citeguard MCP server

citeguard is a small helper that checks whether the papers you are about to cite have been retracted, corrected, or flagged with an expression of concern. It looks each one up in Crossref, a free public database of research records. It is handy for anyone writing a paper, a summary, or a review who wants to avoid quoting work that has been pulled.

What this MCP server does

You give your AI a citation, usually as a DOI (the paper's permanent ID number) or a list of them in a file. Your AI passes it to citeguard, which asks Crossref about that paper. citeguard looks for three signals: a publisher note saying the paper was updated, a note saying it was updated by something else (often a retraction), and a title that starts with words like RETRACTED or WITHDRAWN. It then tells you what it found and how serious it is, so you can decide whether to keep the citation.

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What you can do with it

• Check a single DOI for retraction, correction, or concern
• Check a whole bibliography file at once
• Get a clear severity for each citation (retracted, concern, corrected, or clean)
• Spot older papers that only show a RETRACTED or WITHDRAWN title prefix
• Use it inside a writing or research workflow without leaving your chat
• Reuse cached results so you are not hammering the free Crossref service

Try asking your AI

• “Check this DOI for me: 10.1016/S0140-6736(97)11096-0”
• “Look through references.bib and tell me which entries are retracted”
• “Is 10.1016/S0140-6736(20)31180-6 still safe to cite?”
• “Go through these five DOIs and flag anything with an expression of concern”

What it gives back to you

You get back a short answer per citation: the paper's title, its DOI, and a status such as retracted, concern, corrected, or clean. For a file, you get a list of every entry with its status, so you can scan it quickly. If nothing is found, it says so plainly, which means no known signal was found, not a guarantee. The chat shows this as a simple list or table you can read at a glance.

Before you start

Who it's for

Researchers, students, editors, and anyone writing a paper, summary, or review who wants to avoid citing retracted work.