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.
npx skills add catiicode/claude-code-awesome-skills --skill effective-cppgit clone --depth 1 https://github.com/catiicode/claude-code-awesome-skillsWrote 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.
[](https://agentmods.dev/skills/catiicode/claude-code-awesome-skills/effective-cpp)<a href="https://agentmods.dev/skills/catiicode/claude-code-awesome-skills/effective-cpp"><img src="https://agentmods.dev/badge/skills/catiicode/claude-code-awesome-skills/effective-cpp/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.
<a href="https://agentmods.dev/skills/catiicode/claude-code-awesome-skills/effective-cpp"><img src="https://agentmods.dev/badge/skills/catiicode/claude-code-awesome-skills/effective-cpp.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00205 | $0.03546 |
| Opus 5.5 | $0.00082 | $0.01418 |
| Sonnet 5.5 | $0.00041 | $0.00709 |
| Haiku 4.5 | $0.00020 | $0.00355 |
Grade A, and why
effective-cpp 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.
How it starts
The opening of the file, as written. The whole thing — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Effective C++ Development Guide
Best practices from Scott Meyers' three books, organized by priority for practical C++ development.
Sources: [EC] Effective C++ (55 Items) | [MEC] More Effective C++ (35 Items) | [EMC] Effective Modern C++ (42 Items)
Priority: IRON RULE (UB/crash/leak) > STRONG (correctness/maintainability) > GOOD (quality improvement)
C++ Baseline: C++11
Deep-dive references — read when working on a specific topic:
- references/iron-rules.md — Full code examples for all iron rules
- references/class-design.md — Class design, constructors/destructors, interfaces
- references/resource-management.md — RAII, smart pointers, Pimpl
- references/inheritance-templates.md — Inheritance, NVI, templates, traits
- references/move-semantics-lambdas.md — Move semantics, forwarding, lambdas
- references/concurrency.md — Threads, async, atomic, volatile
- references/performance.md — RVO, inlining, lazy/eager eval, compilation
- references/exceptions-interop.md — Exception safety, C interop, type deduction
Iron Rules — Violating These Causes UB, Crashes, or Leaks
| # | Rule | Key Point |
|---|---|---|
| 1 | RAII [EC-13, MEC-9, MEC-10] | Every resource owned by an object whose destructor releases it. No manual cleanup. Smart pointer members in constructors prevent partial-construction leaks. |
| 2 | Match new/delete forms [EC-16] | new→delete, new[]→delete[]. Mismatch = UB. Prefer containers over raw arrays. |
| 3 | Virtual destructor for polymorphic bases [EC-7] | Deleting derived via base pointer with non-virtual dtor = UB. Has virtual functions → needs virtual dtor. |
| 4 | No exceptions from destructors [EC-8, MEC-11] | Second exception during stack unwinding → std::terminate(). Wrap throws in try/catch. Provide separate close() for error handling. |
| 5 | No virtual calls in ctors/dtors [EC-9] | During base construction, dynamic type IS the base. Virtual calls resolve to base version, never derived. Pass info via ctor args. |
| 6 | No redefining non-virtual functions or default params [EC-36, EC-37] | Both are statically bound. Redefining creates confusing behavior depending on pointer type. Use NVI for defaults. |
| 7 | No polymorphic arrays [MEC-3] | sizeof(Base) ≠ sizeof(Derived) breaks pointer arithmetic. Use vector<unique_ptr<Base>>. |
| 8 | Smart pointer ownership [EMC-18–21] | unique_ptr (default) / shared_ptr (truly shared) / weak_ptr (observer). Never two shared_ptr from same raw pointer. Use make_unique/make_shared. Store new-ed objects in smart pointers immediately [EC-17]. |
| 9 | Correct copying [EC-11, EC-12, EMC-17] | Self-assignment safety (copy-and-swap). Copy ALL parts (members + base). Rule of Five: declare any special member → declare all five. |
| 10 | std::move/forward correctness [EMC-23, EMC-25] | move = unconditional rvalue cast. forward = conditional (universal refs). Apply on LAST use only. Never move const (silently copies). Never move return values (inhibits RVO). |
| 11 | atomic ≠ volatile [EMC-40] | std::atomic = thread safety. volatile = no optimization (hardware I/O). volatile provides ZERO thread safety in C++. |
| 12 | Exception safety basics [EC-29, MEC-13] | Catch by reference (never by value — slicing). Catch derived before base (first-fit matching). Every function: at least basic guarantee. |
What ships with it
9 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.
- README.md 4.9 KB
- references/class-design.md 13 KB
- references/concurrency.md 6.9 KB
- references/exceptions-interop.md 9.3 KB
- references/inheritance-templates.md 11 KB
- references/iron-rules.md 12 KB
- references/move-semantics-lambdas.md 8.9 KB
- references/performance.md 13 KB
- references/resource-management.md 9.3 KB
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.
- 1mo ago First seen · 206 lines · 205 tokens per session scan A 74287b167e48
effective-cpp is a skill published in the GitHub repository catiicode/claude-code-awesome-skills (1 stars, last pushed 7mo ago), licensed MIT. It adds 205 tokens to every session and 3,546 once invoked, about $0.0008 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.
Other skills, from other repositories
cpp-pro
Writes, optimizes, and debugs C++ applications using modern C++20/23 features, template metaprogramming, and high-performance systems techniques. Use when building or refactoring C++ code requiring concepts, ranges, coroutines, SIMD optimization, or careful memory management — or when addressing performance…
memory-safety-patterns
Implement memory-safe programming with RAII, ownership, smart pointers, and resource management across Rust, C++, and C. Use when writing safe systems code, managing resources, or preventing memory bugs.
re-cpp-abi
A tool for examining compiled modern C++ programs when the original source code is unavailable. It helps recover class information, virtual function tables, exception paths, and readable names from a binary file.
cuda-c-optimization
A guide for improving CUDA C programs, which run computations on NVIDIA GPUs. It covers GPU memory access, thread-block sizing, numerical stability, and debugging.
cpp
Comprehensive C/C++ programming reference covering everything from C11-C23 and C++11-C++23, system programming, CUDA GPU computing, debugging tools, Rust interop, and advanced topics. Use for: C/C++ questions, C/C++ interview preparation, modern language features, RAII/memory management, templates/generics, CUDA…
agent-cpp-expert
Specialist subagent: C and C++ development, modern C++ (C++17/20/23), CMake, systems programming, and memory management specialist. Use when writing C/C++ code, debugging memory issues, or building systems-level software. Trigger phrases: C++, C language, CMake, modern C++, systems programming, memory management…