What is skillkit CLAUDE.md?

A Python library for giving AI agents packaged areas of expertise they can discover and use when needed. It supports skill files, multiple sources, several agent frameworks, and different language models.

Building agents that find skills from projects, personal folders, or plugins; load them progressively; run their scripts with controls; and connect them to frameworks such as LangChain or CrewAI.

It avoids putting every instruction into an agent’s context at the start, while adding checks that help prevent unsafe file access.

How maxvaega/skillkit configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to maxvaega/skillkit. 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/maxvaega/skillkit/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/maxvaega/skillkit

Made for: Claude Code.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/maxvaega/skillkit/claude-md/github.svg)](https://agentmods.dev/instructions/maxvaega/skillkit/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/maxvaega/skillkit/claude-md"><img src="https://agentmods.dev/badge/instructions/maxvaega/skillkit/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/maxvaega/skillkit/claude-md"><img src="https://agentmods.dev/badge/instructions/maxvaega/skillkit/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 4,749 This file is loaded in full into every session.

When invoked 4,749 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.

Model	Per session	Once invoked
Fable 5.1	$0.04749	$0.04749
Opus 5.5	$0.01900	$0.01900
Sonnet 5.5	$0.00950	$0.00950
Haiku 4.5	$0.00475	$0.00475

Measured 2mo ago against content hash 3e68a30bb715, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

skillkit 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 2mo 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 · 329 lines

How it starts

The opening of the file, as written. The whole thing — 329 lines — stays where its author put it; the contents beside it link to each section on GitHub.

skillkit

skillkit is a Python library that implements Anthropic's Agent Skills functionality, enabling LLM-powered agents to autonomously discover and utilize packaged expertise. The library provides:

Multi-source skill discovery from personal directories, project directories, and plugins
SKILL.md parsing with YAML frontmatter validation
Progressive disclosure pattern (metadata loading → on-demand content)
Framework integrations (LangChain, LlamaIndex, CrewAI, Haystack, Google ADK)
Security features (path traversal prevention, permission checks)
Model-agnostic design supporting Claude, GPT, Gemini, and open-source LLMs

Development Approach

This project follows a Vertical Slice MVP strategy to deliver working functionality quickly:

v0.1 (Released): Core functionality + LangChain integration (sync only)
v0.2 (Released): Async support + multi-source discovery + plugin integration
v0.3 (Released): Script execution with security controls
v1.0 (Planned): Additional framework integrations + production polish + comprehensive documentation + 90% test coverage

Current Focus (v0.4)

The v0.4 release implements advanced progressive disclosure with intelligent caching:

LRU Content Cache: In-memory cache with configurable size (default: 100 entries)
Mtime-based Invalidation: Automatic cache invalidation when SKILL.md files are modified
Argument Normalization: Whitespace variations map to same cache entry for maximum efficiency
Thread-Safe Concurrency: Per-skill asyncio locks enable safe parallel invocations
Cache Management API: get_cache_stats(), clear_cache() for monitoring and control
Performance: <1ms cache hits vs 10-25ms first invocation (up to 25x faster)
Memory Efficient: ~2.1KB per cached entry, ~5MB cache overhead
High Hit Rate: 80%+ cache hit rate achievable with typical usage patterns
Script Integration: Script detection integrates with Level 2 caching lifecycle
Backward Compatible: 100% compatible with v0.1/v0.2/v0.3 APIs

Read the full file on GitHub · 329 lines

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.

2mo ago First seen · 329 lines · 4,749 tokens per session scan A 3e68a30bb715

Subscribe to this mod's changes

skillkit CLAUDE.md is an instructions file published in the GitHub repository maxvaega/skillkit (147 stars, last pushed 9mo ago), licensed MIT. It adds 4,749 tokens to every session, about $0.0190 per session on Opus 5.5. 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.

Building agents LLM LangChain agents ai prompt prompt-engineering

skillkit CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
skillkit CLAUDE.mdmaxvaega/skillkit	Instructions file	147	9mo ago	MIT	A	4,749	Claude Code
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

skillkit: Instructions file for Claude Code