crossref-mcp-server

Previous value: -"Abstract when deposited by the publisher. Many records lack abstracts. Publishers deposit it as JATS XML, so this is the text of that deposit with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first."New value: +"Abstract when deposited by the publisher. Many records lack abstracts. Publishers deposit it as JATS XML, so this is the text of that deposit with markup removed and character references decoded; numeric JATS superscripts retain caret notation (10^{16}, GeV^2), a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first."

Added value: +{
+  "description": "License start date-time as deposited by the publisher",
+  "type": "string"
+}

Added value: +{
+  "description": "Content version of the linked manuscript as deposited (e.g. vor, am)",
+  "type": "string"
+}

Previous value: -"Abstract when present in the indexed record — the text of the publisher’s JATS deposit, with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first"New value: +"Abstract when present in the indexed record — the text of the publisher’s JATS deposit, with markup removed and character references decoded; numeric JATS superscripts retain caret notation (10^{16}, GeV^2), a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first"

Previous value: -"Maximum number of references to return in one page (1–500, default 100). Most works fit in a single page; bibliography records can carry tens of thousands."New value: +"Maximum number of references to return in one page (1–500 per call, default 100). A larger value, up to 100000, returns 500 and says so in notice; nextOffset continues after the references returned. Most works fit in a single page; bibliography records can carry tens of thousands."

Previous value: -500New value: +100000

Previous value: -"Coverage guidance when no references are indexed, or a range explanation when the requested offset is past the end of the list. Absent on a normal page."New value: +"Coverage guidance when no references are indexed, a range explanation when the requested offset is past the end of the list, or which references this page covers and the offset that reaches the next ones. Leads with the value requested and the cap applied when limit was above its per-call cap. Absent on a page that holds the whole list with limit within its cap."

Added value: +{
+  "description": "Who supplied the DOI: \"publisher\" when the citing work's publisher deposited it, \"crossref\" when Crossref matched the citation to it.",
+  "type": "string"
+}

Added value: +{
+  "description": "Edition of the cited book, as deposited",
+  "type": "string"
+}

Added value: +{
+  "description": "Issue",
+  "type": "string"
+}

Added value: +{
+  "description": "Title of the series the cited work belongs to, with inline formatting markup removed",
+  "type": "string"
+}

Added value: +{
+  "description": "Title of the cited book or proceedings volume, with inline formatting markup removed. The only title on many book and chapter citations.",
+  "type": "string"
+}

Previous value: -"Maximum number of authors to return in one page (1–500, default 25). Ordinary records fit in a single page; large-collaboration papers in particle physics and genomics deposit thousands."New value: +"Maximum number of authors to return in one page (1–500 per call, default 25). A larger value, up to 100000, returns 500 and says so in notice; nextOffset continues after the authors returned. Ordinary records fit in a single page; large-collaboration papers in particle physics and genomics deposit thousands."

Previous value: -500New value: +100000

Previous value: -"When updatedBy is present, the update types Crossref records for this work with the source of each, and where the notice is read. Then which authors this page covers and the offset that reaches the next ones, or an explanation when the requested offset is past the end of the author list. Both share this one string when both apply. Absent when the page holds the whole author list and no update is recorded."New value: +"When updatedBy is present, the update types Crossref records for this work with the source of each, and where the notice is read. Then, when limit was above its per-call cap, the value requested and the cap applied. Then which authors this page covers and the offset that reaches the next ones, or an explanation when the requested offset is past the end of the author list. All share this one string when more than one applies. Absent when the page holds the whole author list, no update is recorded, and limit was within its cap."

Previous value: -"Maximum funders to return for name queries, or works when include_works is true (1–100, default 10)"New value: +"Maximum funders to return for name queries, or works when include_works is true (1–100 per call, default 10). A larger value, up to 1000, returns 100 and says so in notice; nextOffset and nextWorksOffset continue after the records returned."

Previous value: -100New value: +1000

Previous value: -"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, a returned funder that the Funder Registry has deprecated in favor of another entry, or a query or funder_doi supplied blank with nothing else to search by, so the page lists every funder unfiltered. Absent otherwise. A page needing more than one caveat carries them all in this one string."New value: +"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved (naming the offset and smaller rows that reach the last records below the ceiling, when any remain), a returned funder that the Funder Registry has deprecated in favor of another entry, a query or funder_doi supplied blank with nothing else to search by, so the page lists every funder unfiltered, or a rows value above its per-call cap, naming the value requested and the cap applied. Absent otherwise. A page needing more than one caveat carries them all in this one string."

Previous value: -"Maximum number of journals to return for title queries, or works when include_works is true (1–100, default 10)"New value: +"Maximum number of journals to return for title queries, or works when include_works is true (1–100 per call, default 10). A larger value, up to 1000, returns 100 and says so in notice; nextOffset and nextWorksOffset continue after the records returned."

