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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Data access / search

ClinicalTrials.gov MCP by usefulapi

Search and read ClinicalTrials.gov studies, sites and outcomes.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
122 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
7

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 122 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name clinicaltrialsgov-mcp.

  • Pass
    Lists tools

    tools/list returned 7 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 122 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 122 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    30 of 30 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T23:33:20.73001Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using ClinicalTrials.gov MCP by usefulapi

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http clinicaltrials-gov-mcp-by-usefulapi https://clinicaltrialsgov.usefulapi.io/mcp

Capabilities

Tools 7

clinicaltrialsgov_count_studies

Return only the total NUMBER of studies matching a query, without fetching any records. Accepts the same query terms and filters as clinicaltrialsgov_search_studies (term, condition, intervention, title, location, sponsor, status, geoFilter, advanced). Returns { totalCount }. GET /studies with countTotal=true and pageSize=1.

Discovered
clinicaltrialsgov_get_api_version

Return the ClinicalTrials.gov API version and the timestamp of the underlying data snapshot: { apiVersion, dataTimestamp }. GET /version.

Discovered
clinicaltrialsgov_get_studies_stats

Return overall study-size statistics across the registry: { totalStudies, averageSizeBytes, percentiles, ranges, largestStudies }. Useful for understanding data volume. GET /stats/size.

Discovered
clinicaltrialsgov_get_study

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}.

Discovered
clinicaltrialsgov_get_study_metadata

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.

Discovered
clinicaltrialsgov_list_field_values

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.

Discovered
clinicaltrialsgov_search_studies

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.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected122 ms7