package-registry-mcp: Instructions file for Claude Code

CLAUDE.md

package-registry-mcp CLAUDE.md is an instructions file for Claude Code from Artmann/package-registry-mcp. It costs 404 tokens per session, scanned A, original, MIT.

Repository instructions for an MCP server that lets AI assistants search NPM, Cargo, and NuGet package registries and retrieve package details. Package registries are online catalogues of reusable software libraries.

In plain words
What is it for?
Use them when developing or maintaining the server, building its output, formatting source code, or testing package searches, details, and version lists.
Why use it?
They explain how to install dependencies, build the server, format its code, and test individual tools. This reduces setup mistakes when working on the TypeScript and Bun project.

Instructions file for Claude Code

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

This is Artmann/package-registry-mcp's own configuration. It tells Claude Code how to work on package-registry-mcp 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 package-registry-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Artmann/package-registry-mcp. 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/Artmann/package-registry-mcp/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/Artmann/package-registry-mcp

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.

agentmods badge for package-registry-mcp CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/artmann/package-registry-mcp/claude-md.svg)](https://agentmods.dev/instructions/artmann/package-registry-mcp/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/artmann/package-registry-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/artmann/package-registry-mcp/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 404 This file is loaded in full into every session.
When invoked 404 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 $0.00404 $0.00404
Opus 5 $0.00202 $0.00202
Sonnet 5 $0.00081 $0.00081
Haiku 4.5 $0.00040 $0.00040

Measured 8d ago against content hash 9aabd6309aee, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

package-registry-mcp 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

CLAUDE.md · 61 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

This is a Model Context Protocol (MCP) server that enables AI assistants to search package registries (NPM, Cargo, NuGet) and retrieve up-to-date package information. The server exposes tools for searching packages and getting detailed package metadata.

Common Commands

# Install dependencies
bun install

# Build the server (outputs to dist/)
bun run build

# Format code with Prettier
bun run format

# Test individual MCP tools
bun tool <tool-name> <json-arguments>
# Examples:
# bun tool search-npm-packages '{"query": "react"}'
# bun tool get-npm-package-details '{"name": "react"}'
# bun tool list-npm-package-versions '{"name": "react", "limit": 50}'

Architecture

  • Runtime: Uses Bun as the primary runtime and build tool
  • Entry point: src/index.ts (currently contains placeholder code)
  • Build target: Node.js compatible output in dist/
  • Dependencies:
    • @modelcontextprotocol/sdk for MCP server implementation
    • zod for schema validation
  • Package manager: Yarn (specified in packageManager field)

TypeScript Configuration

The project uses strict TypeScript with modern ESNext features and bundler module resolution. Key settings:

  • Strict mode enabled with additional safety checks
  • Bundle-compatible module resolution
  • ESNext target for latest JavaScript features

Code Style Guidelines

  • Separate imports of third party packages and local files
  • Sort import in alphabetical order, based on the package name or import path. Separate packages and local file imports with an empty line.

Development Workflow

  • Run bun format and bun typecheck when you've finished making changes
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 · 61 lines · 404 tokens per session scan A 9aabd6309aee

Subscribe to this mod's changes

package-registry-mcp CLAUDE.md is an instructions file published in the GitHub repository Artmann/package-registry-mcp (39 stars, last pushed 9mo ago), licensed MIT. It adds 404 tokens to every session, about $0.0020 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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