Unpaywall Server

An MCP (Model Context Protocol) server for the Unpaywall API — open-access availability for 120M+ scholarly articles.

Built with FastMCP.

Tools

Tool	Description
unpaywall_lookup	Look up open-access availability by DOI — returns OA status, PDF/landing page URLs, license, all OA locations
unpaywall_search	Search 120M+ article titles with OA filtering and pagination
unpaywall_export_ris	Export results as RIS (for Zotero, EndNote, etc.)
unpaywall_export_bibtex	Export results as BibTeX

What you get

• Open-access status and OA type (gold, green, hybrid, bronze)
• Best OA location with direct PDF link
• All OA locations across repositories and publishers
• Journal OA status, ISSN, publisher info
• Author lists, publication dates, DOIs
• License information per location

Setup

1. Get your email ready

Unpaywall requires an email address as your API identifier (no API key needed). See the Unpaywall API docs.

2. Install

pip install unpaywall-mcp-server

Or install from source:

cd unpaywall-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": {
    "unpaywall": {
      "command": "uvx",
      "args": ["unpaywall-mcp-server"],
      "env": {
        "UNPAYWALL_EMAIL": "[email protected]"
      }
    }
  }
}

Or if using Claude Code CLI:

claude mcp add unpaywall \
  uvx unpaywall-mcp-server \
  -e [email protected]

Usage examples

• "Is there an open-access version of DOI 10.1038/nature12373?"
• "Search Unpaywall for open-access papers on CRISPR gene editing"
• "Export these results as RIS for Zotero"
• "Find OA articles about climate change mitigation"

License

MIT