Previous value: -100New value: +1000

Added value: +{
+  "description": "DOIs issued before the current window",
+  "type": "number"
+}

Added value: +{
+  "description": "Per-category metadata deposit coverage for this journal — each a 0–1 fraction split into current and backfile DOIs. Signals how completely the journal deposits abstracts, references, ORCIDs, funders, licenses, and similar metadata. A window with no DOIs reports every fraction as 0, so read each fraction beside currentDois and backfileDois.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Metadata deposit coverage for one category",
+    "properties": {
+      "backfile": {
+        "description": "Coverage fraction (0–1) among backfile (older) DOIs",
+        "type": "number"
+      },
+      "category": {
+        "description": "Metadata deposit category, e.g. \"references\", \"abstracts\", \"orcids\", \"funders\", \"licenses\", \"affiliations\"",
+        "type": "string"
+      },
+      "current": {
+        "description": "Coverage fraction (0–1) among current (recent) DOIs",
+        "type": "number"
+      }
+    },
+    "required": [
+      "category"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "DOIs issued in the current window — this year and the two before it",
+  "type": "number"
+}

Added value: +{
+  "description": "Registered DOIs per issued year, ascending by year; a year with no DOIs has no entry. Returned on an issn lookup only — title-query results omit it.",
+  "items": {
+    "additionalProperties": false,
+    "description": "DOI count for one issued year",
+    "properties": {
+      "count": {
+        "description": "DOIs issued that year",
+        "type": "number"
+      },
+      "year": {
+        "description": "Issued year",
+        "type": "number"
+      }
+    },
+    "required": [
+      "year",
+      "count"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Previous value: -"Linking ISSN (ISSN-L). Absent when the journal has no linking ISSN registered — Crossref reports that as an explicit null rather than an omitted key."New value: +"Linking ISSN (ISSN-L). Crossref journal records do not carry one, so this is normally absent; issnTypes says which ISSN is print and which electronic."

Added value: +{
+  "description": "Each ISSN with its form — print or electronic",
+  "items": {
+    "additionalProperties": false,
+    "description": "One ISSN and its form",
+    "properties": {
+      "type": {
+        "description": "ISSN form, e.g. \"print\" or \"electronic\". Absent when Crossref records no form for this ISSN.",
+        "type": "string"
+      },
+      "value": {
+        "description": "ISSN",
+        "type": "string"
+      }
+    },
+    "required": [
+      "value"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Previous value: -"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, an include_works request that was skipped because the matched journal has no registered ISSN to address its works list by, or a query or issn supplied blank with nothing else to search by, so the page lists every journal unfiltered. Absent otherwise. A page needing more than one caveat carries them all in this one string."New value: +"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved (naming the offset and smaller rows that reach the last records below the ceiling, when any remain), an include_works request that was skipped because the matched journal has no registered ISSN to address its works list by, a query or issn supplied blank with nothing else to search by, so the page lists every journal unfiltered, or a rows value above its per-call cap, naming the value requested and the cap applied. Absent otherwise. A page needing more than one caveat carries them all in this one string."

Previous value: -"Maximum number of authors to return per work (1–500, default 25). Ordinary records fit under the default; large-collaboration papers deposit thousands, and a page of them is large enough to exhaust a client context. Each work reports its full deposited total as authorCount — call crossref_get_work with that work doi to page the authors this cap left out."New value: +"Maximum number of authors to return per work (1–500 per call, default 25; a larger value, up to 100000, applies 500 and says so in notice). Ordinary records fit under the default; large-collaboration papers deposit thousands, and a page of them is large enough to exhaust a client context. Each work reports its full deposited total as authorCount — call crossref_get_work with that work doi to page the authors this cap left out."

Previous value: -500New value: +100000

Previous value: -"Cursor token for deep paging. Pass \"*\" to start cursor-based paging (required past ~10K results), then pass the nextCursor value from each response until a response omits it, which means the list is exhausted. Cannot be combined with offset, or with a publication-date sort (published, published-print, published-online), which Crossref does not walk by cursor."New value: +"Cursor token for deep paging. Pass \"*\" to start cursor-based paging (required past ~10K results), then pass the nextCursor value from each response until a response omits it, which means the list is exhausted. A walk with a query term runs by relevance unless sort is set; a walk with filters only runs in Crossref registration order. Relevance scores shift slightly between identical requests, so a relevance walk can repeat or skip a record at a page boundary — sort:\"created\" walks every match without repeats. Cannot be combined with offset, or with a publication-date sort (published, published-print, published-online), which Crossref does not walk by cursor."

