Top 10 Skills for Claude Code and Codex CLI

The real skill isn’t getting AI to answers! But to do so in a manner that fits our budgets and fulfils our requirements. It’s guiding it with clear context and turning its output into useful action. This list is built around a simpler idea. Instead of searching through thousands of skills, you start with the exact problem you’re facing. Each common frustration is matched to a specific skill, so you can install only what you need and make tools like Claude Code or Codex CLI more useful. Table of contents1. For AI/software development2. For agent harnesses3. For getting AI to ask clarifying questions4. For getting shorter, simpler code5. For saving tokens6. For recalling previous sessions7. For Agent workflows8. For mapping unfamiliar codebase9. For retaining context in conversation resets10. For checking if a skill is safeHow to install Claude/Codex SkillsWhere to start?Frequently Asked Questions 1. For AI/software development obra/superpowers | ★ 267,733 · 23,919 forks Moreover, an agentic skills framework & software development methodology that works. Instead of jumping into code, the agent asks you questions until it understands what you want, shows you the plan in pieces short enough to read, and waits for your approval before building anything. What makes this skill special? It asks first and builds second, which is the opposite of the default behaviour It writes tests as it goes, rather than promising them later Once approved, it can work on its own for hours without drifting off the plan Nothing to remember after installing. It kicks in by itself. Works with: Both Claude Code and Codex CLI. In fact, perfect for anyone who has watched an agent confidently build the wrong thing. 2. For agent harnesses affaan-m/ECC | ★ 238,146 · 36,166 forks If everyone on your team has their agent configured differently and nobody can reproduce anyone else’s results, one skill won’t help. You need a shared setup. Consequently, this is that: a large, opinionated bundle covering planning, code review, build fixes, security, and architecture, all installed in one go. What makes this skill special? It’s built around roles (the planner, the reviewer etc.) rather than a pile of unrelated tools In addition, a built-in security scanner checks your own setup for leaked secrets and risky settings You choose which coding standards apply to which projects, instead of forcing them everywhere The documentation is honest about which features work on which tools Works with: Best with Claude Code. Meanwhile, Codex is supported through a separate setup step. Best for teams, not individuals. 3. For getting AI to ask clarifying questions multica-ai/andrej-karpathy-skills | ★ 200,098 · 20,585 forks Your agent quietly decides what you meant, runs with it, and you find out twenty minutes later. For example, this repo has 200,000 stars for a single file that targets exactly that. Similarly, it takes Andrej Karpathy’s widely shared post about where coding agents go wrong and turns each complaint into a rule. The rule What it fixes Think before coding Guessing instead of asking, hiding confusion Keep it simple Writing 1,000 lines of code where 100 would do Change only what’s needed Rewriting parts that were never requested to change Work toward a clear goal Instructions that are too vague for the agent to verify its own work What makes this skill special? It’s one file with nothing else attached, so it’s the cheapest thing on this list to try The fourth rule is the one that changes results. “Fix the bug” becomes “write a test that shows the bug, then make it pass.” Give the agent something it can check itself against and it stops guessing. It tells you how to know it’s working with questions arriving before the work rather than apologies after! Works with: Claude Code and Cursor out of the box. The first thing most people should install. 4. For getting shorter, simpler code DietrichGebert/ponytail | ★ 97,139 · 5,337 forks You ask for a date picker. While, your agent installs an extra library, writes a wrapper for it, adds a stylesheet, and starts a discussion about timezones. Instead, this skill gives you the single line of built-in code that already does the job. Nevertheless, the idea is the senior engineer who looks at your fifty lines, says nothing, and replaces them with one. It’s also the only entry here that published a test of itself against itself. In short, twelve real feature requests on a real project, with and without the skill: Compared to no skill Code written Cost Time With ponytail −54% −20% −27% With a plain “keep it short” instruction −33% −21% −30% What makes this skill special? As a result, roughly half the code, for a fifth less money and a quarter less waiting In fact, simply telling the agent “keep it short” gets you part of the way and quietly drops a safety check doing it. This doesn’t. Consequently, the numbers are honest about their limits: the saving is huge where the agent was about to over-build, and near zero where the code was already simple. Works with: Claude Code and Codex CLI. Perfect if you’re the one who has to maintain the result. 