Previous value: -"Country name. E.g., \"United States\"."New value: +"Country name, e.g. \"United States\". Common synonyms rank sites as the registry spelling does: USA and US as United States, UK and England as United Kingdom, Czech Republic as Czechia, Republic of Korea as South Korea, and PR, GU, VI, AS, and MP as the US territories, which the registry files as countries."

Previous value: -"State or province, compared with the state the site files. With city also given, a site that files no state still matches; without city, only sites filing this state match."New value: +"State or province, compared with the state the site files. A US state or DC abbreviation (WA, DC) is compared as its full name when the country is the United States or a synonym for it. With city also given, a site that files no state still matches; without city, only sites filing this state match."

Previous value: -"Patient location as `{ country (required), state?, city? }`. Country is required; state/city narrow the match. For radius-based geographic search, use clinicaltrials_search_studies with geoFilter."New value: +"Patient location as `{ country (required), state?, city? }`. Country is required; state/city narrow the match. Every part given must hold for the same study site: country and state are compared with the site's filed country and state, while city is matched against the site's whole location text, so a site filed under a borough or neighbouring town that names the city still counts. For radius-based geographic search, use clinicaltrials_search_studies with geoFilter."

Previous value: -"State or province."New value: +"State or province, compared with the state the site files. With city also given, a site that files no state still matches; without city, only sites filing this state match."

Previous value: -"Machine-readable failure mode. Declared by this tool: `blank_value`: A conditions entry or location.country was supplied blank — empty, whitespace-only, or made only of `\"` characters, invisible format characters such as zero-width spaces, and whitespace, since `\"` is stripped before the query is built — or conditions was an empty list. `rate_limited`: ClinicalTrials.gov returned 429 after retry budget exhausted. Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `blank_value`: A conditions entry or location.country was supplied blank — empty, whitespace-only, or made only of `\"` characters, invisible format characters such as zero-width spaces, and whitespace, since `\"` is stripped before the query is built — or conditions was an empty list. `field_invalid`: A conditions entry carries an AREA[] expression naming a field ClinicalTrials.gov does not recognize or cannot search by value. `query_parse_error`: A conditions entry uses syntax the upstream Essie parser rejects — typically an unmatched `(` or `)`, or a `[` or `]` outside an AREA[…] expression. `request_too_long`: The conditions list or location makes the request URL longer than ClinicalTrials.gov accepts — several hundred conditions in one call. `rate_limited`: ClinicalTrials.gov returned 429 after retry budget exhausted. Other values are possible when a failure originates below the handler."

Previous value: -[
-  "blank_value",
-  "rate_limited"
-]New value: +[
+  "blank_value",
+  "field_invalid",
+  "query_parse_error",
+  "request_too_long",
+  "rate_limited"
+]

Previous value: -"The exact queryLocn string sent upstream: city/state/country AND-joined inside SEARCH[Location](…) so every part must match the same site, each part quoted unless it is a single run of letters and digits (Toronto stays bare; \"United States\", \"Winston-Salem\", and \"L'Aquila\" are quoted), with any embedded double quote stripped and any backslash in a quoted part doubled. Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."New value: +"The exact queryLocn string sent upstream: the parts AND-joined inside SEARCH[Location](…) so every part must match the same site. The city is a search term, quoted unless it is a single run of letters and digits (Toronto stays bare; \"Winston-Salem\" and \"L'Aquila\" are quoted); the state is AREA[LocationState]\"…\", ORed with AREA[LocationState]MISSING when a city is given; the country is AREA[LocationCountry]\"…\", ORed with the same spelling without diacritics when it carries any (México also tries Mexico). Any embedded double quote is stripped and any backslash in a quoted value doubled. Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."

Previous value: -"Patient age in years."New value: +"Patient age as a whole number in ageUnit (years unless ageUnit says otherwise)."