Previous value: -"Fields to return (reduces payload). Names are case-sensitive, and each fills one output field: DOI → doi, title → title, type → type, author → authors and authorCount, published / published-print / published-online → published, container-title → containerTitle, publisher → publisher, is-referenced-by-count → isReferencedByCount, score → score, abstract → abstract, volume → volume, issue → issue, page → page, article-number → articleNumber, ISSN → issn. A selected field absent from a work means the record does not deposit it. DOI is always returned whether or not it is listed here, so every result stays resolvable by crossref_get_work, which also returns the fields this list does not cover (license, funder, references, and the rest of the record)."New value: +"Fields to return (reduces payload). Names are case-sensitive, and each fills one output field: DOI → doi, title → title, type → type, author → authors and authorCount, published / published-print / published-online → published, container-title → containerTitle, publisher → publisher, is-referenced-by-count → isReferencedByCount, score → score, abstract → abstract, volume → volume, issue → issue, page → page, article-number → articleNumber, ISSN → issn, updated-by → updatedBy, update-to → updateTo. A selected field absent from a work means the record does not deposit it. DOI is always returned whether or not it is listed here, so every result stays resolvable by crossref_get_work, which also returns the fields this list does not cover (license, funder, references, and the rest of the record)."

Previous value: -[
-  "DOI",
-  "title",
-  "type",
-  "author",
-  "published",
-  "published-print",
-  "published-online",
-  "container-title",
-  "publisher",
-  "is-referenced-by-count",
-  "score",
-  "abstract",
-  "volume",
-  "issue",
-  "page",
-  "article-number",
-  "ISSN"
-]New value: +[
+  "DOI",
+  "title",
+  "type",
+  "author",
+  "published",
+  "published-print",
+  "published-online",
+  "container-title",
+  "publisher",
+  "is-referenced-by-count",
+  "score",
+  "abstract",
+  "volume",
+  "issue",
+  "page",
+  "article-number",
+  "ISSN",
+  "updated-by",
+  "update-to"
+]

Previous value: -"Sort direction (asc or desc)"New value: +"Sort direction (asc or desc). Applies only alongside sort; without one it has no effect."

Previous value: -"Number of results to return per page (1–100, default 20)"New value: +"Number of results to return per page (1–100 per call, default 20). A larger value, up to 1000, returns 100 and says so in notice — on an offset page the notice also names the offset that continues after the records returned."

Previous value: -100New value: +1000

Previous value: -"Sort field. The publication-date sorts (published, published-print, published-online) work with offset paging only — Crossref refuses them alongside cursor; every other sort works with either."New value: +"Sort field. Omitted, an offset page with a query term is ranked by relevance, and so is a cursor walk with one (sent as score). The publication-date sorts (published, published-print, published-online) work with offset paging only — Crossref refuses them alongside cursor; every other sort works with either."

Previous value: -"Guidance on an empty page, naming which of its three causes applies: a query nothing matched, an offset past the end of a list that did match, or a cursor walk that has reached the end of the list. On a page carrying records, present when authorLimit cut at least one work list, naming how many and the route to the rest, or when every query term and filter value was supplied blank, so the page lists the whole index unfiltered. A page needing more than one caveat carries them all in this one string."New value: +"Guidance on an empty page, naming which of its three causes applies: a query nothing matched, an offset past the end of a list that did match, or a cursor walk that has reached the end of the list. On a page carrying records, present when authorLimit cut at least one work list, naming how many and the route to the rest, or when every query term and filter value was supplied blank, so the page lists the whole index unfiltered. On any page, present when rows or authorLimit was above its per-call cap, naming the value requested and the cap applied — on an offset page with records remaining, also the offset that continues after the records returned, with the smaller rows that still fit when a full page there would pass the ~10K offset ceiling. A page needing more than one caveat carries them all in this one string."

