Unpaywall

live Research

Find free legal copies of paywalled papers by DOI. No API key — uses a polite-pool email.

1 tools
0ms auth
free tier 50 calls/day
🔑 Authentication

Unpaywall requires a contact email (polite-pool identifier). The gateway can supply one, or BYO via _email query param.

Config with credentials 
{
  "mcpServers": {
    "pipeworx-unpaywall": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://gateway.pipeworx.io/unpaywall/mcp?_email=you%40example.com"
      ]
    }
  }
}

Get an API key →

Tools

get_oa

Given a DOI, fetch open-access status and the best free legal copy if one exists. Returns is_oa, oa_status (gold | green | hybrid | bronze | closed), best location (URL, host type, license), and journ

No parameters required.

▶ Try it

Test with curl

The gateway speaks JSON-RPC 2.0 over HTTP POST. You can test any pack directly from the terminal.

List available tools
bash 
curl -X POST https://gateway.pipeworx.io/unpaywall/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'
Call a tool
bash 
curl -X POST https://gateway.pipeworx.io/unpaywall/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"get_oa","arguments":{}}}'

Use with the SDK

Install @pipeworx/sdk to call tools from any TypeScript/Node project.

TypeScript 
import { Pipeworx } from '@pipeworx/sdk';
const px = new Pipeworx();
const result = await px.call("get_oa", {});
ask_pipeworx 
// Or ask in plain English:
const answer = await px.ask("find free legal copies of paywalled papers by doi");