Added value: +{
+  "description": "Unit age is given in: years (default), months, weeks, or days; case and singular forms are accepted. Use a smaller unit for an infant or young child whose eligibility window is narrower than a year — age 7 with ageUnit \"months\" matches a study registered for 6 Months to 8 Months, which no whole number of years reaches. ClinicalTrials.gov compares ages across units, so the unit only sets how precisely age is stated.",
+  "enum": [
+    "years",
+    "months",
+    "weeks",
+    "days"
+  ],
+  "type": "string"
+}

Previous value: -"Medical conditions or diagnoses, e.g. [\"Type 2 Diabetes\", \"Hypertension\"]. Each entry is matched as a condition (multi-word entries match as a phrase); multiple entries are combined with OR, so studies for any listed condition qualify. Returned studies are re-ranked so those whose own condition list names a requested condition rank above tangential matches the upstream fuzzy search pulls in via the MeSH umbrella."New value: +"Medical conditions or diagnoses, e.g. [\"Type 2 Diabetes\", \"Hypertension\"]. Each entry is matched as a condition: an entry containing whitespace is quoted and matches as a phrase, and any other entry is sent as written, punctuation included (double quotes are stripped from every entry); multiple entries are combined with OR, so studies for any listed condition qualify. Returned studies are re-ranked so those whose own condition list names a requested condition rank above tangential matches the upstream fuzzy search pulls in via the MeSH umbrella."

Previous value: -"Cap on the sites returned per candidate. Each candidate keeps only the sites matching the requested location at the narrowest level that matched (city, else state, else country), capped at this many; the rest of the study's registered sites are omitted. The cap governs those matched sites — when none of them is recruiting, one recruiting site is added on top of it (the nearest to any matched site, measured before this cap, when coordinates allow — in the requested country whenever a site there recruits), so a candidate can carry one site more than this. Raise it to see more nearby sites, or fetch the complete site list with clinicaltrials_get_study_record. Each candidate reports totalLocations / matchedLocations / locationsTruncated / nearestRecruitingSiteAdded in locationSummary only when the bound actually dropped sites."New value: +"Cap on the sites returned per candidate. Each candidate keeps only the sites matching the requested location at the narrowest level that matched (city, else state, else country), capped at this many; the rest of the study's registered sites are omitted. The cap governs those matched sites — when none of them is recruiting, one recruiting site is added on top of it (the nearest to any matched site, measured before this cap, when coordinates allow — in the requested country whenever a site there recruits), so a candidate can carry one site more than this. Raise it to see more nearby sites — there is no upper bound, and a limit past the matched sites returns all of them — or fetch the complete site list with clinicaltrials_get_study_record. Each candidate reports totalLocations / matchedLocations / locationsTruncated / nearestRecruitingSiteAdded in locationSummary only when the bound actually dropped sites."

Previous value: -500New value: +9007199254740991

Previous value: -"Maximum results to return."New value: +"Maximum candidates to return, 1–1000. Each call returns at most 50; a larger value returns 50, reported in truncated/shown/cap when more studies match, and the searchCriteria replay through clinicaltrials_search_studies pages the rest."

Previous value: -50New value: +1000

Added value: +{
+  "description": "The tool's per-call cap, served in place of the requested maxResults when truncated is true.",
+  "exclusiveMinimum": 0,
+  "maximum": 9007199254740991,
+  "type": "integer"
+}

Previous value: -"When no studies matched, recovery guidance that identifies which filter stage collapsed and suggests how to broaden. When studies are returned, one caveat for the whole response: candidates were matched on demographics, location, recruitment status, and a fuzzy condition search, not on inclusion/exclusion criteria."New value: +"When no studies matched, recovery guidance that identifies which filter stage collapsed and suggests how to broaden. When studies are returned, one caveat for the whole response: candidates were matched on demographics, location, recruitment status, and a fuzzy condition search, not on inclusion/exclusion criteria. When maxResults was above the tool's per-call cap and more studies match, a sentence follows stating the requested, served, and total counts and pointing at the searchCriteria replay."