Added value: +{
+  "description": "Works this record is an update notice for, in the entry shape updatedBy uses and in deposited order. Omitted when the record is not registered as a notice.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Update link",
+    "properties": {
+      "doi": {
+        "description": "DOI on the other side of the link: the notice, in updatedBy; the updated work, in updateTo. It is this work's own DOI when the update was made to this record in place.",
+        "type": "string"
+      },
+      "recordId": {
+        "description": "Retraction Watch record ID. Present only on retraction-watch entries.",
+        "type": "string"
+      },
+      "source": {
+        "description": "Who recorded the link: publisher, or retraction-watch for an entry Crossref carries from the Retraction Watch database",
+        "type": "string"
+      },
+      "type": {
+        "description": "Crossref update type as deposited: correction, erratum, corrigendum, addendum, retraction, withdrawal, expression_of_concern, new_version, new_edition, or another code",
+        "type": "string"
+      },
+      "updated": {
+        "additionalProperties": false,
+        "description": "Date the update was issued",
+        "properties": {
+          "day": {
+            "description": "Day of month",
+            "type": "number"
+          },
+          "month": {
+            "description": "Month (1–12)",
+            "type": "number"
+          },
+          "year": {
+            "description": "Year",
+            "type": "number"
+          }
+        },
+        "type": "object"
+      }
+    },
+    "required": [
+      "doi",
+      "type",
+      "source"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Update notices Crossref records against this work — corrections, errata, retractions, expressions of concern, withdrawals, new versions — in deposited order. Entries are never merged: the same notice DOI can appear once per source, typed differently by each. Omitted when none is recorded, which does not mean the work was never updated: coverage depends on publisher and Retraction Watch deposits.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Update link",
+    "properties": {
+      "doi": {
+        "description": "DOI on the other side of the link: the notice, in updatedBy; the updated work, in updateTo. It is this work's own DOI when the update was made to this record in place.",
+        "type": "string"
+      },
+      "recordId": {
+        "description": "Retraction Watch record ID. Present only on retraction-watch entries.",
+        "type": "string"
+      },
+      "source": {
+        "description": "Who recorded the link: publisher, or retraction-watch for an entry Crossref carries from the Retraction Watch database",
+        "type": "string"
+      },
+      "type": {
+        "description": "Crossref update type as deposited: correction, erratum, corrigendum, addendum, retraction, withdrawal, expression_of_concern, new_version, new_edition, or another code",
+        "type": "string"
+      },
+      "updated": {
+        "additionalProperties": false,
+        "description": "Date the update was issued",
+        "properties": {
+          "day": {
+            "description": "Day of month",
+            "type": "number"
+          },
+          "month": {
+            "description": "Month (1–12)",
+            "type": "number"
+          },
+          "year": {
+            "description": "Year",
+            "type": "number"
+          }
+        },
+        "type": "object"
+      }
+    },
+    "required": [
+      "doi",
+      "type",
+      "source"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Previous value: -"Abstract when deposited by the publisher. Many records lack abstracts. Publishers deposit it as JATS XML, so this is the text of that deposit with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and a formula the deposit encodes more than once — TeX beside MathML — appears once, in the first notation deposited."New value: +"Abstract when deposited by the publisher. Many records lack abstracts. Publishers deposit it as JATS XML, so this is the text of that deposit with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first."

Added value: +{
+  "description": "Article number, deposited by journals that number articles instead of paging them",
+  "type": "string"
+}

Added value: +{
+  "description": "Editors of the work, or of the book or proceedings containing it, in the entry shape authors use. Returned whole — never paged by offset and limit, and never counted in authorCount. Omitted when the record deposits none.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Author or contributor",
+    "properties": {
+      "affiliation": {
+        "description": "Institutional affiliations",
+        "items": {
+          "additionalProperties": false,
+          "description": "Affiliation",
+          "properties": {
+            "name": {
+              "description": "Affiliation name as deposited. Absent when the publisher asserted the organization by identifier alone, where ror carries it instead.",
+              "type": "string"
+            },
+            "ror": {
+              "description": "ROR identifier for the affiliated organization, when the deposit carries one. It is the whole identity of an affiliation deposited without a name.",
+              "type": "string"
+            }
+          },
+          "type": "object"
+        },
+        "type": "array"
+      },
+      "family": {
+        "description": "Family (last) name",
+        "type": "string"
+      },
+      "given": {
+        "description": "Given (first) name",
+        "type": "string"
+      },
+      "name": {
+        "description": "Name when no given/family split is available",
+        "type": "string"
+      },
+      "orcid": {
+        "description": "ORCID identifier URI",
+        "type": "string"
+      },
+      "sequence": {
+        "description": "Author order role (first, additional)",
+        "type": "string"
+      }
+    },
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "ISBN(s) as deposited — for a book chapter, those of the containing book. Omitted when the record deposits none.",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Issue of the container the work appears in",
+  "type": "string"
+}

Previous value: -"Which authors this page covers and the offset that reaches the next ones, or an explanation when the requested offset is past the end of the author list. Absent when the page holds the whole list."New value: +"When updatedBy is present, the update types Crossref records for this work with the source of each, and where the notice is read. Then which authors this page covers and the offset that reaches the next ones, or an explanation when the requested offset is past the end of the author list. Both share this one string when both apply. Absent when the page holds the whole author list and no update is recorded."

Added value: +{
+  "description": "Page range as deposited, e.g. \"357-362\"",
+  "type": "string"
+}

