Agent Skills

Public collection of Agent Skills used by Arthur across Codex, Claude Code, and other compatible coding agents.

Install the CLI

Install the native CLI through the npm registry with Node.js 18 or newer:

npm install --global @arthjean/skills

Bun can run the package without a separate Node.js installation:

bunx --bun --package @arthjean/skills@latest arthur-skills \
  plan --provider claude --provider codex

With Node.js available, pnpm and Bun can also install the global launcher:

pnpm add --global @arthjean/skills
bun add --global @arthjean/skills

The package contains the native binaries for every supported platform. It does not compile Rust or clone this repository during installation.

Review the immutable plan, then apply the same provider selection:

arthur-skills plan --provider claude --provider codex
arthur-skills install --provider claude --provider codex
arthur-skills doctor

Update the CLI by installing the latest package:

npm install --global @arthjean/skills@latest

Install skills only

Install from GitHub with the skills CLI:

bunx skills add arthjean/skills

Inspect the catalog without installing anything:

bunx skills add arthjean/skills --list

Install one or more specific skills:

bunx skills add arthjean/skills --skill meta-code --skill write-prd

Install globally instead of in the current project:

bunx skills add arthjean/skills --global

The skills CLI installs skills, but not the Claude and Codex agent definitions bundled with arthur-skills.

Standalone installer

Use the standalone installer when a JavaScript runtime or package manager is unavailable. The arthur-skills binary embeds the complete runtime catalog and requires no JavaScript runtime after installation. Rust 1.95.0 is pinned at the repository root.

# Pin acquisition to a release, then verify the downloaded checksum file before execution.
ARTHUR_SKILLS_VERSION=v0.2.1
curl --proto '=https' --tlsv1.2 -LsSf \
  "https://github.com/arthjean/skills/releases/download/${ARTHUR_SKILLS_VERSION}/arthur-skills-installer.sh" \
  -o arthur-skills-installer.sh
curl --proto '=https' --tlsv1.2 -LsSf \
  "https://github.com/arthjean/skills/releases/download/${ARTHUR_SKILLS_VERSION}/sha256.sum" \
  -o sha256.sum
grep ' arthur-skills-installer.sh$' sha256.sum > arthur-skills-installer.sh.sha256
if command -v sha256sum >/dev/null; then
  sha256sum --check arthur-skills-installer.sh.sha256
else
  shasum -a 256 --check arthur-skills-installer.sh.sha256
fi
sh arthur-skills-installer.sh

Use a published tag and its sha256.sum manifest rather than an unpinned main-branch installer. For local development:

cargo run -p arthur-skills -- --help
cargo build --release -p arthur-skills

On Windows, use the signed release inputs from PowerShell:

$Version = "v0.2.1"
$Base = "https://github.com/arthjean/skills/releases/download/$Version"
Invoke-WebRequest "$Base/arthur-skills-installer.ps1" -OutFile arthur-skills-installer.ps1
Invoke-WebRequest "$Base/sha256.sum" -OutFile sha256.sum
$Checksum = Get-Content sha256.sum | Where-Object { $_ -match ' arthur-skills-installer\.ps1$' }
if (@($Checksum).Count -ne 1) { throw "Installer checksum entry missing" }
$Expected = $Checksum.Split()[0].ToLowerInvariant()
$Observed = (Get-FileHash arthur-skills-installer.ps1 -Algorithm SHA256).Hash.ToLowerInvariant()
if ($Observed -ne $Expected) { throw "Installer checksum mismatch" }
& .\arthur-skills-installer.ps1

The installation command surface is plan, install, status, doctor, update, uninstall, adopt, and recover.

Repository maintainers can inspect and synchronize the vendored third-party skills without changing an installed workflow:

arthur-skills upstream check
arthur-skills upstream sync --dry-run
arthur-skills upstream sync --yes

upstreams.toml records each canonical repository, tracked branch, and skill path. upstreams.lock.json pins the imported source revision, Git tree, and vendored content hash. The updater clones each repository once into staging, blocks on local drift or removed upstream paths, and replaces only clean pinned snapshots. The regular update command remains offline and reconciles installations exclusively to the catalog embedded in the current binary.