Previous value: -"Patient age."New value: +"Patient age, in ageUnit when present, else in years."

Added value: +{
+  "description": "The unit age was given in. Present only for months, weeks, or days; absent means years.",
+  "enum": [
+    "years",
+    "months",
+    "weeks",
+    "days"
+  ],
+  "type": "string"
+}

Previous value: -"The exact queryLocn string sent upstream (city/state/country, multi-word components quoted, AND-joined). Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."New value: +"The exact queryLocn string sent upstream: city/state/country AND-joined inside SEARCH[Location](…) so every part must match the same site, each part quoted unless it is a single run of letters and digits (Toronto stays bare; \"United States\", \"Winston-Salem\", and \"L'Aquila\" are quoted), with any embedded double quote stripped and any backslash in a quoted part doubled. Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."

Added value: +{
+  "description": "Candidates returned when truncated is true.",
+  "maximum": 9007199254740991,
+  "minimum": 0,
+  "type": "integer"
+}

Added value: +{
+  "description": "True when maxResults was above the tool's per-call cap and more studies match than were returned. Absent otherwise.",
+  "type": "boolean"
+}

Previous value: -"Machine-readable failure mode. Declared by this tool: `blank_value`: A parameter was supplied with a blank, whitespace-only, or empty-list value. `rate_limited`: ClinicalTrials.gov returned 429 after retry budget exhausted. Other values are possible when a failure originates below the handler."New value: +"Machine-readable failure mode. Declared by this tool: `blank_value`: A conditions entry or location.country was supplied blank — empty, whitespace-only, or made only of `\"` characters, invisible format characters such as zero-width spaces, and whitespace, since `\"` is stripped before the query is built — or conditions was an empty list. `rate_limited`: ClinicalTrials.gov returned 429 after retry budget exhausted. Other values are possible when a failure originates below the handler."

Previous value: -"Recovery guidance when no studies matched — identifies which filter stage collapsed and suggests how to broaden. Absent when results are returned."New value: +"When no studies matched, recovery guidance that identifies which filter stage collapsed and suggests how to broaden. When studies are returned, one caveat for the whole response: candidates were matched on demographics, location, recruitment status, and a fuzzy condition search, not on inclusion/exclusion criteria."

Previous value: -"Matching studies with eligibility and location fields. Each candidate's protocolSection.contactsLocationsModule.locations is BOUNDED to the sites matching the requested location (capped at locationLimit) plus, when none of those is recruiting, one added recruiting site — not the study's full registered site list. The added site is the one nearest any matched site by published coordinates, taken from the requested country whenever a site there recruits, and carries distanceMi (miles to that nearest matched site); when the matched or recruiting sites publish no coordinates it is the first in match order and carries no distanceMi. A candidate whose sites were bounded also carries a top-level locationSummary object — { totalLocations, matchedLocations, locationsTruncated, nearestRecruitingSiteAdded?, retrieveFullStudyWith } — absent when nothing was dropped; nearestRecruitingSiteAdded is present only when that extra site was added (the key keeps its name in the match-order fallback). Fetch a study's complete record and site list with clinicaltrials_get_study_record."New value: +"Candidate studies with their demographic limits (age, sex, healthy volunteers), contacts, and location fields — matched on age, sex, location, recruitment status, and the fuzzy condition search; inclusion/exclusion criteria are not checked and are not in these records, so review each candidate with clinicaltrials_get_study_record. Each candidate's protocolSection.contactsLocationsModule.locations is BOUNDED to the sites matching the requested location (capped at locationLimit) plus, when none of those is recruiting, one added recruiting site — not the study's full registered site list. The added site is the one nearest any matched site by published coordinates, taken from the requested country whenever a site there recruits, and carries distanceMi (miles to that nearest matched site); when the matched or recruiting sites publish no coordinates it is the first in match order and carries no distanceMi. A candidate whose sites were bounded also carries a top-level locationSummary object — { totalLocations, matchedLocations, locationsTruncated, nearestRecruitingSiteAdded?, retrieveFullStudyWith } — absent when nothing was dropped; nearestRecruitingSiteAdded is present only when that extra site was added (the key keeps its name in the match-order fallback). Fetch a study's complete record and site list with clinicaltrials_get_study_record."

