Tools

11 tools for working with PubMed, PubMed Central, and Europe PMC data:

pubmed_search_articles

Search PubMed with full NCBI query syntax and filters.

• Free-text queries with PubMed's full boolean and field-tag syntax
• Field-specific filters: author, journal, MeSH terms, language, species
• Common filters: has abstract, free full text
• Date range filtering by publication, modification, or Entrez date
• Publication type filtering (Review, Clinical Trial, Meta-Analysis, etc.)
• Sort by relevance, publication date, author, or journal
• Pagination via offset for paging through large result sets
• Optional brief summaries for top N results via ESummary
• Returns the original query plus the fully applied PubMed query and normalized filter metadata

pubmed_fetch_articles

Fetch full article metadata by PubMed IDs.

• Batch fetch up to 200 articles at once (auto-switches to POST for batches >= 100)
• Returns structured data: title, abstract, authors with deduplicated affiliations, journal info, DOI
• Direct links to PubMed and PubMed Central (when available)
• Optional MeSH terms, grant information, and publication types
• Handles PubMed's inconsistent XML (structured abstracts, missing fields, varying date formats)

pubmed_fetch_fulltext

Fetch full-text articles via a three-stage chain: NCBI PMC EFetch → Europe PMC fullTextXML → Unpaywall.

• Accepts exactly one of pmcids (direct PMC IDs), pmids (PubMed IDs, auto-resolved), or dois (auto-resolved to PMC via the ID Converter; preprints and EPMC-only OA fall through to Europe PMC / Unpaywall)
• NCBI PMC and Europe PMC both return structured JATS; output records origin via viaSource: "pmc" | "europepmc" | "unpaywall"
• Europe PMC layer (enabled by default; disable with EUROPEPMC_ENABLED=false) recovers PMC-counterpart records that NCBI PMC EFetch missed, and resolves DOI input to PMC counterparts when one exists. EPMC's fullTextXML is PMC-keyed, so preprints (PPR), patents (PAT), and Agricola (AGR) are reachable via pubmed_europepmc_search for metadata but have no full text via this chain.
• Unpaywall layer (enabled by setting UNPAYWALL_EMAIL) resolves DOIs to legal OA copies; extracts HTML landing pages to Markdown via Defuddle or PDFs to text via unpdf
• Discriminated output contract — source: "pmc" (structured sections, regardless of whether it came from PMC or EPMC) or source: "unpaywall" (best-effort body + contentFormat: html-markdown or pdf-text)
• Structured unavailable reasons (not-found, no-pmc-fallback-disabled, no-epmc-fulltext, no-doi, no-oa, fetch-failed, parse-failed, service-error) so callers can retry or explain to users without parsing text
• Each unavailable entry carries idType (pmid / pmcid / doi) and triedTiers — per-tier outcomes (not-attempted, miss, no-fulltext, service-error, …) in execution order, so callers can see which stage failed and why
• Section filtering by title (case-insensitive match, e.g. ["methods", "results"]) and configurable max sections apply to PMC output
• Character budgets keep context size predictable: maxCharacters caps body text per article (PMC sections and subsections, or the Unpaywall body), maxCharactersPerSection caps a single PMC section, and overflowMode picks between truncate (fill sections in document order) and outline (split the budget evenly so every heading survives with an excerpt). Budgets run after the semantic filters, and a truncation object reports per-article and per-section character counts whenever anything was shortened
• Up to 10 articles per request

pubmed_europepmc_search

Search Europe PMC (EBI/EMBL-EBI), a broader open-access biomedical corpus than PubMed alone.

• Surfaces records PubMed search can't reach — preprints (source: PPR), patents (source: PAT), Agricola (source: AGR), plus everything in PubMed (MED) and PMC (PMC). On recent queries this can mean dozens of relevant hits with zero PubMed overlap.
• Default sources ["MED", "PMC", "PPR"]; pass sources to include PAT / AGR
• Cursor-based pagination via cursorMark (unlike pubmed_search_articles, which uses offset) — * for the first page, return nextCursorMark for the next
• Output discriminator on source plus optional pmid / pmcId / doi cross-walking
• abstractSnippet is capped at 400 characters to keep a page bounded; abstractTruncated says whether it was cut, and pubmed_europepmc_fetch returns the whole abstract for the records worth reading in full
• Disabled when EUROPEPMC_ENABLED=false; tool is not registered in that case

pubmed_europepmc_fetch

Fetch complete Europe PMC records by source + epmcId, the detail counterpart to pubmed_europepmc_search.

• Returns the full, untruncated abstract as display-ready plain text — markup stripped, HTML entities decoded
• Addressed by the source and epmcId of a search hit, the only identifier preprint (PPR), patent (PAT), and Agricola (AGR) records reliably carry — pubmed_fetch_articles needs a PMID and pubmed_fetch_fulltext needs a PMCID, PMID, or DOI
• Up to 25 records per call, resolved in a single Europe PMC request
• Pairs unresolved requests back to the caller in notFound instead of failing the batch
• Disabled when EUROPEPMC_ENABLED=false; tool is not registered in that case

pubmed_format_citations

Generate formatted citations for articles.

• Five citation styles: APA 7th, MLA 9th, BibTeX, RIS, Vancouver (ICMJE/NLM)
• Request multiple styles per article in a single call
• Hand-rolled formatters — zero external dependencies, fully Workers-compatible
• Up to 50 articles per request
• Reports formatted counts and unavailable PMIDs for partial-result handling

pubmed_find_related

Find articles related to a source article via ELink.

• Three relationship types: similar (content similarity), cited_by, references
• Results enriched with title, authors, publication date, and source via ESummary
• Results returned in NCBI's relevance order

pubmed_spell_check

Spell-check a biomedical query using NCBI's ESpell.