io.usefulapi/clinicaltrialsgov
REMOTE · CLINICALTRIALSGOV.USEFULAPI.IO · SCANNED OCT 4
Search and read ClinicalTrials.gov studies, sites and outcomes.
Available components
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 Security46
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not yet verified: we couldn't confirm whether this endpoint requires it. View diagnostics → Unverified
- HTTPS enforcement could not be verified: the plaintext port answered with HTTP 429, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability0
- Transport check failed: declared streamable-http, but the endpoint returned HTTP 429. See how to fix → View diagnostics → Fail
Schema Quality & AI Usability0
- Schema not yet verified: we couldn't read the endpoint's schema, or could read only part of its tool list.Unverified
Stability & Change Management0
- Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage0
- Tool coverage not yet verified: we couldn't read the endpoint's tools, or could read only part of the list.Unverified
Tool Safety0
- Tool safety not yet verified: we couldn't read the endpoint's tools, or could read only part of the list.Unverified
Capabilities0
- Capabilities not yet verified: we couldn't read the endpoint's capabilities.Unverified
Unverified: 5 categories
Categories scored 0 because we could not verify them: authentication we do not have, an unreachable endpoint, or not enough scan history. We only credit what we can confirm.
How do I install the io.usefulapi/clinicaltrialsgov MCP server?
io.usefulapi/clinicaltrialsgov is a hosted endpoint at https://clinicaltrialsgov.usefulapi.io/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 · clinicaltrialsgov.usefulapi.io
claude mcp add --transport http io-usefulapi-clinicaltrialsgov 'https://clinicaltrialsgov.usefulapi.io/mcp'
{
"mcpServers": {
"io-usefulapi-clinicaltrialsgov": {
"url": "https://clinicaltrialsgov.usefulapi.io/mcp"
}
}
} {
"servers": {
"io-usefulapi-clinicaltrialsgov": {
"type": "http",
"url": "https://clinicaltrialsgov.usefulapi.io/mcp"
}
}
} [mcp_servers.io-usefulapi-clinicaltrialsgov] url = "https://clinicaltrialsgov.usefulapi.io/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"io-usefulapi-clinicaltrialsgov": {
"type": "remote",
"url": "https://clinicaltrialsgov.usefulapi.io/mcp",
"enabled": true
}
}
} openclaw mcp add io-usefulapi-clinicaltrialsgov --url 'https://clinicaltrialsgov.usefulapi.io/mcp' --transport streamable-http
mcp_servers:
io-usefulapi-clinicaltrialsgov:
url: "https://clinicaltrialsgov.usefulapi.io/mcp" {
"McpServers": {
"io-usefulapi-clinicaltrialsgov": {
"Transport": "http",
"Url": "https://clinicaltrialsgov.usefulapi.io/mcp"
}
}
} assistant mcp add io-usefulapi-clinicaltrialsgov -t streamable-http -u 'https://clinicaltrialsgov.usefulapi.io/mcp'
{
"mcpServers": {
"io-usefulapi-clinicaltrialsgov": {
"type": "http",
"url": "https://clinicaltrialsgov.usefulapi.io/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
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.
- 3 Oct 26 −57
- Endpoint reachability: reachable → not serving MCP ▼ security
- Tool safety: pass → unverified ▼ security
- HTTPS: pass → unverified ▼ security
- Authorization: pass → unverified ▼ security
- Transport: pass → fail ▼ security
- Capabilities: fail → unverified ▼ functional
- Tool coverage: 100 → unverified ▼ functional
- 2 Oct 26 +42
- Authorization: unverified → pass ▲ security
- Injection markers: unverified → pass ▲ security
- First check of Judged manipulation: pass security
- First check of Authorization: partial security
- MCP protocol: unverified → fail ▼ functional
- Tool coverage: unverified → 100 ▲ functional
- First check of Schema quality: fail functional
- First check of Schema quality: excellent functional
- First check of Destructive annotations: pass functional
- First check of Schema quality: fail functional
- First check of Tool coverage: 100 functional
- 1 Oct 26 +15
- Transport: unverified → pass ▲ security
- HTTPS: unverified → pass ▲ security
- Authorization: Authorisation not fully verified: no authorisation is required to connect, but we couldn't read the whole tool list to see what that exposes. security
- 30 Sept 26 0
- Transport: fail → unverified ▼ security
- 29 Sept 26 18
First indexed and scored.
