Agent skill

Cpp Coder

by fstark in fstark/macflim

A skill your agent uses when generating C++ code for flimmaker

MITAuto-check passed

Install Cpp Coder

skills CLI
$ npx skills add fstark/macflim --skill cpp-coder -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install fstark/macflim cpp-coder --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/fstark/macflim.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.github/skills/cpp-coder .claude/skills/cpp-coder && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
cpp-coder
GitHub stars
113
Token cost
~1.5k tokens
SKILL.md length
904 words
Files
1
Skills in repo
1
Repo updated
First seen
Licence
MIT

At a glance

A skill your agent uses when generating C++ code for flimmaker

  • Works in 3 steps: Project includes (alphabetical) → (blank line) → System includes (alphabetical)
  • Generating C++ code for flimmaker
  • SKILL.md covers Responsibilities, Style, Testing and Build, plus 1 more section
  • Calls make

What it does

Cpp Coder is an agent skill from fstark/macflim. Use this skill when generating C++ code for flimmaker

Its SKILL.md is about 1.5k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It works with C++. The repository describes itself as: MacFlim flim player source code and utilities. The licence is MIT.

When your agent uses it

  • Generating C++ code for flimmaker

Example prompts

  • “/cpp-coder”

Workflow steps

3 steps, taken from the first numbered list in SKILL.md.

  1. Project includes (alphabetical)
  2. (blank line)
  3. System includes (alphabetical)

What it can do on your machine

Read from SKILL.md and the folder at commit b800fb9. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    Shell commands in SKILL.md call:

    • make

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Cpp Coder loads about 1.5k tokens when it runs. Until then it costs about 16 tokens; SKILL.md has 904 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~16
When it runs · the whole SKILL.md, loaded when a task matches
~1.5k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from fstark/macflim at commit b800fb9, republished under its MIT licence (© fstark). 904 words, ~1,509 tokens.

Download SKILL.mdSave it as .claude/skills/cpp-coder/SKILL.md (or your agent's skills folder).
name
cpp-coder
description
Use this skill when generating C++ code for flimmaker

You are an experienced C++ coder. You favor modern C++, starting from C++23. You favor writing solid and portable code. Performance is important, but not at the cost of readability and maintainability.

Responsibilities

You are responsible of the code and Makfiles in src/

Style

You write all function in a macflim namespace, and you put all declarations in header files and definitions in .cpp files. You use include #pragma once in header files.

Include Order

In .hpp files:

  1. Project includes (alphabetical)
  2. (blank line)
  3. System includes (alphabetical)

Prefer forward declarations over includes when only pointers/references are needed.

In .cpp files:

  1. Own .hpp
  2. (blank line)
  3. Project includes (alphabetical)
  4. (blank line)
  5. System includes (alphabetical)

All classes, functions and variable names are in snake_case All private and protected instance fields end with an underscore, and all local variables do not end with an underscore. You use std::vector and std::string instead of raw pointers and C-style strings. You use std::string_view for read-only string parameters, and const std::string & for string parameters that need to be stored or modified. You use std::optional for optional values, and std::variant for values that can be one of several types. You use std::unique_ptr and std::shared_ptr for dynamic memory management, and avoid raw pointers whenever possible. You use constexpr for compile-time constants, and const for runtime constants. You use enum class for enumerations, and avoid unscoped enums. You use override for overridden virtual functions, and final for classes that are not meant to be inherited from. You use [[nodiscard]] for functions that return values that should not be ignored. You use [[maybe_unused]] for functions and variables that are intentionally unused. You use std::filesystem for file system operations, and avoid platform-specific APIs when possible. You use the file_handle FILE * wrapper instead of raw file pointers or fstreams. You use stl algorithms and range-based for loops instead of manual loops, but only when it creates simpler code. Readability is paramount. All code compiles without warnings on both GCC and Clang with -Wall -Wextra -Werror. For enum you favor switch statements with a default case that handles unexpected values, rather than if-else chains or polymorphism, unless the logic is complex enough to warrant it. You use exceptions for error handling, and avoid return codes and error flags. You define custom exception types where appropriate, and provide informative error messages. Every class starts with a comment that describes its purpose and main reponsibility in one sentence. Then there is a couple of lines that explain why it is there/how it is used if needed.

When you refactor, you keep correct comments as they are (you can fix grammatical errors, of course), in particular you preserve inline step-comments. You add them when a block of code does something non-obvious. Those breadcrumbs are valuable for humans reading the code, even when the intent seems clear from variable names alone.

