skills-x: Instructions file for Claude Code

CLAUDE.md

skills-x CLAUDE.md is an instructions file for Claude Code from castle-x/skills-x. It costs 518 tokens per session, scanned A, original, MIT.

A set of project instructions for Claude Code contributors to Skills-X, a Go command-line tool for downloading and managing AI-agent skills. It describes the project structure and common commands for building and testing it.

In plain words
What is it for?
Use it to build Skills-X, run its tests, update embedded skills, inspect its registry and discovery code, or create cross-platform binaries.
Why use it?
It gives coding agents the repository's expected commands, package locations, and skill-embedding process. This reduces mistakes when changing code or preparing a build.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md; mentions Claude Code.

This is castle-x/skills-x's own configuration. It tells Claude Code how to work on skills-x itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything skills-x configures →

Reuse

Borrowing it

Nothing to install: this file belongs to castle-x/skills-x. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/castle-x/skills-x/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/castle-x/skills-x

Made for: Claude Code.

Wrote this? Show the measurements

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README.md
[![agentmods](https://agentmods.dev/badge/instructions/castle-x/skills-x/claude-md.svg)](https://agentmods.dev/instructions/castle-x/skills-x/claude-md)
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<a href="https://agentmods.dev/instructions/castle-x/skills-x/claude-md"><img src="https://agentmods.dev/badge/instructions/castle-x/skills-x/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 518 This file is loaded in full into every session.
When invoked 518 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00518 $0.00518
Opus 5 $0.00259 $0.00259
Sonnet 5 $0.00104 $0.00104
Haiku 4.5 $0.00052 $0.00052

Measured 8d ago against content hash b3799c367ad5, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

skills-x CLAUDE.md 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 8d ago.

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.

CLAUDE.md · 59 lines

What it actually says

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

Skills-X is a Go-based CLI tool for downloading and managing AI agent skills. It supports multiple AI IDEs (Claude Code, Cursor, Windsurf, CodeBuddy) and distributes skills via npm and Go install.

Common Commands

# Build the binary
make build

# Run tests
make test

# Run a single test
go test -v ./cmd/skills-x/command/initcmd/...

# Install to ~/.local/bin
make install-local

# Build cross-platform binaries for npm release
make build-npm

# Build all platforms to bin/
make build-all

Architecture

  • CLI Framework: Uses Cobra (github.com/spf13/cobra)
  • Commands: list, init, tui (see cmd/skills-x/command/)
  • Core Packages:
    • pkg/registry/ - Skill registry (registry.yaml)
    • pkg/discover/ - Skill discovery
    • pkg/gitutil/ - Git utilities for cloning skills
    • pkg/versioncheck/ - Version checking against GitHub releases
  • Skills: Embedded in binary at cmd/skills-x/skills/skills/ via go:embed. Run make sync-skills before building to update embedded skills.
  • i18n: Translations in cmd/skills-x/i18n/locales/ (en.yaml, zh.yaml)

Development Workflow

This project uses a plan-first workflow (see .cursor/rules/development-workflow.mdc):

  1. Discussion Phase: When users提出需求, discuss the approach first
  2. Plan Confirmation: Wait for user to confirm the plan
  3. Execution Phase: Only start coding after explicit instructions like "开始开发" or "start development"
  4. Documentation: Save implementation plans to docs/ before coding

Key Files

  • cmd/skills-x/main.go - Entry point, registers commands
  • cmd/skills-x/command/initcmd/init.go - Download/install skills
  • cmd/skills-x/command/list/list.go - List available skills
  • cmd/skills-x/tui/ - Interactive TUI for skill management
  • pkg/registry/registry.yaml - Skill registry definition
Changes

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.

  1. 8d ago First seen · 59 lines · 518 tokens per session scan A b3799c367ad5

Subscribe to this mod's changes

skills-x CLAUDE.md is an instructions file published in the GitHub repository castle-x/skills-x (18 stars, last pushed 4mo ago), licensed MIT. It adds 518 tokens to every session, about $0.0026 per session on Opus 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 2026-08-30.

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