io.github.cyanheads/clinicaltrialsgov-mcp-server
REMOTE · CLINICALTRIALS.CASEYJHAND.COM · 2 COMPONENTS
Search ClinicalTrials.gov: find studies, retrieve results, match patients to candidate trials.
Available components
Last scanned (15 hours ago)
Scores higher than 94% of remote servers
Reachable. Last reached 6 Nov 2026.
Category Health and Science
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security83
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Nothing on it is marked destructive, but we can't show that an anonymous caller can only read: full credit needs the server to list at least one tool and every tool to be verifiably read-only. We use a best-effort check of tool names and descriptions to tell read-only tools from tools that change things, so some genuinely read-only tools may not get full credit. Names that start with a read verb (get, list, read, search and similar) and accurate readOnlyHint annotations help. Meet that to earn full credit, or require authorisation. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC is configured correctly; the domain's records validate against the full chain to the root. View diagnostics → Pass
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability72
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 6869 tokens (~858/item across 8 items; 7 tools + 1 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management93
- Stability check failed: schema churn in the 30 days we've observed: 0 tool removals, 1 breaking changes, 0 auth/transport breaks, 0 additions. See how to fix → Fail
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 7 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 9 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
Checks we ran (13)
- TLS certificate
- Authorization
- HTTPS
- HSTS header
- DNSSEC
- Transport
- Schema quality
- Stability
- Tool coverage
- Injection markers
- Destructive annotations
- Judged manipulation
- MCP protocol
Does not apply to this hosted endpoint (2)
- Supply Chain SecurityScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
- Provenance & TransparencyScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
The score does not measure everything. What the score does not measure →
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 6 Nov 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 4 Nov 26 0
- Server version: 2.11.0 → 2.11.1 functional
- “clinicaltrials_search_studies” reworded the description of “advancedFilter” cosmetic
- “clinicaltrials_get_study_count” reworded the description of “advancedFilter” cosmetic
- 3 Nov 26 −1
- The server rewrote its instructions, which are the text every model session reads security
- New resource “clinicaltrialsgov-guide” functional
- Server version: 2.10.2 → 2.11.0 functional
- “clinicaltrials_find_eligible” reworded the description of “location” cosmetic
- “clinicaltrials_get_field_definitions” reworded the description of “includeIndexedOnly” cosmetic
- “clinicaltrials_get_study_count” reworded the description of “advancedFilter” cosmetic
- “clinicaltrials_search_studies” reworded the description of “advancedFilter” cosmetic
- “clinicaltrials_search_studies” reworded the description of “nctIds” cosmetic
- 26 Oct 26 0
- Server version: 2.10.1 → 2.10.2 functional
- 23 Oct 26 0
- Stability: pass → fail ▼ security
- Tool “clinicaltrials_get_study_results” rewrote its description, which is the text the model reads security
- Server version: 2.10.0 → 2.10.1 functional
- “clinicaltrials_find_eligible” added an optional parameter “ageUnit” cosmetic
- “clinicaltrials_find_eligible” reworded the description of “conditions” cosmetic
- “clinicaltrials_find_eligible” reworded the description of “age” cosmetic
- “clinicaltrials_find_eligible” reworded the description of “locationLimit” cosmetic
- “clinicaltrials_find_eligible” reworded the description of “maxResults” cosmetic
- “clinicaltrials_get_field_definitions” reworded the description of “limit” cosmetic
- “clinicaltrials_get_study_record” reworded the description of “locationLimit” cosmetic
- “clinicaltrials_get_study_record” reworded the description of “outcomeLimit” cosmetic
- “clinicaltrials_get_study_record” reworded the description of “referenceLimit” cosmetic
- “clinicaltrials_get_study_results” reworded the description of “adverseEventLimit” cosmetic
- “clinicaltrials_get_study_results” reworded the description of “nctIds” cosmetic
- “clinicaltrials_get_study_results” reworded the description of “outcomeLimit” cosmetic
- “clinicaltrials_search_studies” reworded the description of “pageSize” cosmetic
- 14 Oct 26 −1
- Tool “clinicaltrials_find_eligible” rewrote its description, which is the text the model reads security
- Tool “clinicaltrials_get_study_results” rewrote its description, which is the text the model reads security
- “clinicaltrials_get_study_results” made “nctIds” required, so existing callers break ▼ functional
- Server version: 2.9.11 → 2.10.0 functional
- “clinicaltrials_get_study_results” reworded the description of “outcomeOffset” cosmetic
- “clinicaltrials_get_study_results” reworded the description of “summary” cosmetic
- “clinicaltrials_search_studies” reworded the description of “fields” cosmetic
