Cran Extrachecks

Q: What is a Claude Code skill and how does the Cran Extrachecks skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Cran Extrachecks is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the General category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: General · Sub-category: general-misc · Last updated: 2026-05-21

type:review

Prepare R packages for CRAN submission by checking for common ad-hoc requirements not caught by devtools::check(). Use when: (1) Preparing a package for first CRAN release, (2) Preparing a package update for CRAN resubmission, (3) Reviewing a package to ensure CRAN compliance, (4) Responding to CRAN reviewer feedback. Covers documentation requirements, DESCRIPTION field standards, URL validation, examples, and administrative requirements.

From the source SKILL.md

Help R package developers prepare packages for CRAN submission by systematically checking for common ad-hoc requirements that CRAN reviewers enforce but devtools::check() doesn't catch.

What this skill does

Cran Extrachecks is a community-contributed Claude Code skill in the general-misc sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/cran-extrachecks/ and loads when your prompt matches the skill's trigger.

When to invoke it: Use when: (1) Preparing a package for first CRAN release, (2) Preparing a package update for CRAN resubmission, (3) Reviewing a package to ensure CRAN compliance, (4) Responding to CRAN reviewer feedback. Covers documentation requirements, DESCRIPTION field standards, URL validation, examples, and administrative requirements.

Who uses this skill

The Cran Extrachecks Claude Code skill is built for Claude Code users and developers across all disciplines looking for general-purpose AI assistance. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 117,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/cran-extrachecks
curl -L https://claudskills.com/skills/cran-extrachecks/SKILL.md \
  -o ~/.claude/skills/cran-extrachecks/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/cran-extrachecks/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/cran-extrachecks/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\cran-extrachecks\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the Cran Extrachecks Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/cran-extrachecks/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the Cran Extrachecks skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the Cran Extrachecks skill?

Use Cran Extrachecks when your Claude Code task falls under the General category — specifically in the general misc area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Cran Extrachecks" or describe the task and let Claude pick). Browse related skills at /category/general/.

What is a Claude Code skill and how does the Cran Extrachecks skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Cran Extrachecks is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the General category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/posit-dev/skills/blob/HEAD/r-lib/cran-extrachecks/SKILL.md
Author: posit-dev

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

posit-dev. (2026). Cran Extrachecks [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/cran-extrachecks/

BibTeX

@misc{cran-extrachecks-2026,
  author    = {posit-dev},
  title     = {Cran Extrachecks [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/cran-extrachecks/}
}

Embed this skill

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Badge

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