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 agentmods add instructions/jakesterns/agent-skills/claude-mdgit clone --depth 1 https://github.com/jakesterns/agent-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/instructions/jakesterns/agent-skills/claude-md)<a href="https://agentmods.dev/instructions/jakesterns/agent-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/jakesterns/agent-skills/claude-md.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00305 | $0.00305 |
| Opus 5 | $0.00152 | $0.00152 |
| Sonnet 5 | $0.00061 | $0.00061 |
| Haiku 4.5 | $0.00030 | $0.00030 |
Grade B, and why
agent-skills CLAUDE.md scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
The MCP server is configured globally at `~/.claude/settings.json`. It exposes a `find_skill(query)` tool that searches the installed skill library. What it actually says
Agent Skills — Development Guide
This is the agent-skills monorepo. It contains:
packages/core/— Install pipeline, security scanner, marketplace adapters, manifest managementpackages/cli/— TypeScript CLI (npx agent-skills)packages/rag/— RAG semantic search with LanceDB and 16 embedding backendspackages/mcp-server/— MCP stdio server exposingfind_skillto any MCP-capable agentextension/— VS Code extension with 6 React webviews
Build
npm install
npm run build --workspaces
Test CLI
AGENT_SKILLS_HOME="$(pwd)" node packages/cli/dist/index.js help
MCP Server
The MCP server is configured globally at ~/.claude/settings.json. It exposes a find_skill(query) tool that searches the installed skill library.
Key files
skills.json— Skill manifest (installed skills registry)Skillfile— Declarative skill dependencies (like package.json for skills)marketplace.json— Adapter config, scan rules, install defaultsscripts/official-vendors.json— 520 vendor orgs for catalog crawlingscripts/filter-dimensions.json— Tool/role/topic keyword rulesextension/data/catalog.json— Pre-built catalog of 2,499 official vendor skills
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.
- 5d ago First seen · 36 lines · 305 tokens per session scan B d3c8fce3e958
agent-skills CLAUDE.md is an instructions file published in the GitHub repository jakesterns/agent-skills (2 stars, last pushed 3mo ago), licensed MIT. It adds 305 tokens to every session, about $0.0015 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.