- “clinicaltrials_search_studies” reworded the description of “pageToken” cosmetic
- “clinicaltrials_search_studies” reworded the description of “phaseFilter” cosmetic
- “clinicaltrials_get_study_count” reworded the description of “phaseFilter” cosmetic
- “clinicaltrials_get_field_values” reworded the description of “fields” cosmetic
- “clinicaltrials_get_study_results” reworded the description of “outcomeLimit” cosmetic
- 6 Oct 26 0
- Server version: 2.9.10 → 2.9.11 functional
- 28 Sept 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 6 Nov 2026 · Probed https://clinicaltrials.caseyjhand.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=caseyjhand.com | CN=WE1,O=Google Trust Services,C=US | 2 Nov 2026 | 31 Jan 2027 | ECDSA 256 | ECDSA-SHA256 | 995a30681ab772540e934241ca1d576c |
| SANs: caseyjhand.com, *.caseyjhand.com | ||||||
| CN=WE1,O=Google Trust Services,C=US (CA) | CN=GTS Root R4,O=Google Trust Services LLC,C=US | 13 Dec 2023 | 20 Feb 2029 | ECDSA 256 | ECDSA-SHA384 | 7ff31977972c224a76155d13b6d685e3 |
| CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) | CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE | 15 Nov 2023 | 28 Jan 2028 | ECDSA 384 | SHA256-RSA | 7fe530bf331343bedd821610493d8a1b |
Background: What to check on a remote MCP endpoint →
DNSSEC secure
Validation of clinicaltrials.caseyjhand.com. — Secure
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | Trust anchor | 20326, 38696 | 8, 8 | Verified |
| com. | DS published | 19718 | 13 | Verified |
| caseyjhand.com. | DS published | 2371 | 13 | Verified |
| clinicaltrials.caseyjhand.com. | Verified address RRset verified with the apex keys |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000; includeSubDomains; preload |
| x-content-type-options | nosniff |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://clinicaltrials.caseyjhand.com/mcp | Verified | 200 | |
| http (plaintext) | http://clinicaltrials.caseyjhand.com/mcp | HTTPS enforced | 301 | https://clinicaltrials.caseyjhand.com/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
clinicaltrials_find_eligible Clinicaltrials Find Eligible ~893
Find candidate clinical trials for a patient profile. Provide age, sex, conditions, and location to get studies with their demographic limits, contact information, and recruiting locations. Candidates are matched on age, sex, location, recruitment status, and ClinicalTrials.gov's fuzzy condition search only — inclusion/exclusion criteria are not checked, and a candidate can exclude the requested condition, so review each one's criteria with clinicaltrials_get_study_record before treating it as a match. Results are re-ranked so studies whose own condition matches a requested condition surface above tangential matches from ClinicalTrials.gov's fuzzy condition search. Each candidate returns only the sites matching the requested location (capped by locationLimit), not the study's full registered site list — a large trial can register hundreds of sites worldwide. When none of a candidate's matched sites is recruiting, one recruiting site is added so an enrollable site is never hidden behind a closer closed one: the one nearest the matched sites by their published coordinates, in the requested country whenever a site there recruits, carrying distanceMi, or the first in match order when coordinates are missing. Fetch a study's complete record with clinicaltrials_get_study_record.
| Name | Type | Req | Description |
|---|---|---|---|
| age | integer | yes | Patient age as a whole number in ageUnit (years unless ageUnit says otherwise). |
| ageUnit | string | – | 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 —… |
| conditions | array | yes | 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… |
| healthyVolunteer | boolean | – | Whether the patient is a healthy volunteer. When true, only studies accepting healthy volunteers are queried. |
| location | object | yes | 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… |
| locationLimit | integer | – | 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;… |
| maxResults | integer | – | 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 clinicalt… |
| recruitingOnly | boolean | – | Only include actively recruiting studies. |
| sex | string | yes | Patient's biological sex. Use 'ALL' to include studies regardless of sex restrictions. |
| Name | Type | Req | Description |
|---|---|---|---|
| cap | integer | – | The tool's per-call cap, served in place of the requested maxResults when truncated is true. |
| error | object | – | Present when the call failed. Absent on success. |
| funnel | object | – | 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. |
| notice | string | – | 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 matc… |
| searchCriteria | object | – | 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 includeU… |
| shown | integer | – | Candidates returned when truncated is true. |
| studies | array | – | 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; incl… |
| totalCount | number | – | Total matching studies from the API. |
| truncated | boolean | – | True when maxResults was above the tool's per-call cap and more studies match than were returned. Absent otherwise. |
No examples provided.