Added value: +{
+  "description": "Related identifiers — preprints and published versions, other versions, reviews, supplements, parts — grouped by relation type, identifier type, and asserting party, groups in Crossref's order and ids in deposited order. Returned whole. Omitted when the record deposits none.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Related identifiers sharing one relation type, identifier type, and asserting party",
+    "properties": {
+      "assertedBy": {
+        "description": "Whose deposit asserts the relation: subject (this work's depositor) or object (the related record's depositor, whose assertion Crossref shows here inverted)",
+        "type": "string"
+      },
+      "idType": {
+        "description": "Identifier scheme of ids: doi, uri, pmid, arxiv, accession, issn, isbn, or other",
+        "type": "string"
+      },
+      "ids": {
+        "description": "Related identifiers in deposited order. A DOI resolves through crossref_get_work only when Crossref registered it; one registered with another agency, such as DataCite, returns doi_not_found there.",
+        "items": {
+          "type": "string"
+        },
+        "type": "array"
+      },
+      "type": {
+        "description": "Relation type as deposited, read from this work toward ids: is-preprint-of, has-preprint, is-version-of, has-version, has-review, is-supplemented-by, references, has-part, and others",
+        "type": "string"
+      }
+    },
+    "required": [
+      "type",
+      "idType",
+      "assertedBy",
+      "ids"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Works this record is an update notice for, in the entry shape updatedBy uses and in deposited order. Omitted when the record is not registered as a notice.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Update link",
+    "properties": {
+      "doi": {
+        "description": "DOI on the other side of the link: the notice, in updatedBy; the updated work, in updateTo. It is this work's own DOI when the update was made to this record in place.",
+        "type": "string"
+      },
+      "recordId": {
+        "description": "Retraction Watch record ID. Present only on retraction-watch entries.",
+        "type": "string"
+      },
+      "source": {
+        "description": "Who recorded the link: publisher, or retraction-watch for an entry Crossref carries from the Retraction Watch database",
+        "type": "string"
+      },
+      "type": {
+        "description": "Crossref update type as deposited: correction, erratum, corrigendum, addendum, retraction, withdrawal, expression_of_concern, new_version, new_edition, or another code",
+        "type": "string"
+      },
+      "updated": {
+        "additionalProperties": false,
+        "description": "Date the update was issued",
+        "properties": {
+          "day": {
+            "description": "Day of month",
+            "type": "number"
+          },
+          "month": {
+            "description": "Month (1–12)",
+            "type": "number"
+          },
+          "year": {
+            "description": "Year",
+            "type": "number"
+          }
+        },
+        "type": "object"
+      }
+    },
+    "required": [
+      "doi",
+      "type",
+      "source"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Update notices Crossref records against this work — corrections, errata, retractions, expressions of concern, withdrawals, new versions — in deposited order. Entries are never merged: the same notice DOI can appear once per source, typed differently by each. Omitted when none is recorded, which does not mean the work was never updated: coverage depends on publisher and Retraction Watch deposits.",
+  "items": {
+    "additionalProperties": false,
+    "description": "Update link",
+    "properties": {
+      "doi": {
+        "description": "DOI on the other side of the link: the notice, in updatedBy; the updated work, in updateTo. It is this work's own DOI when the update was made to this record in place.",
+        "type": "string"
+      },
+      "recordId": {
+        "description": "Retraction Watch record ID. Present only on retraction-watch entries.",
+        "type": "string"
+      },
+      "source": {
+        "description": "Who recorded the link: publisher, or retraction-watch for an entry Crossref carries from the Retraction Watch database",
+        "type": "string"
+      },
+      "type": {
+        "description": "Crossref update type as deposited: correction, erratum, corrigendum, addendum, retraction, withdrawal, expression_of_concern, new_version, new_edition, or another code",
+        "type": "string"
+      },
+      "updated": {
+        "additionalProperties": false,
+        "description": "Date the update was issued",
+        "properties": {
+          "day": {
+            "description": "Day of month",
+            "type": "number"
+          },
+          "month": {
+            "description": "Month (1–12)",
+            "type": "number"
+          },
+          "year": {
+            "description": "Year",
+            "type": "number"
+          }
+        },
+        "type": "object"
+      }
+    },
+    "required": [
+      "doi",
+      "type",
+      "source"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Volume of the container the work appears in",
+  "type": "string"
+}

Previous value: -"Abstract when present in the indexed record — the text of the publisher’s JATS deposit, with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and a formula the deposit encodes more than once appears once, in the first notation deposited"New value: +"Abstract when present in the indexed record — the text of the publisher’s JATS deposit, with markup removed and character references decoded; a link keeps its tag only where its href holds an address the text it wraps does not already carry, and each formula appears once — MathML as the TeX annotation it carries, otherwise written out linearly (x_i, A^{−1}, √(m), (a+b)/c), and TeX deposited beside MathML in whichever notation comes first"

Added value: +[
+  {
+    "const": "",
+    "type": "string"
+  },
+  {
+    "description": "Funder registry ID or funder DOI, e.g. \"100000001\"",
+    "pattern": "^(?:(?:https?:\\/\\/(?:dx\\.)?doi\\.org\\/|doi:)?10\\.13039\\/)?\\d+$",
+    "type": "string"
+  }
+]

Removed value: -"^(?:(?:https?:\\/\\/(?:dx\\.)?doi\\.org\\/|doi:)?10\\.13039\\/)?\\d+$"

Removed value: -"string"

Previous value: -"number"New value: +"integer"

Previous value: -"Cursor token for deep paging of the funded-works list when include_works is true. Pass \"*\" to start the walk at the newest work, then pass the nextWorksCursor value from each response. Has no offset ceiling and cannot be combined with works_offset. Each token runs about 1500 characters and is returned on both result surfaces, a fixed cost per page — raise rows to spread it across more works on a long walk."New value: +"Cursor token for deep paging of the funded-works list when include_works is true. Pass \"*\" to start the walk at the most recently registered work, then pass the nextWorksCursor value from each response. A walk runs by the date each DOI was registered with Crossref, newest first, not by publication date — Crossref does not walk a publication-date sort by cursor. Has no offset ceiling and cannot be combined with works_offset."

