@cyanheads/met-museum-mcp-server

Public Hosted Server: https://met-museum.caseyjhand.com/mcp

Overview

The Metropolitan Museum of Art's public Collection API. Search the collection by keyword and filters, or browse it by department and update date, then fetch full object records — metadata, provenance, and CC0 open-access images — from any MCP client. Runs as a stdio process, a local Streamable HTTP server, or the public hosted endpoint above.

Tools

Related MCP server: open-museum-mcp

Capability reference

met_list_departments tool

• No input; returns all 19 curatorial departments, each a numeric departmentId with its displayName (e.g., "Egyptian Art")

• departmentId values are the valid input for the departmentId filter on met_search_collections and met_list_objects

• Typed errors: upstream_blocked, upstream_unavailable (the Met answered 500/502/503/504 through every retry), and retry_deadline_exceeded (the call's time budget ran out)

met_search_collections tool

• Keyword q (required), matched across all text fields unless matchField narrows it to "title" or "tags". "*" matches every object, for a search by filters alone; an accession number from a label ranks its object first. Plus filters: departmentId, medium (a case-sensitive classification as the Met spells it — "Paintings", not "Oil on canvas"), dateBegin/dateEnd (integer years, negative = BCE, set together), one geoLocation, hasImages, isOnView, and isHighlight (true only)

• departmentId 7 (The Cloisters) and 17 (Medieval Art) share one search result set at the Met: each page keeps only the requested department's IDs, while total and paging count both, so a page can hold fewer than limit IDs; a notice says so, and met_list_objects gives exact department membership

• Up to 500 IDs per page (default 20), paged by offset / nextOffset through the first 10,000 matches only; total still reports the full count, with a notice when it exceeds 10,000

• Zero matches is a result, not an error: total: 0 with a notice saying whether the keyword matches nothing or the filters removed every match, and which filters to correct or drop. Every result echoes the applied query as effectiveQuery

• Typed errors: invalid_date_range, invalid_filter (a blank q, medium, or geoLocation), invalid_department, upstream_blocked, upstream_unavailable, retry_deadline_exceeded

met_list_objects tool

• Filters departmentId (from met_list_departments) and updatedSince (YYYY-MM-DD — records created or revised on or after that day), alone or together; with neither, the whole collection (over 500,000 IDs). Up to 500 IDs per page (default 20), in ascending order, paged by offset / nextOffset with no depth limit

• Typed errors: invalid_department, invalid_date (an impossible date such as 2026-02-30), upstream_blocked, upstream_unavailable, retry_deadline_exceeded; an empty list is a result, not an error, with a notice naming the filters, and every result echoes the applied filters as effectiveQuery

• Each list is cached for up to an hour, so a record revised within the last hour may not appear yet

met_get_object tool

• 1–20 IDs per call, from met_search_collections or met_list_objects; a repeated ID is fetched and returned once

• Partial success: per-ID errors land in failed[], and the call fails only when every ID does — all_not_found when every ID was a 404, upstream_blocked when the Met's firewall refused a request, retry_deadline_exceeded when every fetch ran out of the call's time budget, upstream_unavailable when a fetch met a Met API outage, and all_failed otherwise; records past a 60,000-byte structuredContent budget are listed in deferred[] with their sizes, to re-request

• isPublicDomain / hasCC0Image gate image URLs — non-public-domain objects return empty primaryImage, primaryImageSmall, and additionalImages; sparse fields are empty or null, never fabricated

• includeImages: true attaches the CC0 web-display image (about 600 px on the long edge) of the first 3 returned records that have one, as image content after a caption naming the object, and images[] gives each returned record's outcome (attached, no_cc0_image, over_cap, unavailable). The bytes ride content[] only, so a client that passes the model only structuredContent won't show them

• The Artist line carries the full attribution and role — artistPrefix ("Style of"), the name, artistSuffix, and artistRole ("Patron") — so a follower's work or a patron never reads as the named artist's own; rightsAndReproduction names the rights holder on the copyrighted works that carry one, beside accessionYear

• metadataDate is the record's last revision, the timestamp met_list_objects updatedSince compares; departmentId resolves the record's department name (five differ from met_list_departments) to the ID met_list_objects and met_search_collections take, or null when the name is not recognized

• The search index can list IDs the object endpoint no longer serves, so a 404's guidance is to drop the ID rather than search for it again

Features

Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.