Previous value: -"Cap on the sites returned per candidate. Each candidate keeps only the sites matching the requested location at the narrowest level that matched (city, else state, else country), capped at this many; the rest of the study's registered sites are omitted. The cap governs those matched sites — when none of them is recruiting, the candidate's nearest recruiting site is added on top of it, so a candidate can carry one site more than this. Raise it to see more nearby sites, or fetch the complete site list with clinicaltrials_get_study_record. Each candidate reports totalLocations / matchedLocations / locationsTruncated / nearestRecruitingSiteAdded in locationSummary only when the bound actually dropped sites."New value: +"Cap on the sites returned per candidate. Each candidate keeps only the sites matching the requested location at the narrowest level that matched (city, else state, else country), capped at this many; the rest of the study's registered sites are omitted. The cap governs those matched sites — when none of them is recruiting, one recruiting site is added on top of it (the nearest to any matched site, measured before this cap, when coordinates allow — in the requested country whenever a site there recruits), so a candidate can carry one site more than this. Raise it to see more nearby sites, or fetch the complete site list with clinicaltrials_get_study_record. Each candidate reports totalLocations / matchedLocations / locationsTruncated / nearestRecruitingSiteAdded in locationSummary only when the bound actually dropped sites."

Previous value: -"Matching studies with eligibility and location fields. Each candidate's protocolSection.contactsLocationsModule.locations is BOUNDED to the sites matching the requested location (capped at locationLimit) plus, when none of those is recruiting, the candidate's nearest recruiting site — not the study's full registered site list. A candidate whose sites were bounded also carries a top-level locationSummary object — { totalLocations, matchedLocations, locationsTruncated, nearestRecruitingSiteAdded?, retrieveFullStudyWith } — absent when nothing was dropped; nearestRecruitingSiteAdded is present only when that extra site was added. Fetch a study's complete record and site list with clinicaltrials_get_study_record."New value: +"Matching studies with eligibility and location fields. Each candidate's protocolSection.contactsLocationsModule.locations is BOUNDED to the sites matching the requested location (capped at locationLimit) plus, when none of those is recruiting, one added recruiting site — not the study's full registered site list. The added site is the one nearest any matched site by published coordinates, taken from the requested country whenever a site there recruits, and carries distanceMi (miles to that nearest matched site); when the matched or recruiting sites publish no coordinates it is the first in match order and carries no distanceMi. A candidate whose sites were bounded also carries a top-level locationSummary object — { totalLocations, matchedLocations, locationsTruncated, nearestRecruitingSiteAdded?, retrieveFullStudyWith } — absent when nothing was dropped; nearestRecruitingSiteAdded is present only when that extra site was added (the key keeps its name in the match-order fallback). Fetch a study's complete record and site list with clinicaltrials_get_study_record."

Previous value: -"The exact queryLocn string sent upstream (city/state/country joined). Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."New value: +"The exact queryLocn string sent upstream (city/state/country, multi-word components quoted, AND-joined). Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

Added value: +false

Added value: +false

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

Added value: +[
+  {
+    "not": {
+      "required": [
+        "error"
+      ]
+    },
+    "required": [
+      "studies",
+      "searchCriteria",
+      "funnel"
+    ]
+  },
+  {
+    "required": [
+      "error"
+    ]
+  }
+]