Interactive terminals use Ratatui in an inline viewport. --plain, ARTHUR_SKILLS_PLAIN=1, or TERM=dumb selects the keyboard-driven line renderer. Redirected streams and CI=true never prompt; pass explicit --provider values and --yes for mutations. --json emits one schema-v1 envelope and never initializes Ratatui. NO_COLOR disables color without changing the interaction mode.

The installer writes canonical skills under $HOME/.agents/skills, Claude activations and agents under $HOME/.claude/{skills,agents}, Codex agents under ${CODEX_HOME:-$HOME/.codex}/agents, and its versioned receipt under $HOME/.agents/.arthur-workflow/receipt.json. On Windows, $HOME falls back to %USERPROFILE%, and Claude activations are managed copies because creating symlinks can require Developer Mode or elevated privileges. Unix uses relative Claude symlinks. The installer owns only entries recorded in its receipt or transferred from a verified Vercel Skills v3 lock. adopt transfers exactly the skills a verified v3 lock entry proves, and never claims an agent, a support file, or any path the lock does not name. A foreign entry that matches the catalog byte for byte but carries no proof is reported as matching_unmanaged_without_proof: move or remove that path, then run plan again. Conflicts and drift without an ownership proof are never overwritten or removed. --dry-run scans and serializes the same plan without creating directories, locks, staging, timestamps, or a receipt.

One request produces one decision. plan, install --dry-run, update --dry-run, the interactive review, and the executor all consume that same decision, so a confirmed plan applies exactly what it displayed. A managed asset whose bytes differ from both its receipt proof and the bundled catalog is reported as drifted and preserved: restore or move it, then run plan again. When the content on disk already matches the catalog and only the receipt is stale, the plan shows one write_receipt operation that reconciles the installation metadata; a second run is a no-op and rewrites nothing.

Every ownership claim is revalidated under the transaction lock. A destination whose fingerprint changed between the plan and the lock stops the command with stale_lifecycle_decision, exit code 3, and zero mutation: review a new plan. A claim the transaction does not rewrite, such as an adopted entry or a receipt-only convergence, is verified once more immediately before the receipt commit; a change detected there rolls the transaction back with exit code 5, or keeps the journal and backups for recover when the compensation cannot restore a tampered path. No receipt ever records a fingerprint the transaction could not revalidate.

The JSON v1 status set is closed: success, noop, blocked, failed, or recovery_required. Every diagnostic contains code, severity, message, an optional source_id for a legacy lock entry, mutually exclusive path_utf8 or path_bytes_hex, and remediation. Every plan entry carries reason_code and ownership_basis among receipt, verified_legacy, created_in_transaction, and none; only a provable basis can enter the receipt. Exit codes are stable: 0 success or no-op, 2 usage or missing non-interactive decisions, 3 conflict, 4 invalid environment, 5 transaction or integrity failure, 130 SIGINT, and 143 SIGTERM.

Repository structure

  • skills/ contains every installable skill. Each skill has its own SKILL.md and optional references, scripts, or assets.
  • agents/claude/ mirrors the agents optimized for Claude Code.
  • agents/codex/ mirrors the agents optimized for Codex, including their evaluation suite.
  • crates/arthur-skills/ contains the native CLI and build-time catalog validator.
  • npm/ contains the dependency-free package launcher. Release staging injects the verified native binaries.
  • shared/claude/skills/_shared/ contains packaged Claude workflow support documents.

The skills CLI does not install these agent files.

The CLI discovers skills recursively, so the repository can be installed directly through the GitHub shorthand above.

License

Original material authored by Arthur is available under the MIT License. Bundled upstream skills and components retain their respective licenses and copyrights. See THIRD_PARTY.md.