clinicaltrials_get_field_definitions Clinicaltrials Get Field Definitions ~365
Resolve valid field names from the ClinicalTrials.gov data model — the canonical PascalCase identifiers (OverallStatus, EnrollmentCount, LeadSponsorName) accepted by the `fields`, `advancedFilter`, and `sort` parameters of other tools, and as input to clinicaltrials_get_field_values. Select a mode: `"search"` — keyword search returning ranked matches (pass `query`, e.g. "enrollment", "sponsor", "adverse events"); `"drill"` — drill into a specific section by dot-notation path (pass `path`, e.g. "protocolSection.designModule"); `"overview"` — top-level summary of all sections (no additional args).
| Name | Type | Req | Description |
|---|---|---|---|
| includeIndexedOnly | boolean | – | drill mode only. Also list index-only pieces (search-index fields such as StudyFirstPostYear) alongside the record fields. Default: false. |
| limit | integer | – | search mode only. Maximum results to return. Default: 20. A value at or past the match count returns every match. |
| mode | string | yes | Operation mode. "search" — keyword search (requires `query`); "drill" — drill into a section by path (requires `path`); "overview" — list all top-level sections (no other args needed). |
| path | string | – | drill mode only. Dot-notation path to drill into — e.g., "protocolSection.designModule", "protocolSection.eligibilityModule", "resultsSection". Returns the section's individual fields. |
| query | string | – | search mode only. Keyword to search field names by — e.g., "enrollment", "sponsor", "adverse events". Returns matching field names ranked by relevance with their full paths and data types. |
| Name | Type | Req | Description |
|---|---|---|---|
| cap | number | – | The limit cap applied to this search (search mode only). |
| error | object | – | Present when the call failed. Absent on success. |
| fields | array | – | Field definitions, ordered by relevance when mode is "search". |
| notice | string | – | Recovery guidance when search mode returns no matches, or a truncation note when results are capped. |
| resolvedPath | string | – | Resolved path when mode is "drill". |
| searchQuery | string | – | Echo of the keyword used in search mode. Absent for drill and overview. |
| shown | number | – | Number of fields returned (search mode only). |
| totalFields | number | – | Total fields returned. |
| totalMatches | number | – | Total fields matching the query before the limit cap was applied (search mode only). Compare against `shown` to size a follow-up limit, or to see that a capped result set is barely over the cap rathe… |
| truncated | boolean | – | True when the field list was capped by the limit parameter (search mode only). |
No examples provided.
clinicaltrials_get_field_values Clinicaltrials Get Field Values ~140
Discover valid values for ClinicalTrials.gov fields with study counts per value. Use to explore available filter options before building a search — e.g., valid OverallStatus, Phase, InterventionType, StudyType, or LeadSponsorClass values.
| Name | Type | Req | Description |
|---|---|---|---|
| fields | – | yes | PascalCase field name(s) to get value statistics for — an empty list is rejected, not treated as "every field". A comma- or pipe-joined string ("Phase,StudyType") is split into separate names. Exampl… |
| Name | Type | Req | Description |
|---|---|---|---|
| error | object | – | Present when the call failed. Absent on success. |
| fieldStats | array | – | One entry per requested field: canonical path, PascalCase piece name, data type, and the statistics variant that type carries — top values with study counts plus unique/longest for ENUM/STRING, trueC… |
| notice | string | – | Present when a longest value was cut to a preview — names, for each such field, the clinicaltrials_search_studies arguments that return its full text. |
No examples provided.
clinicaltrials_get_study_count Clinicaltrials Get Study Count ~1,458
Get total clinical trial study count from ClinicalTrials.gov matching a query, without fetching study data. Fast and lightweight. Use for quick statistics or to build breakdowns by calling multiple times with different filters (e.g., count by phase, count by status, count recruiting vs completed for a condition).