Previous value: -"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `funder_not_found`: Funder DOI lookup returned 404 — funder is not in the Crossref Funder Registry. `ambiguous_funder`: include_works is true but the name query matched more than one funder, making the target ambiguous. `offset_too_large`: offset + rows exceeds the 100000-record ceiling Crossref allows on funder name search. `works_offset_too_large`: works_offset + rows exceeds the 10000-record ceiling Crossref allows on a funded-works list. `works_cursor_offset_conflict`: include_works is true and works_cursor was supplied alongside a works_offset above zero. Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `invalid_cursor`: Crossref did not recognize the cursor token (HTTP 404 cursor-invalid). `invalid_parameter`: Crossref rejected a parameter value (a filter value of the wrong type or form), or answered HTTP 400 with a body that did not parse. `funder_not_found`: Funder DOI lookup returned 404 — funder is not in the Crossref Funder Registry. `ambiguous_funder`: include_works is true but the name query matched more than one funder, making the target ambiguous. `offset_too_large`: offset + rows exceeds the 100000-record ceiling Crossref allows on funder name search. `works_offset_too_large`: works_offset + rows exceeds the 10000-record ceiling Crossref allows on a funded-works list. `works_cursor_offset_conflict`: include_works is true and works_cursor was supplied alongside a works_offset above zero. Other values are possible when a failure originates below the handler."

Previous value: -[
-  "rate_limited",
-  "upstream_unavailable",
-  "malformed_response",
-  "request_timeout",
-  "funder_not_found",
-  "ambiguous_funder",
-  "offset_too_large",
-  "works_offset_too_large",
-  "works_cursor_offset_conflict"
-]New value: +[
+  "rate_limited",
+  "upstream_unavailable",
+  "malformed_response",
+  "request_timeout",
+  "invalid_cursor",
+  "invalid_parameter",
+  "funder_not_found",
+  "ambiguous_funder",
+  "offset_too_large",
+  "works_offset_too_large",
+  "works_cursor_offset_conflict"
+]

Previous value: -"Page of works funded by the matched funder, ordered by publication date (newest first). Only present when include_works is true."New value: +"Page of works funded by the matched funder, newest first — by publication date on an offset page, by Crossref registration date on a works_cursor page. Only present when include_works is true."

Previous value: -"Guidance on a page that needs a caveat: a query nothing matched, an offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, or a returned funder that the Funder Registry has deprecated in favor of another entry. Absent otherwise. A page needing more than one caveat carries them all in this one string."New value: +"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, a returned funder that the Funder Registry has deprecated in favor of another entry, or a query or funder_doi supplied blank with nothing else to search by, so the page lists every funder unfiltered. Absent otherwise. A page needing more than one caveat carries them all in this one string."

Previous value: -"When true, also return a page of the journal's most recent works by publication date. Requires an unambiguous journal — pass issn when a title query matches more than one. A journal with no ISSN registered has no addressable works list; the works lookup is then skipped and the notice enrichment says so."New value: +"When true, also return a page of the journal's most recent works — newest published first on an offset page, newest registered first on a works_cursor walk. Requires an unambiguous journal — pass issn when a title query matches more than one. A journal with no ISSN registered has no addressable works list; the works lookup is then skipped and the notice enrichment says so."

Added value: +[
+  {
+    "const": "",
+    "type": "string"
+  },
+  {
+    "description": "ISSN, e.g. \"1234-5678\"",
+    "pattern": "^\\d{4}-?\\d{3}[\\dX]$",
+    "type": "string"
+  }
+]

Removed value: -"^\\d{4}-?\\d{3}[\\dX]$"

Removed value: -"string"

Previous value: -"number"New value: +"integer"

Previous value: -"Cursor token for deep paging of the journal works list when include_works is true. Pass \"*\" to start the walk at the newest work, then pass the nextWorksCursor value from each response. Has no offset ceiling and cannot be combined with works_offset. Each token runs about 1500 characters and is returned on both result surfaces, a fixed cost per page — raise rows to spread it across more works on a long walk."New value: +"Cursor token for deep paging of the journal works list when include_works is true. Pass \"*\" to start the walk at the most recently registered work, then pass the nextWorksCursor value from each response. A walk runs by the date each DOI was registered with Crossref, newest first, not by publication date — Crossref does not walk a publication-date sort by cursor. Has no offset ceiling and cannot be combined with works_offset."