Added value: +{
+  "additionalProperties": {},
+  "description": "Present when the call failed. Absent on success.",
+  "properties": {
+    "code": {
+      "description": "JSON-RPC error code for this failure.",
+      "maximum": 9007199254740991,
+      "minimum": -9007199254740991,
+      "type": "integer"
+    },
+    "data": {
+      "additionalProperties": {},
+      "properties": {
+        "reason": {
+          "description": "Machine-readable failure mode. Declared by this tool: `blank_value`: A parameter was supplied with a blank, whitespace-only, or empty-list value. `rate_limited`: ClinicalTrials.gov returned 429 after retry budget exhausted. Other values are possible when a failure originates below the handler.",
+          "examples": [
+            "blank_value",
+            "rate_limited"
+          ],
+          "type": "string"
+        },
+        "recovery": {
+          "additionalProperties": {},
+          "description": "Actionable next step for the caller.",
+          "properties": {
+            "hint": {
+              "type": "string"
+            }
+          },
+          "required": [
+            "hint"
+          ],
+          "type": "object"
+        },
+        "retryable": {
+          "description": "Whether retrying may succeed.",
+          "type": "boolean"
+        }
+      },
+      "type": "object"
+    },
+    "message": {
+      "description": "Human-readable description of what went wrong.",
+      "type": "string"
+    }
+  },
+  "required": [
+    "code",
+    "message"
+  ],
+  "type": "object"
+}

Removed value: -[
-  "studies",
-  "searchCriteria",
-  "funnel"
-]

Added value: +{
+  "default": 10,
+  "description": "Cap on the sites returned per candidate. Each candidate keeps only the sites matching the requested location at the narrowest level that matched (city, else state, else country), capped at this many; the rest of the study's registered sites are omitted. The cap governs those matched sites — when none of them is recruiting, the candidate's nearest recruiting site is added on top of it, so a candidate can carry one site more than this. Raise it to see more nearby sites, or fetch the complete site list with clinicaltrials_get_study_record. Each candidate reports totalLocations / matchedLocations / locationsTruncated / nearestRecruitingSiteAdded in locationSummary only when the bound actually dropped sites.",
+  "maximum": 500,
+  "minimum": 1,
+  "type": "integer"
+}

Previous value: -"Matching studies with eligibility and location fields."New value: +"Matching studies with eligibility and location fields. Each candidate's protocolSection.contactsLocationsModule.locations is BOUNDED to the sites matching the requested location (capped at locationLimit) plus, when none of those is recruiting, the candidate's nearest recruiting site — not the study's full registered site list. A candidate whose sites were bounded also carries a top-level locationSummary object — { totalLocations, matchedLocations, locationsTruncated, nearestRecruitingSiteAdded?, retrieveFullStudyWith } — absent when nothing was dropped; nearestRecruitingSiteAdded is present only when that extra site was added. Fetch a study's complete record and site list with clinicaltrials_get_study_record."

Removed value: -1

Previous value: -"Normalized search criteria applied to this eligibility query."New value: +"Normalized search criteria applied to this eligibility query, including the exact upstream query strings needed to reproduce the full match set via clinicaltrials_search_studies (replay with includeUnknownEnrollment=true, which find_eligible always sets)."

Added value: +{
+  "description": "The exact AREA[] advancedFilter (age range, plus sex/healthy-volunteer when constrained) sent upstream. Pass as advancedFilter to clinicaltrials_search_studies to reproduce the demographic constraints.",
+  "type": "string"
+}

Added value: +{
+  "description": "The exact queryCond string sent upstream (multi-word terms quoted, OR-joined). Pass as conditionQuery to clinicaltrials_search_studies to reproduce the full match set beyond the maxResults cap.",
+  "type": "string"
+}

Previous value: -"Location searched."New value: +"The exact queryLocn string sent upstream (city/state/country joined). Pass as locationQuery to clinicaltrials_search_studies to reproduce the location filter beyond the maxResults cap."