Met Museum-specific:

• 500K+ artworks spanning 5,000 years from the Met's public collection API

• CC0 open-access data from The Metropolitan Museum of Art — free to use without permission or attribution

• Parallel batch fetching with configurable concurrency for met_get_object

• Linked data on every object — Getty ULAN and AAT URLs, Wikidata entity URLs for artists, tags, and works

• A 403 from the Met's firewall surfaces on every tool as upstream_blocked, non-retryable: the block covers the server's address for minutes, so the recovery is to wait and send fewer requests

• A 500, 502, 503, or 504 that outlasts the retries surfaces on every tool as upstream_unavailable; once every fetch in flight has failed without the Met answering any ID, met_get_object stops requesting the rest of the batch, so a 5xx outage costs at most MET_BATCH_CONCURRENCY × 4 requests (20 at the default) however many IDs were asked for

• No error carries the Met's HTML or JSON error page — an HTTP failure reaches the caller as its code, message, and status, or, inside a met_get_object batch, as that ID's failed[] message

Agent-friendly output:

• Provenance on every record — isPublicDomain and hasCC0Image flags distinguish CC0 objects from works with inaccessible images, so agents can reason about what they can actually display

• Partial failure reporting — met_get_object returns objects and failed arrays so callers receive successful records alongside structured per-ID error context

• Truncation signaling — met_search_collections and met_list_objects return total, returned, truncated, remaining, nextOffset, and the resolved offset; the text marks each page (truncated), (complete), or (offset beyond result set), and search adds (window end) for a page that stops at its 10,000-match window short of total

• Byte-budget disclosure — met_get_object reports deferred[] records with their sizes when a batch exceeds its serialized-response budget, so callers can size a follow-up call precisely

Getting started

Public Hosted Instance

A public instance is available at https://met-museum.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP:

{
  "mcpServers": {
    "met-museum-mcp-server": {
      "type": "streamable-http",
      "url": "https://met-museum.caseyjhand.com/mcp"
    }
  }
}

Self-Hosted / Local

Add the following to your MCP client configuration file.

{
  "mcpServers": {
    "met-museum-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/met-museum-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "met-museum-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/met-museum-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Or with Docker:

{
  "mcpServers": {
    "met-museum-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "-e", "MCP_TRANSPORT_TYPE=stdio",
        "ghcr.io/cyanheads/met-museum-mcp-server:latest"
      ]
    }
  }
}

For Streamable HTTP, set the transport and start the server:

MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 bun run start:http
# Server listens at http://localhost:3010/mcp

Prerequisites

• Bun v1.4.0 or higher (or Node.js v24+).

• No API key required — the Met Collection API is public and unauthenticated.

Installation

1. Clone the repository:

git clone https://github.com/cyanheads/met-museum-mcp-server.git

2. Navigate into the directory:

cd met-museum-mcp-server

3. Install dependencies:

bun install

4. Configure environment:

cp .env.example .env
# edit .env as needed (all vars are optional)

Configuration

All configuration is validated at startup via Zod schemas in src/config/server-config.ts.

See .env.example for the full list of optional overrides.

Running the server

Local development

• Build and run:

  # One-time build
  bun run rebuild
  
  # Run the built server
  bun run start:stdio
  # or
  bun run start:http

• Run checks and tests:

  bun run devcheck   # Lint, format, typecheck, security
  bun run test       # Vitest test suite
  bun run lint:mcp   # Validate MCP definitions against spec

Docker

docker build -t met-museum-mcp-server .
docker run --rm -p 3010:3010 met-museum-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/met-museum-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.

Project structure

Development guide

See CLAUDE.md for development guidelines and architectural rules. The short version:

• Handlers throw, framework catches — no try/catch in tool logic

• Use ctx.log for request-scoped logging, ctx.state for tenant-scoped storage

• Register new tools via the arrays in createApp() in src/index.ts

• Wrap external API calls: validate raw → normalize to domain type → return output schema; never fabricate missing fields

Contributing

Issues are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

Data attribution

Data from The Metropolitan Museum of Art Collection API (CC0).

License

Apache-2.0 — see LICENSE for details.