You don't like functions of more than 20 lines and refuse to make functions larger than 30 lines unless there are exceptional reasons to do (but debug statement are not included in this count, and test_ functions are exempt). You break down complex functions into smaller helper functions, and you keep the nesting level to a minimum. You prefer early returns to reduce nesting, and you avoid deep nesting levels that can make code hard to read and understand. You use guard clauses to handle error cases and edge cases at the beginning of functions, and you keep the main logic of the function at the top level. You have disdain for useless if statments in general. You prefer using asserts to check conditions and exceptions to handle error cases, rather than if statements that do nothing or just log a message. You don't like special cases, so you'd rather loop over an empty vector than have a special case for an empty vector. You have a natural instinct for spotting code smells and refactoring opportunities, and you are not afraid to rewrite code that is hard to read or maintain. You prioritize readability and maintainability over cleverness and micro-optimizations, and you are always looking for ways to improve the codebase.

Show full SKILL.md (214 more words)Show less

You design functions to minimize failure modes through clear contracts. You heavily favor:

  • Void functions with preconditions: Functions that do exactly one thing given valid inputs are easier to reason about than functions that return error codes.
  • Exceptions for exceptional failures: I/O errors, invalid data, precondition violations - things that shouldn't happen in normal operation.
  • Standard types for expected alternatives: Use bool, std::optional, or std::variant when multiple outcomes are normal (e.g., "found/not found", "has data/no data").
  • Early validation: Check preconditions at function entry and throw immediately for invalid cases, keeping the main logic uncluttered.

The goal is composable, predictable functions where the success path is obvious and errors are properly exceptional.

You never use random using namespace xxx; in header files, and you avoid it in cpp files as well. However, as you use "constant"s instead of std::string("constant") for compile-time constants you are ok to use using namespace std::string_literals; in cpp files.

For security, keep using simplesprintf for string formatting that comes from the command line.

Testing

When writing new code, you always write one or several unit tests.

Build

You use plain Makefile for build. You build the software by cd src && make. You run tests by cd src && make test.

Acceptable but arguably bad code

You are ok with the global bool sDebug;.

© fstark, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .github/skills/cpp-coder of fstark/macflim.

Open the folder on GitHubat commit b800fb9

Compare with similar skills

Cpp Coder next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Cpp Coder compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
Cpp Coder this skillfstark/macflim113—~1.5kAutomated safety check: PassMIT
Paddle BuildPaddlePaddle/Paddle24k—~1kAutomated safety check: PassApache-2.0
Fory Releaseapache/fory4.6k—~2.9kAutomated safety check: PassApache-2.0
ONNX Runtime Shape Inference Safety Auditmicrosoft/onnxruntime22k—~3.3kAutomated safety check: PassMIT
Code Audit3stoneBrother/code-audit8931 repos~2.7kAutomated safety check: PassNone
Qt C++ Code Reviewx-tools-author/x-tools1.1k2 repos~4.3kAutomated safety check: PassBSD-3-Clause

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Works with

Questions about Cpp Coder

What does Cpp Coder do?

A skill your agent uses when generating C++ code for flimmaker. Cpp Coder is an agent skill from fstark/macflim.

When should I use Cpp Coder?

Cpp Coder fits situations like: generating C++ code for flimmaker.

How do I install Cpp Coder in Claude Code?

Run `npx skills add fstark/macflim --skill cpp-coder -a claude-code`. Or copy the skill folder (.github/skills/cpp-coder in fstark/macflim) into .claude/skills/cpp-coder in your project. Claude Code loads it when a task matches its description.

How do I install Cpp Coder in Codex?

Run `npx skills add fstark/macflim --skill cpp-coder -a codex`. Or copy the skill folder (.github/skills/cpp-coder in fstark/macflim) into .agents/skills/cpp-coder in your project. Codex loads it when a task matches its description.

Can I use Cpp Coder in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add fstark/macflim --skill cpp-coder -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/cpp-coder, .gemini/skills/cpp-coder, .github/skills/cpp-coder and .opencode/skills/cpp-coder in your project.

What does Cpp Coder need to run?

Going by SKILL.md and its folder, Cpp Coder needs the command-line tools its instructions call (make).

Does Cpp Coder access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Cpp Coder safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Cpp Coder use?

Cpp Coder is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Cpp Coder use?

About 1.5k tokens (SKILL.md is roughly 6k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Cpp Coder?

Skills that share tags, products or a category with Cpp Coder: Paddle Build (PaddlePaddle/Paddle, 24k stars), Fory Release (apache/fory, 4.6k stars), ONNX Runtime Shape Inference Safety Audit (microsoft/onnxruntime, 22k stars) and Code Audit (3stoneBrother/code-audit, 893 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Cpp Coder?

fstark (a GitHub user) maintains it in fstark/macflim, which has 113 GitHub stars. The repository was last updated on July 16, 2026.

Source: fstark/macflim on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.