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Unpaywall

Unpaywall MCP for AI. Find free PDFs using only a DOI.

Claude Claude
ChatGPT ChatGPT
Cursor Cursor
Gemini Gemini
Windsurf Windsurf
VS Code VS Code
JetBrains JetBrains
Vercel Vercel
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Unpaywall (Open Access Papers) MCP on Cursor AI Code EditorUnpaywall (Open Access Papers) MCP on Claude Desktop AppUnpaywall (Open Access Papers) MCP on OpenAI Agents SDKUnpaywall (Open Access Papers) MCP on Visual Studio CodeUnpaywall (Open Access Papers) MCP on GitHub Copilot AI AgentUnpaywall (Open Access Papers) MCP on Google Gemini AIUnpaywall (Open Access Papers) MCP on Lovable AI DevelopmentUnpaywall (Open Access Papers) MCP on Mistral AI AgentsUnpaywall (Open Access Papers) MCP on Amazon AWS Bedrock

Connect to your AI in seconds.

Unpaywall MCP Server checks scholarly articles for open access status using a DOI. You enter a Digital Object Identifier (DOI), and it tells you if a journal paper, even one behind a paywall, has a legally available PDF link somewhere else online.

It instantly confirms the Open Access status of research papers without needing to navigate multiple university libraries.

What your AI can do

Get article oa status

Checks an article's DOI to report its Open Access status and potential download links.

Confirm Article Accessibility

Checks a provided DOI to determine if the scholarly article has an open-access license.

Retrieve Direct PDF Links

Pulls direct, legal download links for the full-text research paper from known repositories.

Identify Open Access Type

Reports metadata detailing the type of open access available (like green or gold).

Automate Source Finding

Allows your agent to process multiple DOIs and find accessible versions for literature reviews.

Included with Plan

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AI Agent

Unpaywall (Open Access Papers) MCP Server: 1 Tool

The `get_article_oa_status` tool checks any article's DOI to report its Open Access status and find direct PDF links.

Make your AI actually useful.

Add this MCP to Claude, Cursor, or Windsurf and your AI stops guessing. It gets real tools to look things up, take action, and handle the stuff you keep doing by hand.

Start using Unpaywall (Open Access Papers) on Vinkius

Get Article Oa Status

Checks an article's DOI to report its Open Access status and potential download links.

Security and governance baked right in.

Pick your AI client below to get set up. Just create a Vinkius account, subscribe, and you're instantly up and running. We handle the entire backend infrastructure, delivering out-of-the-box support for HTTPS Streamable, SSE, and OAuth2—zero messy routing required.

Claude AI

Claude AI

1

Open Claude Settings

Go to claude.ai, click your profile icon, then navigate to Customize → Connectors.

2

Add Custom Connector

Click the "+" button and select Add custom connector. Paste your Vinkius endpoint URL:

https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp

Replace [YOUR_TOKEN_HERE] with your token from cloud.vinkius.com. For OAuth-protected servers, expand Advanced settings to add credentials.

3

Start a conversation

Open a new chat. The Unpaywall integration is available immediately — no restart needed.

Choose How to Get Started

Build a custom MCP for your own tools, or connect a ready-made integration from our catalog.

Build Your Own

Turn any API into an MCP. Import a spec, define Agent Skills, or deploy with MCPFusion.

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Start building

Make Your AI Do More

Start with Unpaywall (Open Access Papers), then connect any of our 5,100+ other servers whenever your AI needs more. One click, no limits.

  • Use this MCP plus 5,100+ others, all in one place
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  • Works with Claude, ChatGPT, Cursor, and more
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Independent Platform Disclaimer: Vinkius is an independent platform and is not affiliated with, endorsed by, sponsored by, verified by, or otherwise authorized by Unpaywall. All third-party trademarks, logos, and brand names are the property of their respective owners. Their use on this website is strictly for informational purposes to identify service compatibility and interoperability.

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Works with Claude, ChatGPT, Cursor, and more

The Model Context Protocol standardizes how applications expose capabilities to LLMs. Instead of operating in isolation, your AI gains direct access to external platforms, live data, and real-world actions through secure, standardized connections.

This connection provides 1 powerful capabilities that interface natively with Claude, ChatGPT, Cursor, and other compatible AI platforms. No middleware. No custom integration required.

Finding free scholarly papers shouldn't feel like detective work.

Right now, finding a free article means starting with Google, then checking the publisher's site, potentially hitting an institutional login wall, and finally navigating to different repository pages. You end up copy-pasting DOIs into three separate systems just to verify if the paper is actually available for free.

With Unpaywall MCP Server, you feed the DOI directly into your agent using `get_article_oa_status`. The system handles all the checks and returns a simple answer: yes/no, along with the direct download link. It cuts out every manual click.