Previous value: -"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `issn_not_found`: ISSN lookup returned 404 — ISSN is not registered in Crossref. `ambiguous_journal`: include_works is true but the title query matched more than one journal, making the target ambiguous. `offset_too_large`: offset + rows exceeds the 100000-record ceiling Crossref allows on journal title search. `works_offset_too_large`: works_offset + rows exceeds the 10000-record ceiling Crossref allows on a journal works list. `works_cursor_offset_conflict`: include_works is true and works_cursor was supplied alongside a works_offset above zero. Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `invalid_cursor`: Crossref did not recognize the cursor token (HTTP 404 cursor-invalid). `invalid_parameter`: Crossref rejected a parameter value (a filter value of the wrong type or form), or answered HTTP 400 with a body that did not parse. `issn_not_found`: ISSN lookup returned 404 — ISSN is not registered in Crossref. `ambiguous_journal`: include_works is true but the title query matched more than one journal, making the target ambiguous. `offset_too_large`: offset + rows exceeds the 100000-record ceiling Crossref allows on journal title search. `works_offset_too_large`: works_offset + rows exceeds the 10000-record ceiling Crossref allows on a journal works list. `works_cursor_offset_conflict`: include_works is true and works_cursor was supplied alongside a works_offset above zero. Other values are possible when a failure originates below the handler."

Previous value: -[
-  "rate_limited",
-  "upstream_unavailable",
-  "malformed_response",
-  "request_timeout",
-  "issn_not_found",
-  "ambiguous_journal",
-  "offset_too_large",
-  "works_offset_too_large",
-  "works_cursor_offset_conflict"
-]New value: +[
+  "rate_limited",
+  "upstream_unavailable",
+  "malformed_response",
+  "request_timeout",
+  "invalid_cursor",
+  "invalid_parameter",
+  "issn_not_found",
+  "ambiguous_journal",
+  "offset_too_large",
+  "works_offset_too_large",
+  "works_cursor_offset_conflict"
+]

Previous value: -"Guidance on a page that needs a caveat: a query nothing matched, an offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, or an include_works request that was skipped because the matched journal has no registered ISSN to address its works list by. Absent otherwise."New value: +"Guidance on a page that needs a caveat: a query nothing matched, an offset or works_offset past the end of a list that did match, a page that stops at one of the route offset ceilings with records still unretrieved, an include_works request that was skipped because the matched journal has no registered ISSN to address its works list by, or a query or issn supplied blank with nothing else to search by, so the page lists every journal unfiltered. Absent otherwise. A page needing more than one caveat carries them all in this one string."

Previous value: -"Page of works from the matched journal, ordered by publication date (newest first). Requires include_works, and absent even then when the matched journal has no registered ISSN — the works list is addressable by ISSN alone, and the notice enrichment says so."New value: +"Page of works from the matched journal, newest first — by publication date on an offset page, by Crossref registration date on a works_cursor page. Requires include_works, and absent even then when the matched journal has no registered ISSN — the works list is addressable by ISSN alone, and the notice enrichment says so."

Previous value: -"Cursor token for deep paging. Pass \"*\" to start cursor-based paging (required past ~10K results), then pass the nextCursor value from each response until a response omits it, which means the list is exhausted. Cannot be combined with offset."New value: +"Cursor token for deep paging. Pass \"*\" to start cursor-based paging (required past ~10K results), then pass the nextCursor value from each response until a response omits it, which means the list is exhausted. Cannot be combined with offset, or with a publication-date sort (published, published-print, published-online), which Crossref does not walk by cursor."

Previous value: -"Fields to return (reduces payload). Names are case-sensitive. Useful set: DOI, title, author, published, type, is-referenced-by-count, abstract, container-title, publisher, score. DOI is always returned whether or not it is listed here, so every result stays resolvable by crossref_get_work."New value: +"Fields to return (reduces payload). Names are case-sensitive, and each fills one output field: DOI → doi, title → title, type → type, author → authors and authorCount, published / published-print / published-online → published, container-title → containerTitle, publisher → publisher, is-referenced-by-count → isReferencedByCount, score → score, abstract → abstract, volume → volume, issue → issue, page → page, article-number → articleNumber, ISSN → issn. A selected field absent from a work means the record does not deposit it. DOI is always returned whether or not it is listed here, so every result stays resolvable by crossref_get_work, which also returns the fields this list does not cover (license, funder, references, and the rest of the record)."

