitions.

HoangNguyen0403/agent-skills-standard · 45 tokens