metmuseum-mcp: Instructions file for Claude Code

CLAUDE.md

metmuseum-mcp CLAUDE.md is an instructions file for Claude Code from mikechao/metmuseum-mcp. It costs 917 tokens per session, scanned A, original, MIT.

Repository instructions for developing metmuseum-mcp, an MCP server that provides access to the Metropolitan Museum of Art collection.

In plain words
What is it for?
Use them to install dependencies, build the server, run type checks and linting, and understand its standard or HTTP server modes.
Why use it?
They give an AI coding agent the project context and commands needed to make changes and check the result correctly.

Instructions file for Claude Code

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

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

Reuse

Borrowing it

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

Made for: Claude Code.

Wrote this? Show the measurements

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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.

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Per session 917 This file is loaded in full into every session.
When invoked 917 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 $0.00917 $0.00917
Opus 5 $0.00458 $0.00458
Sonnet 5 $0.00183 $0.00183
Haiku 4.5 $0.00092 $0.00092

Measured 10d ago against content hash c2d7ebf9aea7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

metmuseum-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 10d 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 · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

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

Project Overview

This is a Model Context Protocol (MCP) server that provides access to the Metropolitan Museum of Art Collection API. It exposes tools for searching and browsing artworks, plus an interactive MCP App for visual exploration.

Development Commands

# Install dependencies (requires pnpm)
corepack enable
pnpm install

# Build the project (includes syncing versions and bundling UI apps)
pnpm run build

# Type checking
pnpm run typecheck

# Linting (with auto-fix)
pnpm run lint

# Run both lint and typecheck
pnpm run check

Running the Server

  • Stdio mode (default): node dist/index.js or npx -y metmuseum-mcp
  • HTTP mode: node dist/index.js --http (listens on localhost:3001/mcp)

Environment variables for HTTP mode:

  • PORT (default: 3001)
  • HOST (default: 127.0.0.1)
  • ALLOWED_HOSTS (default: localhost,127.0.0.1)
  • MET_API_TIMEOUT_MS (default: 10000)

Architecture

Entry Point

  • src/index.ts - Main entry point that determines transport (stdio or HTTP) and starts the server

Server Setup

  • src/MetMuseumServer.ts - Creates and configures the MCP server, registers tools and resources
  • src/server-utils.ts - Transport layer utilities for stdio and streamable HTTP

API Layer

  • src/api/MetMuseumApiClient.ts - HTTP client for the Met Museum Collection API with rate limiting (80 req/s)

Tools (MCP Protocol)

  • src/tools/ListDepartmentsTool.ts - Lists all museum departments
  • src/tools/SearchMuseumObjectsTool.ts - Searches objects with filters (department, images, dates, etc.)
  • src/tools/GetObjectTool.ts - Fetches detailed object data including optional base64 image
  • src/tools/OpenMetExplorerTool.ts - Launches the interactive explorer app

MCP Apps (UI)

Two HTML/JavaScript apps bundled via esbuild:

  • src/ui/met-explorer/ - Main browsing app with search, filtering, pagination
  • src/ui/object-details/ - Standalone object detail view

Read the full file on GitHub · 112 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.

  1. 10d ago First seen · 112 lines · 917 tokens per session scan A c2d7ebf9aea7

Subscribe to this mod's changes

metmuseum-mcp CLAUDE.md is an instructions file published in the GitHub repository mikechao/metmuseum-mcp (35 stars, last pushed 4mo ago), licensed MIT. It adds 917 tokens to every session, about $0.0046 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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