5. For saving tokens JuliusBrussee/caveman | ★ 96,300 · 5,500 forks Agents pad with sentences like “Sure! Furthermore, I’d be happy to help with that. The issue you’re experiencing is most likely…” you pay for every word of that! In contrast, this skill makes the agent talk like a caveman. Same answer, a third of the words. Code, commands, paths and error messages come through untouched. Only the words gets squeezed. What makes this skill special? Keeps your language. Write Portuguese, get caveman response in Portuguese. Also shortens commit messages and code review comments Honest about limits: savings shrink on unattended coding work, sometimes to nothing JetBrains tested it across 86 tasks and found answer quality unchanged Works with: Claude Code and Codex CLI supported. Perfect if you’re watching your usage limits. Caveman or ponytail? Both promise savings but at opposite ends. Ponytail shrinks the code. Caveman shrinks the words around it. caveman ponytail Shrinks The explanation The code Your code after Unchanged About half the size Saving 65% fewer output tokens when chatting 54% less code, 20% cheaper, 27% faster Best when Chatting, debugging, asking questions Building features you’ll maintain 6. For recalling previous sessions thedotmack/claude-mem | ★ 89,815 · 7,819 forks If you start every session re-explaining last week, this fixes it. It quietly records what happens as you work, stores it on your own machine, and lets the agent look things up later by meaning rather than exact wording. Ask clarifying questions like “what did we decide about the login flow?” and it finds the answer. What makes this skill special? Most memory tools fail by dumping everything back into the conversation and slowing it to a crawl. This one searches first and fetches only what’s relevant. Everything stays local, on your machine It comes with a simple web page where you can read your own history back The agent decides when to look something up, so you don’t have to prompt it Works with: Claude Code only. Best for projects that run for weeks, not one-off tasks. 7. For Agent workflows addyosmani/agent-skills | ★ 82,313 · 8,844 forks If you’d like a professional workflow but don’t want to design one yourself, this hands you a ready-made one. It breaks work into six stages you trigger by name: define what you’re building, plan it, build it, test it, review it, ship it. Two extras cover speeding up a slow website and simplifying messy code. What makes this skill special? Each stage carries a principle rather than a checklist: agree what you’re building before you build it, small pieces one at a time, tests as proof It picks the right stage by itself based on what you’re doing, so you can also just work normally There’s an automatic mode that runs the whole build in one pass after you approve the plan. It still tests everything and still stops if something breaks. Works with: Claude Code and Codex CLI, plus 70+ other tools. Perfect for solo developers who want structure without inventing it. 8. For mapping unfamiliar codebase Egonex-AI/Understand-Anything | ★ 77,730 · 6,526 forks You’ve just joined a team and the project is 200,000 lines long. Every other entry here improves how the agent writes. This one improves how you read. Point it at a project and it produces an interactive map of how everything connects, which you explore in your browser. What makes this skill special? Click any part of the map and get a plain-English explanation of what it does and what depends on it The stated goal is a map that teaches you how the pieces fit, not one that shows off how complicated the project is There’s a live demo on their site, so you can see what you’re getting before installing anything Just as useful before a big cleanup, when what you need is a map rather than a list of changes Works with: Claude Code, Codex CLI, and about ten other tools. Best for inherited projects and getting oriented. 9. For retaining context in conversation resets OthmanAdi/planning-with-files | ★ 26,001 · 2,178 forks Every agent forgets. Clear the chat, hit a limit, or close your laptop, and the plan goes with it. This skill writes the plan, the findings, and the progress into three ordinary files on your computer, then feeds them back in every time you type. The conversation resets. The plan doesn’t. What makes this skill special? It happens automatically, so nobody has to remember to save anything An optional final check stops the agent declaring the job done before it actually is Three plain text files you can open and read yourself, not a hidden database Their own testing shows an agent picking up where it left off in about 5 exchanges instead of 13. Worth knowing those tests were run by the author, not independently. Works with: Claude Code, Codex CLI, and 60+ other tools. Perfect for work measured in days, and the best option for Codex users who want memory. 