| Name | Type | Req | Description |
|---|---|---|---|
| advancedFilter | string | – | Advanced filter using AREA[FieldName]value syntax. Examples: "AREA[StudyType]INTERVENTIONAL", "AREA[EnrollmentCount]RANGE[100, 1000]", "AREA[Phase]PHASE2 AND AREA[StudyType]INTERVENTIONAL", "(AREA[Ph… |
| conditionQuery | string | – | Condition/disease-specific search. E.g., "Type 2 Diabetes", "non-small cell lung cancer". Matches Condition, BriefTitle, OfficialTitle, ConditionMeshTerm, ConditionAncestorTerm, Keyword, and NCTId. C… |
| includeUnknownEnrollment | boolean | – | Include studies whose EnrollmentCount is the upstream "unknown" sentinel (99999999). Excluded by default — the sentinel pollutes RANGE[N, MAX] queries. Set true for data-quality audits. |
| interventionQuery | string | – | Intervention/treatment search. E.g., "pembrolizumab", "cognitive behavioral therapy". Matches InterventionName, InterventionType, ArmGroupType, InterventionOtherName, BriefTitle, OfficialTitle, ArmGr… |
| locationQuery | string | – | Location search — city, state, country, or facility name. Matches LocationCity, LocationState, LocationCountry, LocationFacility, and LocationZip; a study matches when any of its sites does. Plain wo… |
| outcomeQuery | string | – | Search within outcome measure fields. Matches PrimaryOutcomeMeasure, SecondaryOutcomeMeasure, OtherOutcomeMeasure, and OutcomeMeasureTitle, plus their description counterparts PrimaryOutcomeDescripti… |
| phaseFilter | – | – | Filter by trial phase. Omit to count all phases — an empty list is rejected, not treated as "no filter". Values: EARLY_PHASE1, PHASE1, PHASE2, PHASE3, PHASE4, NA. Case and spacing variants ("Phase 3"… |
| query | string | – | General free-text search across all fields. Runs the 57-field relevance search ClinicalTrials.gov publishes for this parameter — NCTId, NCTIdAlias, OrgStudyId, SecondaryId, Acronym, BriefTitle, Offic… |
| sponsorQuery | string | – | Sponsor/collaborator name search. Matches LeadSponsorName, CollaboratorName, and OrgFullName. Plain words plus AND/OR/NOT. `[ ]` are valid only inside an AREA[FieldName]value or RANGE[min, max] expre… |
| statusFilter | – | – | Filter by study status. Omit to count all statuses — an empty list is rejected, not treated as "no filter". Values: RECRUITING, COMPLETED, ACTIVE_NOT_RECRUITING, NOT_YET_RECRUITING, ENROLLING_BY_INVI… |
| titleQuery | string | – | Search within study titles and acronyms only. Matches Acronym, BriefTitle, and OfficialTitle. Plain words plus AND/OR/NOT. `[ ]` are valid only inside an AREA[FieldName]value or RANGE[min, max] expre… |
| Name | Type | Req | Description |
|---|---|---|---|
| error | object | – | Present when the call failed. Absent on success. |
| notice | string | – | Recovery guidance when totalCount is 0 — suggests how to broaden the query or filters. |
| searchCriteria | object | – | Echo of active query/filter criteria applied to this count, including sentinelFilterActive when the default unknown-enrollment exclusion is in effect. |
| totalCount | number | – | Total studies matching the query/filters. |
No examples provided.
clinicaltrials_get_study_record Clinicaltrials Get Study Record ~431
Fetch a single clinical trial study by NCT ID from ClinicalTrials.gov. Returns the full study record including protocol details, eligibility criteria, outcomes, arms, interventions, contacts, and locations. Optional locationLimit / outcomeLimit / referenceLimit / nearLocation parameters trim locations, outcomes, and references — original totals are preserved in `filtersApplied` only when a cap actually trims the set.