Added value: +{
+  "description": "The status filter applied ([\"RECRUITING\"] when recruitingOnly). Pass as statusFilter to clinicaltrials_search_studies. Absent when recruitingOnly is false.",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

Previous value: -"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words plus AND/OR/NOT. `[ ]` are reserved; `( )` group sub-expressions when matched; `,` acts as AND."New value: +"Medical conditions or diagnoses, e.g. [\"Type 2 Diabetes\", \"Hypertension\"]. Each entry is matched as a condition (multi-word entries match as a phrase); multiple entries are combined with OR, so studies for any listed condition qualify. Returned studies are re-ranked so those whose own condition list names a requested condition rank above tangential matches the upstream fuzzy search pulls in via the MeSH umbrella."

Previous value: -"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words only — reserved chars `[ ] ( ) ,` inside an entry will fail."New value: +"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words plus AND/OR/NOT. `[ ]` are reserved; `( )` group sub-expressions when matched; `,` acts as AND."

Previous value: -"Match counts at each filter stage. Diagnoses where the funnel collapsed on sparse results — e.g., conditionMatched=298 but demographicsMatched=2 means age/sex/status are the constraint."New value: +"Match counts at each filter stage. Shows where the funnel collapsed — e.g., conditionMatched=298 but demographicsMatched=2 means age/sex/status are the constraint."

Removed value: -{
-  "description": "Hints when no studies match, with suggestions to broaden the search.",
-  "items": {
-    "type": "string"
-  },
-  "type": "array"
-}

Added value: +{
+  "description": "Recovery guidance when no studies matched — identifies which filter stage collapsed and suggests how to broaden. Absent when results are returned.",
+  "type": "string"
+}

Previous value: -"Search criteria used."New value: +"Normalized search criteria applied to this eligibility query."

Previous value: -"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words only — brackets, parentheses, and commas inside an entry will trip the upstream Essie parser."New value: +"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words only — reserved chars `[ ] ( ) ,` inside an entry will fail."

Previous value: -"Patient location."New value: +"Patient location as `{ country (required), state?, city? }`. Country is required; state/city narrow the match. For radius-based geographic search, use clinicaltrials_search_studies with geoFilter."

Previous value: -"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]."New value: +"Medical conditions or diagnoses. E.g., [\"Type 2 Diabetes\", \"Hypertension\"]. Plain words only — brackets, parentheses, and commas inside an entry will trip the upstream Essie parser."

Added value: +{
+  "additionalProperties": false,
+  "description": "Match counts at each filter stage. Diagnoses where the funnel collapsed on sparse results — e.g., conditionMatched=298 but demographicsMatched=2 means age/sex/status are the constraint.",
+  "properties": {
+    "conditionMatched": {
+      "description": "Studies matching the condition query alone (broadest stage).",
+      "type": "number"
+    },
+    "demographicsMatched": {
+      "description": "Studies matching the full filter set (condition + location + age/sex + status). Equal to totalCount.",
+      "type": "number"
+    },
+    "locationMatched": {
+      "description": "Studies matching condition + location — diagnoses geographic narrowing.",
+      "type": "number"
+    }
+  },
+  "required": [
+    "conditionMatched",
+    "locationMatched",
+    "demographicsMatched"
+  ],
+  "type": "object"
+}

Previous value: -[
-  "studies",
-  "searchCriteria"
-]New value: +[
+  "studies",
+  "searchCriteria",
+  "funnel"
+]

Previous value: -"Patient's biological sex. Use 'All' to include studies regardless of sex restrictions."New value: +"Patient's biological sex. Use 'ALL' to include studies regardless of sex restrictions."

Previous value: -[
-  "Female",
-  "Male",
-  "All"
-]New value: +[
+  "FEMALE",
+  "MALE",
+  "ALL"
+]

Previous value: -"Biological sex."New value: +"Patient's biological sex. Use 'All' to include studies regardless of sex restrictions."