io.github.cyanheads/crossref-mcp-server

Resolves a Crossref member ID to its publisher/organization record: primary name, alternate imprint names, owned DOI prefixes, registered DOI counts, a per-work-type breakdown, and per-category metadata deposit coverage. Members are the organizations that register DOIs with Crossref, so this answers "what does this publisher publish, and how completely do they deposit metadata?" The member that holds a DOI now is the memberId crossref_get_work or crossref_search_works returns for it — pass that ID here. crossref_get_prefix returns the member a DOI prefix record names, the prefix's registrant, which for a transferred title is a former publisher rather than the DOI's current one.

Resolves a DOI prefix — the registrant portion of a DOI, e.g. "10.1038" — to the Crossref member its prefix record names: the publisher name and numeric member ID. That member is the prefix's registrant, so for a title transferred to another publisher it is not the member holding the DOI now — crossref_get_work's memberId names that one. The Crossref prefix record carries only these three facts (no counts, coverage, or flags); the returned memberId chains directly into crossref_get_member for the full publisher record.

Returns the outgoing reference list for a DOI — the works cited by this paper. Each reference includes the deposited citation string and, where Crossref has resolved it, a DOI you can look up with crossref_get_work. Results are paged: referenceCount is the full deposited total, and when more remain the response carries a nextOffset to pass back as offset. Reference list coverage varies by publisher; many older works and non-participating publishers have no indexed references. Incoming citations — the works that cite this paper — are not available through Crossref; use OpenAlex for that.

Resolves a DOI to its full Crossref metadata record: title, authors, editors, affiliations, abstract (when deposited), journal or container with the volume, issue, pages, and article number that locate the work in it, ISSNs and ISBNs, publication date, type, license, full-text links, and funder acknowledgements. The author list is paged: authorCount is the full deposited total, offset and limit select the page (25 authors by default), and when authors remain the response carries a nextOffset to pass back as offset — large-collaboration papers deposit thousands. Post-publication updates are relayed as Crossref records them: updatedBy names each correction, retraction, expression of concern, or new version issued against this work, with its notice DOI and whether the publisher or Retraction Watch recorded it, and updateTo names the works this record is itself a notice for. An absent updatedBy does not mean the work was never updated — coverage depends on those deposits. relations lists related identifiers, such as a preprint and its published version, grouped by relation type; only the Crossref-registered DOIs among them resolve through crossref_get_work. memberId is the Crossref member that holds the DOI now — pass it to crossref_get_member for the publisher record and its deposit coverage; the prefix of the DOI names the member that registered the prefix, which for a transferred title is a former publisher. Outgoing references are reported as a count in referencesCount; the reference entries themselves come from crossref_get_references. The isReferencedByCount field reports the total incoming citation count from Crossref; the citing works themselves are not available through Crossref — use OpenAlex for citation graphs.

Finds funders registered in the Crossref Funder Registry by name or funder DOI. Provide funder_doi for an exact single-funder lookup — the full DOI ("10.13039/100000001"), the bare registry ID ("100000001"), or either behind a doi: or https://doi.org/ prefix — or query for name-based search. Name-query results page with offset — the nextOffset enrichment carries the value for the following page, up to offset + rows = 100000. Set include_works to true to also return a page of the most recent works funded by the matched funder; that list pages two ways, in two orders. works_offset is the simple one: newest published first, capped ten times lower at works_offset + rows = 10000. works_cursor has no ceiling and reaches the whole funded-works list, newest registered first — ordered by the date each DOI was registered with Crossref, since Crossref does not walk a publication-date sort by cursor: pass works_cursor="*" on the first call, then chain the nextWorksCursor token from each response. The two cannot be combined, and a cursor walk always starts at the most recently registered work — it cannot resume from an offset. This list also counts works funded by the funder's registry descendants, which a crossref_search_works filter on {"funder": "10.13039/<id>"} does not; a funder_doi lookup returns those descendants' registry IDs as descendants, and the funder's own ID OR'd with each of them in the funder filter ({"funder": "<id>,funder:<descendant>,…"}) counts the same scope with date, type, or other filters. Returns funder name, registry ID, country, and alternate names, plus the work count of the ID alone on a funder_doi lookup. The Funder Registry supersedes entries, and a deprecated one answers to the same names as its successor while carrying only a fraction of its works: such a record carries replacedBy with the superseding registry ID and the response carries a notice naming it. The replacement is never followed automatically — re-run with funder_doi set to that ID to get the current entry.

Finds Crossref journal records by ISSN or title query. Provide issn for an exact single-journal lookup, or query for title-based search returning up to rows results. Title-query results page with offset — the nextOffset enrichment carries the value for the following page, up to offset + rows = 100000. Set include_works to true to also return a page of the matched journal's most recent works — the works deposited under any of its ISSNs, whichever one you passed; that list pages two ways, in two orders. works_offset is the simple one: newest published first, capped ten times lower at works_offset + rows = 10000. works_cursor has no ceiling and reaches the whole works list, newest registered first — ordered by the date each DOI was registered with Crossref, since Crossref does not walk a publication-date sort by cursor: pass works_cursor="*" on the first call, then chain the nextWorksCursor token from each response. The two cannot be combined, and a cursor walk always starts at the most recently registered work — it cannot resume from an offset. Returns journal metadata: title, publisher, ISSNs with their print or electronic form, subject areas, DOI counts (total, current, backfile), and per-category metadata deposit coverage — how completely the journal deposits abstracts, references, ORCIDs, funders, licenses, and similar metadata. An issn lookup also returns DOI counts by issued year.

Searches the Crossref works index (~188M records) by free text and/or structured filters. The generic query matches loosely across all fields; scope precisely with the field-specific parameters queryTitle, queryAuthor, and queryContainerTitle, or resolve a known citation to its DOI with queryBibliographic — all combine with each other and with query. Use the filter parameter for structured filtering (object with hyphen-separated Crossref keys). Sort options: relevance, score, is-referenced-by-count, published, deposited, indexed, created. Each work returns at most authorLimit authors (25 by default) with authorCount reporting the full deposited total, since a single page of large-collaboration papers can carry tens of thousands of author entries; crossref_get_work pages the whole author list for any DOI whose list was cut. Post-publication updates ride each work as Crossref records them: updatedBy names each correction, retraction, expression of concern, or new version issued against it, and updateTo the works it is itself a notice for — an absent updatedBy does not mean the work was never updated. Offset-based paging is capped at ~10K results; use cursor="*" to start cursor-based deep paging, then pass the nextCursor value from each response to continue. A walk with a query term and no sort runs by relevance, one with filters only in Crossref registration order. The walk ends on the page where nextCursor is absent — that page also carries a notice saying the list is exhausted. Cursor and offset cannot be combined.