| Name | Type | Req | Description |
|---|---|---|---|
| locationLimit | integer | – | Optional cap on the number of locations returned. Omit for no cap (full upstream list); a value at or past the list length also returns every location. Pairs naturally with nearLocation for narrowing… |
| nctId | string | yes | NCT identifier — format `NCT` followed by 8 digits (e.g., `NCT03722472`). |
| nearLocation | object | – | Filter returned locations to those within radius of (lat, lon) and sort by distance. Adds distanceMi to each location. Locations without published coordinates are dropped — most US sites carry them;… |
| outcomeLimit | integer | – | Optional cap on the number of secondary and other outcomes returned. Omit for no cap (full upstream lists); a value at or past a list length also returns that whole list. Primary outcomes are never c… |
| referenceLimit | integer | – | Optional cap on the number of references returned. Omit for no cap (full upstream list); a value at or past the list length also returns every reference. Original total preserved in filtersApplied.to… |
| Name | Type | Req | Description |
|---|---|---|---|
| error | object | – | Present when the call failed. Absent on success. |
| filtersApplied | object | – | Metadata about the filtering applied to `study`. |
| resultsSummary | object | – | Compact counts of posted results, present when hasResults is true. The full resultsSection is intentionally omitted from this record-level tool — fetch it via clinicaltrials_get_study_results. |
| study | object | – | Full study record with caller-requested filters already applied to locations and outcomes. Top-level keys: protocolSection (identification, status, sponsor, conditions, design, arms/interventions, ou… |
No examples provided.
clinicaltrials_get_study_results Clinicaltrials Get Study Results ~1,129
Fetch clinical trial results data from ClinicalTrials.gov for completed studies — outcome measures with statistics, adverse events, participant flow, baseline characteristics, and results metadata (limitations & caveats, certain-agreement disclosure restrictions, results point of contact). Only available for studies where hasResults is true. Use clinicaltrials_search_studies first to find studies with results. Each call fetches up to 20 distinct NCT IDs and returns any further IDs in deferredNctIds for a follow-up call. A results-rich record can exceed 500KB per study in full mode — bound it with summary=true, narrower sections, or the outcomeLimit / adverseEventLimit caps; outcomeLimit / outcomeOffset also page summarized outcomes. A bounded list is resumable: outcomeOffset / seriousEventOffset / otherEventOffset start the next window, and each study's filtersApplied reports what was trimmed and the next offset for every list left short. A previous (alias) NCT ID resolves to its canonical study, named in canonicalNctId.
| Name | Type | Req | Description |
|---|---|---|---|
| adverseEventLimit | integer | – | Optional cap on the number of serious and other adverse events returned per study, applied to each list separately in upstream order. Omit for no cap (every event); a limit at or past a list’s length… |
| nctIds | – | yes | One or more NCT IDs — an empty list is rejected, and a repeated ID collapses to one results entry in first-occurrence order. A call fetches the first 20 distinct IDs; any further distinct IDs come ba… |
| otherEventOffset | integer | – | Optional index of the first other (non-serious) adverse event to return, in upstream order. Omit or 0 to start at the first. Pages independently of seriousEventOffset and pairs with adverseEventLimit… |
| outcomeLimit | integer | – | Optional cap on the number of outcome measures returned per study, taken in the order ClinicalTrials.gov publishes them. Omit for no cap (every measure); a limit at or past the list length returns th… |
| outcomeOffset | integer | – | Optional index of the first outcome measure to return, in the order ClinicalTrials.gov publishes them. Omit or 0 to start at the first. Pair with outcomeLimit to page a long list: each response repor… |
| sections | – | – | Filter which sections to return. Values: outcomes, adverseEvents, participantFlow, baseline, moreInfo. Omit for all sections — an empty list is rejected, not treated as omission. |
| seriousEventOffset | integer | – | Optional index of the first serious adverse event to return, in upstream order. Omit or 0 to start at the first. Pages independently of otherEventOffset — the two lists have uncorrelated lengths — an… |
| summary | boolean | – | Return condensed summaries instead of full data. Full mode renders every row and field on both output channels, so a large results set can exceed 500KB per study; summary mode typically cuts that to… |
| Name | Type | Req | Description |
|---|---|---|---|
| deferredNctIds | array | – | Requested NCT IDs past the per-call cap of 20 distinct IDs, normalized and deduplicated, in first-occurrence order. Not fetched — pass them as nctIds in a follow-up call. Absent when every requested… |
| error | object | – | Present when the call failed. Absent on success. |
| fetchErrors | array | – | Studies that could not be fetched. |
| results | array | – | Results per study. |
| studiesWithoutResults | array | – | NCT IDs that do not have results data. |
| truncated | boolean | – | True when a bound — a cap or an offset — trimmed a list on at least one study; absent when nothing was trimmed, matching filtersApplied one level down. Which study, which list, and where to resume is… |
No examples provided.