Unpaywall MCP Server: Know if a paper is free.

The tedious steps that vanish are the multi-system checks and the endless dead ends. You stop wasting time guessing if a DOI leads to a paywall or a public PDF, and you start working with verifiable sources.

This tool changes your research flow from 'hopeful searching' to 'verified retrieval.' It gives you certainty about your source material.

What your AI can actually do with this

You run into paywalls all the time when you're doing literature reviews. This server fixes that problem. Your agent connects to the get_article_oa_status tool and instantly confirms if any scholarly article is actually open access, regardless of what a publisher tries to charge for it.

The whole deal hinges on the Digital Object Identifier (DOI). You feed your client the DOI, and the server does all the heavy lifting. It doesn't just tell you 'yes' or 'no'; it gives you specific data points that let you bypass paywalled content entirely and get straight to the research.

When you use this tool, your agent first processes the article’s Open Access status. This check determines if a legally available open-access license exists for the work. It confirms the paper's accessibility before you waste time navigating university library portals or dealing with paywall pop-ups. Knowing the OA status upfront saves huge amounts of time.

The tool doesn't stop at just confirming eligibility; it retrieves direct, functional download links for the full text. These are legal PDF downloads sourced from known institutional repositories—not some sketchy file dump. You get a clean link that your agent can use immediately to pull the entire research paper. It pulls those direct links so you don't have to manually search through multiple archives.

Furthermore, it gives you metadata on the type of open access available. This means you’ll know if the article falls under green open access (a version uploaded by the author) or gold open access (published directly in an OA journal). That detail is crucial for tracking how research gets disseminated and helps your agent understand the paper's provenance.

When you need to process a whole list of papers—say, twenty DOIs from a conference proceedings—you can send multiple identifiers at once. The tool processes all those DOIs efficiently, finding accessible versions across the board so you don’t have to run the checks one by one. It automates the source-finding part of your literature review.

This isn't guesswork about whether a paper is open access; it's a technical confirmation using established identifiers and known repository sources. Your agent needs this tool when it's supposed to read an article, but you don't want it stalled out on a payment screen or redirected to a login page.

Built · Hosted · Managed by Vinkius Unpaywall-MCP Server - Check Open Access Papers by DOI
Server ID 019e3902-60f8-732b-ac88-025ea0ba1d37
Vinkius Inspector
Compliance Grade A+
Score 100/100
Vinkius Inspector Badge — Score 100/100

Questions you might have

Does Unpaywall (Open Access Papers) MCP Server work for any DOI? +

It works for any standard scholarly DOI. The tool is designed to check the global status of academic papers, not just those from one journal or university.

What if a paper isn't open access? Does get_article_oa_status tell me that? +

Yes. If the tool checks the DOI and cannot confirm an OA link, it reports that the article appears to be behind a publisher paywall.

Do I need to provide an email address to use get_article_oa_status? +

Yes. The server requires you to enter your email address during setup because Unpaywall's API policy mandates it for usage tracking.

Can this tool retrieve the full text if I only have an abstract? +

No, the tool needs a DOI. If you only have the abstract or title, first find the corresponding DOI before running get_article_oa_status.

What happens if I use `get_article_oa_status` with an invalid or malformed DOI? +

The tool returns a specific error message indicating the input was invalid. The system catches these errors, letting you know exactly what went wrong so your agent can correct the data.

Are there any rate limits when calling `get_article_oa_status`? +

Usage is subject to Unpaywall's underlying API policy. Vinkius manages quota allocation, and excessive requests will result in a clear rate limit error that your agent can handle.

Does `get_article_oa_status` provide metadata beyond just the PDF link? +

Yes, it provides detailed information about the Open Access status. You get data specifying the type of OA (like green or gold) and the source repository.

Which AI clients are compatible with using `get_article_oa_status`? +

Since this is an MCP Server on Vinkius, it works with any client that supports the Model Context Protocol. This includes Claude, Cursor, VS Code, and other compatible agents.

How do I check if a specific research paper is available for free? +

Use the get_article_oa_status tool with the paper's DOI. Your agent will query the Unpaywall database and return the Open Access status along with direct links to the PDF if available.

Does this tool provide legal versions of the papers? +

Yes. Unpaywall only indexes legal, author-archived, or publisher-provided Open Access versions of scholarly articles. It does not access pirated content.

What information is required to use this server? +

You need the DOI (Digital Object Identifier) of the article and a valid email address to authenticate with the Unpaywall API.

Built & Managed by Vinkius 30s setup 1 tools

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All 1 tools are live and waiting. You're up and running in seconds.

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