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 4 Oct 2026 · Probed https://clinicaltrialsgov.usefulapi.io/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=usefulapi.io | CN=WE1,O=Google Trust Services,C=US | 13 Sept 2026 | 12 Dec 2026 | ECDSA 256 | ECDSA-SHA256 | d9be3287b0fde9630e825ba1f79bff3f |
| SANs: usefulapi.io, *.usefulapi.io | ||||||
| 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 insecure
Validation of clinicaltrialsgov.usefulapi.io. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| io. | present | 57355 | 8 | Verified |
| usefulapi.io. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication Inconclusive
We could not reach the endpoint well enough to judge its authorisation posture.
| Result | Inconclusive |
|---|---|
| HTTP status | 429 |
| Header | Value |
|---|---|
| x-frame-options | SAMEORIGIN |
| referrer-policy | same-origin |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://clinicaltrialsgov.usefulapi.io/mcp | HTTP error | 429 | |
| http (plaintext) | http://clinicaltrialsgov.usefulapi.io/mcp | Inconclusive | 429 |
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 →
count_studies Count matching clinical trials ~355
Return only the total NUMBER of studies matching a query, without fetching any records. Accepts the same query terms and filters as search_studies (term, condition, intervention, title, location, sponsor, status, geoFilter, advanced). Returns { totalCount }. GET /studies with countTotal=true and pageSize=1.
| Name | Type | Req | Description |
|---|---|---|---|
| advanced | string | – | Advanced Essie expression applied as an additional filter (maps to filter.advanced). |
| condition | string | – | Disease / condition to match (maps to query.cond), e.g. 'diabetes'. |
| geoFilter | string | – | Geo filter as a raw geo-function string (maps to filter.geo), e.g. 'distance(39.0027,-77.1,50mi)'. |
| intervention | string | – | Treatment / drug / intervention to match (maps to query.intr). |
| location | string | – | Study location text, e.g. a city/state/country (maps to query.locn). |
| sponsor | string | – | Sponsor / collaborator name (maps to query.spons). |
| status | array | – | Filter by overall recruitment status (maps to filter.overallStatus). One or more of: ACTIVE_NOT_RECRUITING, COMPLETED, ENROLLING_BY_INVITATION, NOT_YET_RECRUITING, RECRUITING, SUSPENDED, TERMINATED,… |
| term | string | – | General full-text 'other terms' query (maps to query.term). |
| title | string | – | Words in the study title (maps to query.titles). |
No output schema declared.
No examples provided.
get_api_version Get the ClinicalTrials.gov API version ~36
Return the ClinicalTrials.gov API version and the timestamp of the underlying data snapshot: { apiVersion, dataTimestamp }. GET /version.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
get_studies_stats Get study size statistics ~47
Return overall study-size statistics across the registry: { totalStudies, averageSizeBytes, percentiles, ranges, largestStudies }. Useful for understanding data volume. GET /stats/size.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
get_study Get a clinical trial by NCT ID ~145
Fetch a single ClinicalTrials.gov study by its NCT id (format NCT######## — the letters 'NCT' followed by digits, e.g. NCT00841061). Returns the full study object { protocolSection, derivedSection?, hasResults? }. Use `fields` to return only specific fields/modules. GET /studies/{nctId}.
| Name | Type | Req | Description |
|---|---|---|---|
| fields | array | – | Fields or modules to return, e.g. ['protocolSection.identificationModule','protocolSection.statusModule']. Omit for the full record. |
| nctId | string | yes | The study's NCT id, format NCT######## (e.g. NCT00841061). |
No output schema declared.
No examples provided.
get_study_metadata Get the study data-model (field tree) ~110
Return the ClinicalTrials.gov study data model as a tree of module nodes (each with name/title/type/children). Use this to explore what fields/modules exist and their nesting, to build `fields` selections or `sort`/filter expressions. GET /studies/metadata.
| Name | Type | Req | Description |
|---|---|---|---|
| includeHistoricOnly | boolean | – | Include fields that exist only in historic study versions. |
| includeIndexedOnly | boolean | – | Include fields that are indexed-only (searchable but not part of the main data model). |
No output schema declared.
