Citation Checker
Check references and DOIs
Paste a bibliography or a single reference and find out whether the papers are real. Ask "are these references real?", "check my bibliography", "verify this citation", "is this DOI correct?" or "has this paper been retracted?". Citation Checker looks every reference up in Crossref, the DOI system (doi.org) and OpenAlex, which index the scholarly record, and gives each one a clear verdict: found, mismatch or not found. A mismatch means a real paper exists but the reference gets something wrong, such as a DOI that belongs to another paper or a wrong year or author list; the real record is shown so the error is easy to fix. Not found means nothing matching exists, which for a bibliography entry often points to an invented or garbled citation. It also reports whether a paper has been retracted, partially retracted, flagged with an expression of concern or corrected, from the notices that publishers and the Retraction Watch database register with Crossref. It checks up to 10 references at a time. It compares bibliographic details only (title, authors, year, journal, DOI); it does not read papers or judge whether their claims are true. Books, reports, web pages and talks are often missing from the scholarly indexes, so a not found there is a prompt to check by hand, not proof. It stores nothing about you: answers are cached for up to six hours, and the only lasting record is a daily count of calls per tool.
What you can ask
- Check my bibliography and tell me which references are real
Example path
MCP connector
- Server URL
https://citations.openkrill.app/mcp- Login
- None
- Protocol
- MCP 2026-07-28
- Instructions
Citation Checker: Check references and DOIs. Use when the user wants references, a bibliography, a citation or a DOI checked, or asks whether a paper was retracted. Send each reference as one string as the user wrote it, up to 10 per call; split longer lists into several calls. Report the verdict for every reference. found: a real record matches. mismatch: a real record exists but differences (doi, title, authors, year) say what the reference gets wrong, so show the real record's DOI, title, authors and year. not_found: nothing matches in Crossref or OpenAlex; say it may be invented or garbled, and that books, reports and web pages are often not indexed. unavailable: the lookup failed, suggest trying again. Always state a retraction.status of retracted, partially_retracted, expression_of_concern or corrected, with the notice dates; none_recorded means the source lists no notice, and not_checked means the source carries no retraction data. A year-only mismatch can come from a preprint or a later edition having another year. This checks bibliographic details only; do not claim it verified what a paper says. This server allows 60 tool calls a minute per network and 5,000 a day for all callers together; the day count resets at 00:00 UTC. If a tool fails, gives a wrong answer, or a tool you need is missing, call with one short message (kind, message, tool); reads the answer.
Tools
Reads data2
Changes data1
Skills
None in the store listings or on the server