claude-skills is a large collection of reusable skills, commands, plugins, and supporting resources for coding agents across engineering, business, research, compliance, and productivity work. It is used by people who want agents such as Claude Code, Codex, Gemini CLI, or Cursor to follow specialized workflows. The catalogue contains selected skills and settings from the collection.
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 alirezarezvani/claude-skills --skill challengegit clone --depth 1 https://github.com/alirezarezvani/claude-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/alirezarezvani/claude-skills/challenge)<a href="https://agentmods.dev/skills/alirezarezvani/claude-skills/challenge"><img src="https://agentmods.dev/badge/skills/alirezarezvani/claude-skills/challenge/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/alirezarezvani/claude-skills/challenge"><img src="https://agentmods.dev/badge/skills/alirezarezvani/claude-skills/challenge.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Agent Snooping · line 1 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00077 | $0.01530 |
| Opus 5.5 | $0.00031 | $0.00612 |
| Sonnet 5.5 | $0.00015 | $0.00306 |
| Haiku 4.5 | $0.00008 | $0.00153 |
Grade A, and why
challenge 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 today.
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 — 182 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/em:challenge — Pre-Mortem Plan Analysis
Command: /em:challenge <plan>
Systematically finds weaknesses in any plan before reality does. Not to kill the plan — to make it survive contact with reality.
The Core Idea
Most plans fail for predictable reasons. Not bad luck — bad assumptions. Overestimated demand. Underestimated complexity. Dependencies nobody questioned. Timing that made sense in a spreadsheet but not in the real world.
The pre-mortem technique: imagine it's 12 months from now and this plan failed spectacularly. Now work backwards. Why?
That's not pessimism. It's how you build something that doesn't collapse.
When to Run a Challenge
- Before committing significant resources to a plan
- Before presenting to the board or investors
- When you notice you're only hearing positive feedback about the plan
- When the plan requires multiple external dependencies to align
- When there's pressure to move fast and "figure it out later"
- When you feel excited about the plan (excitement is a signal to scrutinize harder)
The Challenge Framework
Step 1: Extract Core Assumptions
Before you can test a plan, you need to surface everything it assumes to be true.
For each section of the plan, ask:
- What has to be true for this to work?
- What are we assuming about customer behavior?
- What are we assuming about competitor response?
- What are we assuming about our own execution capability?
- What external factors does this depend on?
Common assumption categories:
- Market assumptions — size, growth rate, customer willingness to pay, buying cycle
- Execution assumptions — team capacity, velocity, no major hires needed
- Customer assumptions — they have the problem, they know they have it, they'll pay to solve it
- Competitive assumptions — incumbents won't respond, no new entrant, moat holds
- Financial assumptions — burn rate, revenue timing, CAC, LTV ratios
- Dependency assumptions — partner will deliver, API won't change, regulations won't shift
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.
- today Changed · +181 lines · +77 tokens per session eb04f1e49bae
- 1mo ago First seen · 1 lines · 0 tokens per session scan A d56303f02a82
challenge is a skill published in the GitHub repository alirezarezvani/claude-skills (28,607 stars, last pushed yesterday), licensed MIT. It adds 77 tokens to every session and 1,530 once invoked, about $0.0003 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 2026-09-03.
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systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
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Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…
insight-error-page
Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…