MCP Server Builder
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
Audit, design, categorize, distribute, and measure agent skills using lessons from Anthropic's Lessons from building Claude Code: How we use skills.
$ npx skills add majiayu000/spellbook --skill skill-audit -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install majiayu000/spellbook skill-audit --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/skill-audit .claude/skills/skill-audit && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .claude/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/majiayu000/spellbook/tree/main/skills/skill-auditType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add majiayu000/spellbook --skill skill-audit -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install majiayu000/spellbook skill-audit --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/skill-audit .agents/skills/skill-audit && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .agents/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add majiayu000/spellbook --skill skill-audit -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install majiayu000/spellbook skill-audit --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/skill-audit .cursor/skills/skill-audit && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .cursor/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/majiayu000/spellbook.git --path skills/skill-audit--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add majiayu000/spellbook --skill skill-audit -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install majiayu000/spellbook skill-audit --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/skill-audit .gemini/skills/skill-audit && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .gemini/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install majiayu000/spellbook skill-auditInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add majiayu000/spellbook --skill skill-audit -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/skill-audit .github/skills/skill-audit && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .github/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add majiayu000/spellbook --skill skill-audit -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install majiayu000/spellbook skill-audit --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/majiayu000/spellbook.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/skill-audit .opencode/skills/skill-audit && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "skill-audit" agent skill from https://github.com/majiayu000/spellbook/tree/main/skills/skill-audit into .opencode/skills/skill-audit/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-audit", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
skill-auditAudit, design, categorize, distribute, and measure agent skills using lessons from Anthropic's Lessons from building Claude Code: How we use skills.
Skill Audit is an agent skill from majiayu000/spellbook. Audit, design, categorize, distribute, and measure agent skills using lessons from Anthropic's Lessons from building Claude Code: How we use skills. Use when reviewing an existing skill, deciding whether a workflow deserves a skill, planning a skill library, turning team knowledge into skills, choosing skill categories, writing trigger descriptions, designing progressive disclosure, or planning skill marketplace and usage measurement.
Its SKILL.md is about 1.6k tokens, which your agent loads only when the skill is triggered. The skill folder holds 5 other files, including reference files and assets (for example `assets/skill-brief-template.md`, `references/skill-taxonomy.md` and `references/writing-and-operations.md`).
It sits in Agent Workflows. The repository describes itself as: Cross-runtime skills for Claude Code, Codex, and multi-agent workflows. The licence is MIT.
7 steps, taken from the step headings in SKILL.md.
Read from SKILL.md and the folder at commit ed52af7. It shows what the files ask for, not the result of running them.
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Links to these hosts (documentation or services it may open):
claude.comFrom URLs in SKILL.md, links to its own repository left out.
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Skill Audit loads about 1.6k tokens when it runs, and up to ~3.4k if it reads all its reference files. Until then it costs about 113 tokens; SKILL.md has 834 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
The full file from majiayu000/spellbook at commit ed52af7, republished under its MIT licence (© majiayu000). 834 words, ~1,602 tokens.
.claude/skills/skill-audit/SKILL.md (or your agent's skills folder). This skill also uses 3 other files; get the full folder from GitHub.Use this skill to audit existing skills, turn workflow knowledge into useful
agent skills, and review skill libraries at the strategy level. It complements
skill-creator: use this skill to decide what a skill should be, how it should
fit a library, and what needs improvement; use skill-creator when the user
wants the concrete SKILL.md implementation and eval loop.
This workflow is based on Anthropic's June 3, 2026 blog post, "Lessons from building Claude Code: How we use skills": https://claude.com/blog/lessons-from-building-claude-code-how-we-use-skills
A good skill is not "some markdown about a topic." It is a compact extension point that gives the agent non-obvious domain knowledge, reusable files, deterministic helpers, setup rules, verification habits, and guardrails at the moment they matter.
Create or improve a skill only when at least one of these is true:
Do not make a skill when the content only restates obvious coding behavior, generic best practices, or one-off instructions.
Read references/skill-taxonomy.md and classify the candidate into exactly one
primary category. If it appears to span several categories, tighten the scope or
split it.
Report:
Use assets/skill-brief-template.md for the output. Fill it with:
Keep SKILL.md focused on activation, decisions, and the main workflow. Move
details into support files:
references/ for tables, API conventions, taxonomy, playbooks, and long docsscripts/ for deterministic actions or repetitive checksassets/ for templates, report formats, starter files, or examplesagents/ for specialized subagent prompts when the repo supports themevals/ for realistic prompts and objective assertionsTell the agent exactly when to read each support file.
Read references/writing-and-operations.md when deciding:
When the user wants the skill built, pass the brief into skill-creator and ask
it to implement the files, generate realistic test prompts, and run validation.
If editing an existing skill, include the exact file paths and the smallest content changes needed. Do not rewrite unrelated skill behavior.