10. For checking if a skill is safe NVIDIA/SkillSpector | ★ 14,278 · 1,194 forks Install this before anything else on this list, including this list. A skill is a set of instructions your agent will follow, with access to your files and your accounts. Research NVIDIA cites found that “roughly one in four skills contains a security flaw, and one in twenty looks deliberately malicious”. This is a free scanner from NVIDIA that reads a skill before you install it and tells you whether it’s safe. What makes this skill special? Checks against 68 known bad patterns, including skills that quietly steal data or hand themselves more access than they should have Give it a link, a folder, or a single file. It handles all three. You get a simple score out of 100 and a plain summary, not a wall of security jargon Run it again later and it only flags what’s new Works with: Everything. It’s a scanner, not a skill, so it doesn’t care which agent you use. For everyone, and especially anyone about to install a skill from someone they’ve never heard of. How to install Claude/Codex Skills Most of these take under a minute. Two commands cover almost everything. In Claude Code, type this in the chat: /plugin marketplace add / /plugin install In Codex CLI, run this in your terminal: codex plugin marketplace add / codex plugin add There’s also a universal installer that works across 70+ tools if you’d rather not remember which is which: npx skills add / Skill Claude Code Codex CLI superpowers /plugin install superpowers@claude-plugins-official /plugins, then search superpowers ECC /plugin marketplace add https://github.com/affaan-m/ECC Run their setup script (see README) andrej-karpathy-skills /plugin marketplace add multica-ai/andrej-karpathy-skills Copy the skill file into your Codex settings manually ponytail /plugin marketplace add DietrichGebert/ponytail codex plugin marketplace add DietrichGebert/ponytail caveman npx skills add JuliusBrussee/caveman npx skills add JuliusBrussee/caveman claude-mem npx claude-mem install Not available agent-skills /plugin marketplace add addyosmani/agent-skills codex plugin marketplace add addyosmani/agent-skills Understand-Anything /plugin marketplace add Egonex-AI/Understand-Anything One-line installer on their README planning-with-files /plugin marketplace add OthmanAdi/planning-with-files npx skills add OthmanAdi/planning-with-files SkillSpector See their README (standalone scanner) Same If you use both Claude Code and Codex, runkids/skillshare keeps one set of skills in sync across both, so you’re not maintaining two copies. Where to start? There’s no single skill that can be the best for all (though I’d recommend the Nvidia profile inspector to all. If your agent keeps writing far more code than the job needed, start with andrej-karpathy-skills or ponytail. If the problem is that there’s no process at all, agent-skills hands you one, and superpowers goes further and rebuilds how you work from the ground up. Whatever you choose, scan it with SkillSpector first. Three or four skills is the practical limit anyway. Past that they start overlapping and you lose track of which one is doing what. Read more: Top 5 Agentic Skill for Writing Frequently Asked Questions Q1. Do I need to know how to code to use these?A. No coding is required. Installation involves copying one or two commands, and you do not need to write or edit code to use these skills effectively. Q2. Which one should I install if I only install one?A. Install andrej-karpathy-skills. It is a simple, affordable file that prevents agents from over-building or changing files you did not ask them to modify. Q3. Do these actually work on Codex CLI, or is that just marketing?A. Eight of ten support Codex. Check the “Works with” line in each section, as claude-mem and andrej-karpathy-skills have specific limitations regarding Codex compatibility. Q4. How many should I install?A. Install three or four skills covering behavior, planning, memory, and scanning. Adding more creates redundancy and makes it difficult to predict which skill will control the agent. Q5. Is installing skills from strangers risky?A. Yes, skills have file access and can contain security flaws. Only use reputable repositories with named authors and always scan code you did not write yourself. Studying, evaluating, and explaining AI systems for over 6 years. “𝘖𝘯𝘤𝘦 𝘮𝘦𝘯 𝘵𝘶𝘳𝘯𝘦𝘥 𝘵𝘩𝘦𝘪𝘳 𝘵𝘩𝘪𝘯𝘬𝘪𝘯𝘨 𝘰𝘷𝘦𝘳 𝘵𝘰 𝘮𝘢𝘤𝘩𝘪𝘯𝘦𝘴 𝘪𝘯 𝘵𝘩𝘦 𝘩𝘰𝘱𝘦 𝘵𝘩𝘢𝘵 𝘵𝘩𝘪𝘴 𝘸𝘰𝘶𝘭𝘥 𝘴𝘦𝘵 𝘵𝘩𝘦𝘮 𝘧𝘳𝘦𝘦. 𝘉𝘶𝘵 𝘵𝘩𝘢𝘵 𝘰𝘯𝘭𝘺 𝘱𝘦𝘳𝘮𝘪𝘵𝘵𝘦𝘥 𝘰𝘵𝘩𝘦𝘳 𝘮𝘦𝘯 𝘸𝘪𝘵𝘩 𝘮𝘢𝘤𝘩𝘪𝘯𝘦𝘴 𝘵𝘰 𝘦𝘯𝘴𝘭𝘢𝘷𝘦 𝘵𝘩𝘦𝘮.” — 𝖥𝗋𝖺𝗇𝗄 𝖧𝖾𝗋𝖻𝖾𝗋𝗍, 𝖣𝗎𝗇𝖾