clinicaltrials_search_studies Clinicaltrials Search Studies ~2,139
Search for clinical trial studies from ClinicalTrials.gov. Supports full-text and field-specific queries, status/phase/geographic filters, pagination, sorting, and field selection. Returns a compact per-study index by default; pass the fields parameter to get specific leaves at full fidelity — full study records are ~70KB each.
| Name | Type | Req | Description |
|---|---|---|---|
| advancedFilter | string | – | Advanced filter using AREA[FieldName]value syntax. Examples: "AREA[StudyType]INTERVENTIONAL", "AREA[EnrollmentCount]RANGE[100, 1000]", "AREA[Phase]PHASE2 AND AREA[StudyType]INTERVENTIONAL", "(AREA[Ph… |
| conditionQuery | string | – | Condition/disease-specific search. E.g., "Type 2 Diabetes", "non-small cell lung cancer". Matches Condition, BriefTitle, OfficialTitle, ConditionMeshTerm, ConditionAncestorTerm, Keyword, and NCTId. C… |
| countTotal | boolean | – | Include total study count in response. Only computed on the first page. |
| fields | array | – | PascalCase leaf names to return; strongly recommended since full records are ~70KB. Omit for the compact index projection — an empty list is rejected, not treated as omission. A comma- or pipe-joined… |
| geoFilter | string | – | Geographic proximity filter. Format: distance(lat,lon,radius), where radius carries a `mi` or `km` suffix — e.g. "distance(47.6062,-122.3321,50mi)" for studies within 50 miles of Seattle. The suffix… |
| includeUnknownEnrollment | boolean | – | Include studies whose EnrollmentCount is the upstream "unknown" sentinel (99999999). Excluded by default — the sentinel pollutes RANGE[N, MAX] queries and EnrollmentCount:desc sorts. Set true for dat… |
| interventionQuery | string | – | Intervention/treatment search. E.g., "pembrolizumab", "cognitive behavioral therapy". Matches InterventionName, InterventionType, ArmGroupType, InterventionOtherName, BriefTitle, OfficialTitle, ArmGr… |
| locationQuery | string | – | Location search — city, state, country, or facility name. Matches LocationCity, LocationState, LocationCountry, LocationFacility, and LocationZip; a study matches when any of its sites does. Plain wo… |
| nctIds | – | – | Filter to specific NCT IDs for batch lookups. Omit to search every study — an empty list is rejected, not treated as "no filter". Repeated IDs collapse to one, first occurrence kept. One request carr… |
| outcomeQuery | string | – | Search within outcome measure fields. Matches PrimaryOutcomeMeasure, SecondaryOutcomeMeasure, OtherOutcomeMeasure, and OutcomeMeasureTitle, plus their description counterparts PrimaryOutcomeDescripti… |
| pageSize | integer | – | Results per page, 1–1000. A value above this server's per-page cap (200 unless the operator changed it) returns a page at the cap, reported in truncated/shown/cap with nextPageToken to continue. |
| pageToken | string | – | Pagination cursor: a previous response's nextPageToken, passed back unchanged with the same criteria. Tokens expire when ClinicalTrials.gov refreshes its data. |
| phaseFilter | – | – | Filter by trial phase. Omit to search all phases — an empty list is rejected, not treated as "no filter". Values: EARLY_PHASE1, PHASE1, PHASE2, PHASE3, PHASE4, NA. Case and spacing variants ("Phase 3… |
| query | string | – | General free-text search across all fields. Runs the 57-field relevance search ClinicalTrials.gov publishes for this parameter — NCTId, NCTIdAlias, OrgStudyId, SecondaryId, Acronym, BriefTitle, Offic… |
| sort | string | – | Sort order. Format: FieldName:asc or FieldName:desc. E.g., "LastUpdatePostDate:desc", "EnrollmentCount:desc". Max 2 fields comma-separated. For "largest trials" queries, pair EnrollmentCount:desc wit… |
| sponsorQuery | string | – | Sponsor/collaborator name search. Matches LeadSponsorName, CollaboratorName, and OrgFullName. Plain words plus AND/OR/NOT. `[ ]` are valid only inside an AREA[FieldName]value or RANGE[min, max] expre… |
| statusFilter | – | – | Filter by study status. Omit to search all statuses — an empty list is rejected, not treated as "no filter". Values: RECRUITING, COMPLETED, ACTIVE_NOT_RECRUITING, NOT_YET_RECRUITING, ENROLLING_BY_INV… |
| titleQuery | string | – | Search within study titles and acronyms only. Matches Acronym, BriefTitle, and OfficialTitle. Plain words plus AND/OR/NOT. `[ ]` are valid only inside an AREA[FieldName]value or RANGE[min, max] expre… |
| Name | Type | Req | Description |