Added value: +"Crossref select name"

Added value: +[
+  "DOI",
+  "title",
+  "type",
+  "author",
+  "published",
+  "published-print",
+  "published-online",
+  "container-title",
+  "publisher",
+  "is-referenced-by-count",
+  "score",
+  "abstract",
+  "volume",
+  "issue",
+  "page",
+  "article-number",
+  "ISSN"
+]

Previous value: -"Structured filter object using Crossref hyphen-separated keys. All values must be strings. Boolean flag keys (has-abstract, has-references, has-full-text) require string values \"true\" or \"false\". Example: {\"type\":\"journal-article\",\"has-abstract\":\"true\",\"from-pub-date\":\"2023-01-01\",\"directory\":\"DOAJ\"}"New value: +"Structured filter object using Crossref hyphen-separated keys. All values must be strings. Boolean flag keys (has-abstract, has-references, has-full-text) require string values \"true\" or \"false\". Example: {\"type\":\"journal-article\",\"has-abstract\":\"true\",\"from-pub-date\":\"2023-01-01\"}"

Added value: +9007199254740991

Previous value: -"number"New value: +"integer"

Added value: +[
+  {
+    "const": "",
+    "type": "string"
+  },
+  {
+    "description": "Sort direction",
+    "enum": [
+      "asc",
+      "desc"
+    ],
+    "type": "string"
+  }
+]

Removed value: -[
-  "asc",
-  "desc"
-]

Removed value: -"string"

Previous value: -"number"New value: +"integer"

Added value: +[
+  {
+    "const": "",
+    "type": "string"
+  },
+  {
+    "description": "Crossref sort field",
+    "enum": [
+      "relevance",
+      "score",
+      "is-referenced-by-count",
+      "published",
+      "published-print",
+      "published-online",
+      "deposited",
+      "indexed",
+      "created",
+      "updated",
+      "references-count"
+    ],
+    "type": "string"
+  }
+]

Previous value: -"Sort field"New value: +"Sort field. The publication-date sorts (published, published-print, published-online) work with offset paging only — Crossref refuses them alongside cursor; every other sort works with either."

Removed value: -[
-  "relevance",
-  "score",
-  "is-referenced-by-count",
-  "published",
-  "published-print",
-  "published-online",
-  "deposited",
-  "indexed",
-  "created",
-  "updated",
-  "references-count"
-]

Removed value: -"string"

Previous value: -"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `cursor_offset_conflict`: Both cursor and offset were supplied in the same request. `offset_too_large`: The requested offset exceeds the ~10K Crossref limit for offset-based paging. Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `rate_limited`: Crossref answered HTTP 429 and the limit did not clear inside the retry budget. `upstream_unavailable`: Crossref was unreachable, returned a 5xx status, or served an HTML error page instead of JSON. `malformed_response`: Crossref returned HTTP 200 with a body that is not valid JSON. `request_timeout`: Crossref did not respond within CROSSREF_TIMEOUT_MS, or answered HTTP 408/504. `unknown_filter`: Crossref rejected a filter key it does not recognize (filter-not-available). `sort_cursor_conflict`: A publication-date sort (published, published-print, published-online) was combined with cursor paging, which Crossref refuses. `invalid_cursor`: Crossref did not recognize the cursor token (HTTP 404 cursor-invalid). `invalid_parameter`: Crossref rejected a parameter value (a filter value of the wrong type or form), or answered HTTP 400 with a body that did not parse. `cursor_offset_conflict`: Both cursor and offset were supplied in the same request. `offset_too_large`: The requested offset exceeds the ~10K Crossref limit for offset-based paging. Other values are possible when a failure originates below the handler."

Previous value: -[
-  "rate_limited",
-  "upstream_unavailable",
-  "malformed_response",
-  "request_timeout",
-  "cursor_offset_conflict",
-  "offset_too_large"
-]New value: +[
+  "rate_limited",
+  "upstream_unavailable",
+  "malformed_response",
+  "request_timeout",
+  "unknown_filter",
+  "sort_cursor_conflict",
+  "invalid_cursor",
+  "invalid_parameter",
+  "cursor_offset_conflict",
+  "offset_too_large"
+]

Previous value: -"Guidance on an empty page, naming which of its three causes applies: a query nothing matched, an offset past the end of a list that did match, or a cursor walk that has reached the end of the list. On a page carrying records, present only when authorLimit cut at least one work list, naming how many and the route to the rest."New value: +"Guidance on an empty page, naming which of its three causes applies: a query nothing matched, an offset past the end of a list that did match, or a cursor walk that has reached the end of the list. On a page carrying records, present when authorLimit cut at least one work list, naming how many and the route to the rest, or when every query term and filter value was supplied blank, so the page lists the whole index unfiltered. A page needing more than one caveat carries them all in this one string."

Added value: +{
+  "description": "Article number, deposited by journals that number articles instead of paging them",
+  "type": "string"
+}

Added value: +{
+  "description": "ISSN(s) of the containing journal",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

Added value: +{
+  "description": "Issue of the container the work appears in",
+  "type": "string"
+}

Added value: +{
+  "description": "Page range as deposited, e.g. \"357-362\"",
+  "type": "string"
+}

Added value: +{
+  "description": "Volume of the container the work appears in",
+  "type": "string"
+}