No examples provided.
list_field_values List value statistics for study fields ~126
Discover valid values / enums for one or more study fields. Returns per-field value statistics — for each field: its type, unique-value count and topValues [{value, studiesCount}]. Great for finding valid enum values (e.g. OverallStatus, Phase) before building a filter. GET /stats/field/values.
| Name | Type | Req | Description |
|---|---|---|---|
| fields | array | yes | Field names to get value statistics for, e.g. ['OverallStatus','Phase']. |
| types | array | – | Restrict to fields of these value types (ENUM, STRING, DATE, INTEGER, NUMBER, BOOLEAN). |
No output schema declared.
No examples provided.
search_studies Search clinical trials (ClinicalTrials.gov) ~594
Search the ClinicalTrials.gov v2 study registry. Provide any combination of query terms (condition, intervention, title, location, sponsor, general term) — multiple query.* terms are ANDed together — plus optional filters (status, geo, advanced Essie expression, explicit NCT ids). Returns { totalCount?, studies: [...], nextPageToken? }. Use `fields` to trim the response to specific fields/modules, `sort` to order (e.g. '@relevance', 'LastUpdatePostDate:desc', 'EnrollmentCount:desc'), and pageSize/pageToken to page. GET /studies.
| Name | Type | Req | Description |
|---|---|---|---|
| advanced | string | – | Advanced Essie expression applied as an additional filter (maps to filter.advanced). |
| condition | string | – | Disease / condition to match (maps to query.cond), e.g. 'diabetes'. |
| countTotal | boolean | – | Include the total number of matching studies (totalCount) on the first page. |
| fields | array | – | Fields or modules to return, e.g. ['NCTId','BriefTitle','OverallStatus'] or ['protocolSection.identificationModule']. Omit to return full study records. |
| geoFilter | string | – | Geo filter as a raw geo-function string (maps to filter.geo), e.g. 'distance(39.0027,-77.1,50mi)'. |
| ids | array | – | Restrict to these NCT ids (maps to filter.ids), e.g. ['NCT00841061']. |
| intervention | string | – | Treatment / drug / intervention to match (maps to query.intr). |
| location | string | – | Study location text, e.g. a city/state/country (maps to query.locn). |
| pageSize | integer | – | Number of studies per page (1–1000; API default 10). |
| pageToken | string | – | Opaque token from a previous response's nextPageToken, to fetch the next page. |
| sort | string | – | Sort order, e.g. '@relevance', 'LastUpdatePostDate:desc', 'EnrollmentCount:desc', 'StudyFirstPostDate:desc'. |
| sponsor | string | – | Sponsor / collaborator name (maps to query.spons). |
| status | array | – | Filter by overall recruitment status (maps to filter.overallStatus). One or more of: ACTIVE_NOT_RECRUITING, COMPLETED, ENROLLING_BY_INVITATION, NOT_YET_RECRUITING, RECRUITING, SUSPENDED, TERMINATED,… |
| term | string | – | General full-text 'other terms' query (maps to query.term). |
| title | string | – | Words in the study title (maps to query.titles). |
No output schema declared.
No examples provided.
What is the io.usefulapi/clinicaltrialsgov MCP server?
io.usefulapi/clinicaltrialsgov is an MCP server listed in the public MCP registry as io.usefulapi/clinicaltrialsgov. Search and read ClinicalTrials.gov studies, sites and outcomes. This page covers its hosted endpoint (https://clinicaltrialsgov.usefulapi.io/mcp).
Is the io.usefulapi/clinicaltrialsgov MCP server safe to use?
io.usefulapi/clinicaltrialsgov scores 18 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.usefulapi/clinicaltrialsgov MCP server expose?
io.usefulapi/clinicaltrialsgov exposes 7 tools: search_studies, get_study, count_studies, list_field_values, get_study_metadata, and 2 more. Their descriptions and schemas cost roughly 1,413 tokens of context every time the server is loaded.
Does the io.usefulapi/clinicaltrialsgov MCP server require authentication?
Its publisher declares no required credentials for io.usefulapi/clinicaltrialsgov. We have not been able to confirm that against the live endpoint, and a server can require authorisation without declaring it here.
Is the io.usefulapi/clinicaltrialsgov MCP server still maintained?
io.usefulapi/clinicaltrialsgov is still listed as active in the MCP registry. We last reached this channel on 4 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.