CiteStamp

CiteStamp MCP server

Ground citations before your agent emits them.

CiteStamp is a free citation-health tool for researchers: it checks references against the public scholarly registries (Crossref, DataCite, OpenAlex) and flags the ones that do not resolve to a known work or that a publisher has marked retracted, the hallucinated-citation failure mode LLM users keep hitting.

This repo is the install guide for the hosted MCP server over CiteStamp's CC0 citation graph. There is nothing to build or run locally; the server is remote.

Endpoint	https://mcp.citestamp.com/mcp
Transport	streamable-http
Protocol	2025-06-18
Auth	None. Anonymous at 10 requests/min per IP. An optional free key (email [email protected]) raises that to 60/min; Pro to 600/min
Data	CC0 citation graph; human-signed and machine-inferred claims kept strictly apart

The tools (all read-only)

• what_supports / what_refutes: typed edges bearing on a claim
• what_cites / references_of: the citing and cited works around a reference
• edges_about: edges on a topic
• retraction_listing: whether the Retraction Watch database lists a DOI as retracted, from the dated export CiteStamp joins weekly. Not listed means not in that export; it does not check the publisher record
• check_reference: whether a reference resolves to a real work, before an answer cites it. Give a DOI, an arXiv id or the reference as written. It reads Crossref, DataCite and doi.org (which answers for every DOI agency) and says found, confirm (with the reason), not found in the named sources on a date, or couldn't check. A not-found is not proof that a work was never published

Every result carries its tier: accountable edges are signed by a human identity (ORCID); inferred edges are machine-derived. Your agent can ask for signed-only.

Add it to your client

No key is needed. Every snippet below works as written.

Gemini CLI (extension)

gemini extensions install https://github.com/citestamp/mcp

Or add the server by hand in ~/.gemini/settings.json:

{ "mcpServers": { "citestamp": { "httpUrl": "https://mcp.citestamp.com/mcp" } } }

Gemini Spark (custom app)

In the Gemini web app: Settings & help → Connected Apps → under "Custom apps for Spark" click Add a custom app → enter https://mcp.citestamp.com/mcp → Next. Type @ in a prompt and pick CiteStamp to make Gemini use it. Custom apps need access to Gemini Spark on a personal Google Account with Keep Activity on.

Claude (claude.ai / Desktop)

Settings → Connectors → Add custom connector → URL https://mcp.citestamp.com/mcp. Leave authentication empty.

Claude Code

claude mcp add --transport http citestamp https://mcp.citestamp.com/mcp

Cursor (~/.cursor/mcp.json)

{ "mcpServers": { "citestamp": { "url": "https://mcp.citestamp.com/mcp" } } }

Cline (MCP settings)

{ "mcpServers": { "citestamp": {
    "type": "streamableHttp",
    "url": "https://mcp.citestamp.com/mcp" } } }

VS Code (.vscode/mcp.json)

{ "servers": { "citestamp": {
    "type": "http",
    "url": "https://mcp.citestamp.com/mcp" } } }

If a snippet drifts from your client's current config schema, your client's MCP docs win; the endpoint is the stable part.

Optional: raise the rate limit

A key is never required. If you hold one, send it as a header on the same endpoint:

Authorization: Bearer <your key>

For Claude Code that is --header "Authorization: Bearer <your key>"; for the JSON configs, add "headers": { "Authorization": "Bearer <your key>" } to the server entry. A bad key is a loud 401, never a silent downgrade to anonymous, so add the header only once you have a key.

What this is not

CiteStamp reports what public registries say at a dated point in time. It does not judge the truth or quality of any work. check_reference answers found, confirm (with the reason), not found in the named sources on a date, or couldn't check; a not-found is not proof a work was never published. retraction_listing says whether the dated Retraction Watch export lists a DOI, and does not check the publisher record. Statements about works, never about people.

Links

• Integration guide + REST API: https://citestamp.com/for-ai
• Check a bibliography in the browser (free, nothing uploaded): https://citestamp.com/check
• Reference-health badge for any DOI: https://citestamp.com/citestamped/
• Privacy: https://citestamp.com/privacy · Contact: [email protected]

CiteStamp is built by 3Rivers Enterprises LLC, Fort Wayne, Indiana.