|---|---|---|---|
| cap | integer | – | The server's per-page cap, served in place of the requested pageSize when truncated is true. |
| deferredNctIds | array | – | IDs from nctIds that did not fit in one ClinicalTrials.gov request beside the other parameters, deduplicated, in first-occurrence order. Not queried — studies and totalCount cover only the IDs that w… |
| error | object | – | Present when the call failed. Absent on success. |
| nextPageToken | string | – | Token for the next page. Absent when this response already carries every matching study; otherwise it mirrors the upstream cursor, which ClinicalTrials.gov emits whenever a page fills to pageSize — s… |
| notice | string | – | Recovery guidance when no studies matched — echoes the constraint and suggests how to broaden, and names nctIds as part of the unmatched criteria when an ID list was supplied. On a page cut to the se… |
| pageExhausted | boolean | – | True when this call supplied a pageToken and the continuation page came back empty — the walk is finished and no further pages exist. Absent on every other response, including an empty first page, wh… |
| requestedFields | array | – | Echo of the explicit fields parameter, with comma- or pipe-joined entries split into separate names and repeated names listed once — present only when the caller passed fields. Signals that studies c… |
| searchCriteria | object | – | Echo of active query/filter criteria applied to this search, including sentinelFilterActive when the default unknown-enrollment exclusion is in effect. Present on every response. |
| shown | integer | – | Studies on this page when truncated is true. |
| studies | array | – | Matching studies. By default each entry is a COMPACT index projection — nctId, briefTitle, overallStatus, phases, enrollmentCount, leadSponsor, conditions, hasResults, startDate and primaryCompletion… |
| totalCount | number | – | Total matching studies (first page only when countTotal=true). |
| truncated | boolean | – | True when pageSize was above the server's per-page cap and this page filled to the cap with a nextPageToken. Without a total to check against (countTotal: false, or a continuation page), that next pa… |
No examples provided.
How do I install the io.github.cyanheads/clinicaltrialsgov-mcp-server server?
io.github.cyanheads/clinicaltrialsgov-mcp-server is a hosted endpoint at https://clinicaltrials.caseyjhand.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · clinicaltrials.caseyjhand.com
claude mcp add --transport http cyanheads-clinicaltrialsgov-mcp-server 'https://clinicaltrials.caseyjhand.com/mcp'
What is the io.github.cyanheads/clinicaltrialsgov-mcp-server server?
io.github.cyanheads/clinicaltrialsgov-mcp-server is listed in the public MCP registry as io.github.cyanheads/clinicaltrialsgov-mcp-server. Search ClinicalTrials.gov: find studies, retrieve results, match patients to candidate trials. This page covers its hosted endpoint (https://clinicaltrials.caseyjhand.com/mcp).
Is the io.github.cyanheads/clinicaltrialsgov-mcp-server server safe to use?
io.github.cyanheads/clinicaltrialsgov-mcp-server scores 87 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the io.github.cyanheads/clinicaltrialsgov-mcp-server server expose?
io.github.cyanheads/clinicaltrialsgov-mcp-server exposes 7 tools: clinicaltrials_search_studies, clinicaltrials_get_study_record, clinicaltrials_get_study_count, clinicaltrials_get_field_values, clinicaltrials_get_field_definitions, and 2 more. Their descriptions and schemas cost roughly 6,555 tokens of context every time the server is loaded.
Does the io.github.cyanheads/clinicaltrialsgov-mcp-server server require authentication?
No. We connected to io.github.cyanheads/clinicaltrialsgov-mcp-server without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the io.github.cyanheads/clinicaltrialsgov-mcp-server server still maintained?
io.github.cyanheads/clinicaltrialsgov-mcp-server is still listed as active in the MCP registry. We last reached this channel on 6 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What did VerifyMCP test on the io.github.cyanheads/clinicaltrialsgov-mcp-server server?
VerifyMCP ran 13 checks on io.github.cyanheads/clinicaltrialsgov-mcp-server, covering TLS certificate, Authorization, HTTPS, HSTS header and 9 more. Supply Chain Security and Provenance & Transparency do not apply to a hosted endpoint, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.