For agent-workflow, delivery, PR, automation, or high-impact skills, use
skill-lifeguard or apply the same five-element score:
Report each element as present, partial, missing, or deferred. A missing
element is not always a blocker, but it must be visible in the brief and patch
plan.
For advisory requests, answer with:
For repository work, actually create or update the files, then run the repo's skill validation command.
© majiayu000, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
SKILL.md and 3 other files (references, assets) in skills/skill-audit of majiayu000/spellbook.
Open the folder on GitHubat commit ed52af7
Skill Audit next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Skill Audit this skillmajiayu000/spellbook | 287 | — | ~1.6k | Automated safety check: Pass | MIT | |
| MCP Server Builderanthropics/skills | 180k | 63 repos | ~2.3k | Automated safety check: Pass | Apache-2.0 | |
| Hook Development for Claude Code Pluginsanthropics/claude-plugins-official | 38k | 10 repos | ~4.1k | Automated safety check: Notes | Apache-2.0 | |
| Using Superpowersfarm-fe/farm | 5.6k | 36 repos | ~1.4k | Automated safety check: Pass | MIT | |
| Executing Plans Inlineobra/superpowers | 297k | 2 repos | ~5.1k | Automated safety check: Pass | MIT | |
| Skill CreatorAzure/azqr | 796 | 89 repos | ~8.2k | Automated safety check: Pass | Apache-2.0 |
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
anthropics/claude-plugins-official
Explains how to write Claude Code plugin hooks, both prompt-based checks and bash commands, for events such as PreToolUse, Stop and SessionStart.
farm-fe/farm
A skill your agent uses when starting any conversation - establishes how to find and use skills, requiring Skill tool invocation before ANY response including clarifying questions
obra/superpowers
Has the agent carry out an implementation plan itself, task by task in the current session, keeping a ledger, proving each step with a test and ending with one whole-branch review.
Azure/azqr
Create new skills, modify and improve existing skills, and measure skill performance.
anthropics/claude-plugins-official
Explains how to write agents for Claude Code plugins: the markdown file with YAML frontmatter, trigger descriptions, model and color settings, and system prompt design.
majiayu000/spellbook
Audits and repairs how coding-agent Skills are owned, copied and exposed across runtimes, from canonical sources to quarantine and retirement.
majiayu000/spellbook
Scans a repository for real evidence and proposes, or on request writes, a small stack of root and scoped AGENTS.md files with validation commands and generated-file boundaries.
majiayu000/spellbook
Plans, produces or diagnoses evidence-backed product demo videos: script, capture plan, pacing checks and verified final media built on real product behavior.
majiayu000/spellbook
Single entry point that routes long or ambiguous agent tasks, checks live state, bounds autonomous loops and leaves a resumable handoff.
majiayu000/spellbook
Scans a repository, its lockfiles and node_modules for known malicious npm package versions and install-time indicators, using a read-only Python scanner.
majiayu000/spellbook
Product management helpers: a RICE scoring script, an interview transcript analyzer and PRD templates for prioritizing features, synthesizing research and writing requirements.
Categories
Audit, design, categorize, distribute, and measure agent skills using lessons from Anthropic's Lessons from building Claude Code: How we use skills. Skill Audit is an agent skill from majiayu000/spellbook. Audit, design, categorize, distribute, and measure agent skills using lessons from Anthropic's Lessons from building Claude Code: How we use skills.
Skill Audit fits situations like: reviewing an existing skill; deciding whether a workflow deserves a skill; planning a skill library; turning team knowledge into skills.
Run `npx skills add majiayu000/spellbook --skill skill-audit -a claude-code`. Or copy the skill folder (skills/skill-audit in majiayu000/spellbook) into .claude/skills/skill-audit in your project. Claude Code loads it when a task matches its description.
Run `npx skills add majiayu000/spellbook --skill skill-audit -a codex`. Or copy the skill folder (skills/skill-audit in majiayu000/spellbook) into .agents/skills/skill-audit in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add majiayu000/spellbook --skill skill-audit -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/skill-audit, .gemini/skills/skill-audit, .github/skills/skill-audit and .opencode/skills/skill-audit in your project.
SKILL.md names no scripts, command-line tools or credentials: Skill Audit is instructions for the agent only.
SKILL.md names 1 domain. As links in the text: claude.com. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
Skill Audit is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
About 1.6k tokens (SKILL.md is roughly 6.4k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 1.8k tokens, read only when the agent opens those files.
Skills that share tags, products or a category with Skill Audit: MCP Server Builder (anthropics/skills, 180k stars), Hook Development for Claude Code Plugins (anthropics/claude-plugins-official, 38k stars), Using Superpowers (farm-fe/farm, 5.6k stars) and Executing Plans Inline (obra/superpowers, 297k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
majiayu000 (a GitHub user) maintains it in majiayu000/spellbook, which has 287 GitHub stars. The repository holds 97 skills in this directory. The repository was last updated on October 8, 2026.
Source: majiayu000/spellbook on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.