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Verification records what our published tests found on a specific version at a specific date. It is not a warranty, and it does not certify that software is free of defects.

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Catalogue/MCP servers/Crossref MCP Server

Crossref MCP Server

cyanheads · MCP server

Gives your AI assistant the Crossref REST API for scholarly metadata, through seven tools. It resolves a DOI to its full record with authors, abstract, licence, funders and post-publication updates, searches works by free text or structured filters, returns the reference list a paper cites, and looks up journals by ISSN or title, funders and publisher members. It can run as a local process or be used through a public hosted endpoint.

Written by ooruby from the README of @cyanheads/crossref-mcp-server 0.4.2.

Not claimed by its maker. Is this yours? Prove it and answer the findings

Why it's useful

Your agent can look up the Crossref record behind a citation, including its references, funders and publisher.

What you could do with it

  1. 1Resolve a DOI to its title, authors, journal, licence and funders.
  2. 2Search scholarly works by title and author, filtered by publication date and work type.
  3. 3Check a DOI for recorded corrections, retractions and new versions before citing it.

Written from its documentation: what it says it can do, not what our checks found.

CRMCP serverResearch

Maintenance

Not measured

No release date is on record for this package yet. The nightly publisher check records one as it reaches each npm package, about once every ten nights.

Release activity only: it says nothing about quality or safety, and a finished small package can be fine without releases. How it is measured

Not yet tested

What this does not cover

  • ·Everything. Treat it as you would software from anywhere else.

Receipt history: every signed receipt for every version of this listing, and what changed between them.

In its maker's words

Resolve DOIs, search ~155M scholarly works, fetch references, and look up publishers via the Crossref REST API. STDIO or Streamable HTTP.

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How far this has been checked

Static scanned

What it establishes
Its published package, or for a hosted server its source repository at a recorded commit, was read file by file, without running it, by every check in our current scan.
What it does not
How it behaves when it runs, or anything the scan does not read yet: several rubric checks, the repository's history, and compiled code in folders named dist or build. For a hosted server, that the endpoint runs the code that was read. The ooruby Index sets out exactly what was read.
Exactly what was read
Version 0.4.2, the file with digest sha512-7SWgsLFXqgEuJ6nwk3YtqiiZeORxbFGkqTSdvrhN2+dbbvJd8mpH/bmW5smDDBd1ic3u4g5Ji9JP9PhifG1C1g==, as the registry publishes it. A published version cannot be replaced, so this names the same bytes for anyone who checks.
Authentication
No auth declared. Its hosted endpoint, as the official MCP registry lists it, does not say it asks for a key. That is what the listing declares, not a finding that it has no protection.
How the rungs work

Adding it

Paste this into your client's MCP configuration.

{
  "mcpServers": {
    "crossref-mcp-server": {
      "command": "npx",
      "args": [
        "-y",
        "@cyanheads/crossref-mcp-server@0.4.2"
      ]
    }
  }
}

Or run it directly.

npx -y @cyanheads/crossref-mcp-server@0.4.2

Pinned to 0.4.2, which is the version the findings above were found in. Drop the version to take whatever is newest, and the report on this page stops describing what you installed.

Where this came from

Registry
npm
Package
@cyanheads/crossref-mcp-server
Version read
0.4.2
Resolved
2026-10-10
Open the source(opens in a new tab)

No build provenance published. The repository above is the one the publisher declared, and nothing links it to the package you would install. That is not a mark against this listing, since most packages are published this way, but it is a check nobody can run.

The badge, if this is your listing

It renders the current rung (static scanned) and links back here, where what that does and does not establish is one click away. It updates itself as the evidence deepens.

[![ooruby: static scanned](https://ooruby.com/api/badge/cyanheads-crossref-mcp-server)](https://ooruby.com/market/cyanheads-crossref-mcp-server)

About this listing

Kind
MCP server
Category
Research
Pricing
Free
Sandbox
No
Hosted
No
Updated
2026-10-08
Price
Free
Get it freeVisit maker
Rating
no reviews yet
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Verification records what our published tests found on a specific version at a specific date. It is not a warranty, and it does not certify that software is free of defects.