WorldCat MCP Server

An MCP (Model Context Protocol) server for searching WorldCat, the world's largest library catalog — 500M+ records from 100,000+ libraries worldwide.

Built with FastMCP and the WorldCat Discovery API v2.

Tools

Tool	Description
`worldcat_search`	Search by keyword, title, author, subject, ISBN, ISSN, OCLC number, or advanced CQL
`worldcat_get_record`	Get full bibliographic record with LCSH, LC/Dewey classification, physical description
`worldcat_get_editions`	Find other editions and formats of a work (hardcover, ebook, translations)
`worldcat_get_citations`	Get formatted citations in APA, Chicago, Harvard, MLA, and Turabian
`worldcat_search_by_subject`	Search specifically by Library of Congress Subject Headings
`worldcat_export_ris`	Export results as RIS (for Zotero, EndNote, etc.)
`worldcat_export_bibtex`	Export results as BibTeX

Rich metadata

Records include:

Library of Congress Subject Headings (LCSH)
LC Classification and Dewey Decimal numbers
Physical descriptions, edition statements
Publisher, place, and date
ISBN, ISSN, LCCN, OCLC numbers
Summaries/abstracts and table of contents
Online access URLs
Edition counts across libraries

Setup

1. Get WorldCat API credentials

You need a WSKey with wcapi scope from the OCLC Developer Network. Institutional access through a library is typically required.

2. Install

cd worldcat-mcp-server
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt

3. Add to Claude Desktop

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "worldcat": {
      "command": "/path/to/worldcat-mcp-server/venv/bin/python",
      "args": ["/path/to/worldcat-mcp-server/server.py"],
      "env": {
        "WORLDCAT_API_KEY": "your-wskey",
        "WORLDCAT_API_SECRET": "your-wskey-secret"
      }
    }
  }
}

Or if using Claude Code CLI:

claude mcp add worldcat \
  /path/to/worldcat-mcp-server/venv/bin/python \
  /path/to/worldcat-mcp-server/server.py \
  -e WORLDCAT_API_KEY=your-wskey \
  -e WORLDCAT_API_SECRET=your-wskey-secret

Usage examples

"Search WorldCat for books on the history of jazz"
"Find the full record for OCLC number 1234567890"
"What other editions exist for this book?"
"Get an APA citation for this WorldCat record"
"Search by LCSH subject heading 'African Americans -- History'"
"Export these results as RIS for Zotero"

License

MIT

worldcat-mcp-server