zotero-pdf-mcp

An MCP server that gives Claude access to a Zotero library over the web API, including the ability to look at the PDFs — rendered pages, not just extracted text, so figures, gels, micrographs and layout are visible.

Existing Zotero MCP servers return extracted text only. This one renders pages to PNG and returns them as image content, which is the difference between an assistant that can read a paper's prose and one that can read its figures.

Design constraints

• Web API only. Talks to api.zotero.org and never to the local Zotero client on localhost:23119. If your Zotero is set to download attachments on demand, going through the local client would make it fetch and retain files you have deliberately offloaded to Zotero storage. This server cannot cause that.

• Nothing written to disk. PDF bytes are held in memory, capped at four documents, and discarded when the process exits.

• Read-only. Every request is a GET; there are no write operations of any kind. A read-only API key is sufficient.

• The credential never leaves Zotero. File downloads redirect to a storage host; the server re-issues that request without the Zotero headers so your API key is not forwarded to a third party.

Attachments stored in Zotero File Storage can be fetched. Linked files cannot — their bytes only ever existed on the machine that added them. zotero_item_info reports which is which.

Related MCP server: mcp-zotero

Tools

Configuration

Add to ~/Library/Application Support/Claude/claude_desktop_config.json inside the existing mcpServers object:

"zotero-pdf": {
  "command": "/opt/homebrew/bin/uvx",
  "args": ["--from", "git+https://github.com/USER/zotero-pdf-mcp", "zotero-pdf-mcp"],
  "env": {
    "ZOTERO_API_KEY": "your_read_only_key",
    "ZOTERO_LIBRARY_ID": "your_numeric_userid",
    "ZOTERO_LIBRARY_TYPE": "user"
  }
}

Use the absolute path to uvx (which uvx) rather than the bare command — GUI-launched processes often do not inherit your shell's PATH, and that is the most common reason an MCP server silently fails to start.

For a private repo, use git+ssh://git@github.com/USER/zotero-pdf-mcp so the fetch authenticates with your SSH key.

Environment

Never commit the key. It belongs in the config's env block and nowhere else.

Usage

Ask for text before pictures — rendering pages is far more expensive than extracting text:

Find the Vujanovic 2017 paper in my library, pull the text, then show me the figures from pages 4 and 5.

Licence

MIT.