# ClinicalTrials.gov Study Search by Condition

> ClinicalTrials.gov Study Search by Condition is a paid API for AI agents from foundry-par007-machine-revenue-mainnet.inference-chip-index.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Returns recently updated ClinicalTrials.gov study identifiers, titles, and registry status for a given medical condition, with registry processing date.

## Facts

- Endpoint: POST https://foundry-par007-machine-revenue-mainnet.inference-chip-index.workers.dev/v2/official/clinicaltrials-search
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/clinicaltrials-gov-study-search-by-condition-f7963f44
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TqWRogb2iIjkL-KTkEL3s

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability clinicaltrials-gov-study-search-by-condition-f7963f44 -d '<json body>'
```

Example prompt: Search ClinicalTrials.gov for up to 10 recently updated studies on Parkinson's disease and give me their NCT identifiers, titles, and current registry status.

## When to prefer this

Choose this endpoint when you need to discover multiple clinical trial registry entries for a specific medical condition from ClinicalTrials.gov, especially when you need recently updated studies with their NCT identifiers and status. Prefer this over the NCT resolver sibling when you don't yet have specific NCT IDs and need to search by condition name. Best for research, patient advocacy, competitive intelligence, or clinical landscape surveys where breadth across trials matters more than deep detail on one trial.

## Known failure modes

- Condition string too short (under 2 characters) or too long (over 120 characters) returns a validation error
- Limit outside 1-20 range returns a validation error
- No matching studies found returns an empty normalizedResult array
- ClinicalTrials.gov upstream API unavailable may return a service error or stale cache
- Ambiguous or misspelled condition name may return zero results or unrelated studies
- Payment not included or insufficient USDC triggers x402 payment required response

## How this service works

Pay-per-request evidence and data tools: CSV validation and reconciliation, DNS/email configuration evidence, and bounded official weather, earthquake, vehicle, company and study records. Exact USDC prices, explicit JSON contracts and source provenance. No mailbox, ownership, medical or safety guarantees.

## Output

Returns a JSON object containing the condition queried, a list of matching ClinicalTrials.gov studies (each with NCT identifier, title, and registry status), the registry processing date, source attribution, freshness metadata including retrieval timestamp, and provenance details including licensing terms and upstream API documentation URL.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "limit": {
   "type": "integer",
   "default": 10,
   "maximum": 20,
   "minimum": 1
  },
  "condition": {
   "type": "string",
   "maxLength": 120,
   "minLength": 2
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "route": "clinicaltrials-search",
  "result": {
   "query": {
    "limit": 5,
    "condition": "asthma"
   },
   "source": "ClinicalTrials.gov",
   "freshness": {
    "state": "CURRENT_RETRIEVAL",
    "retrievedAt": "2026-09-06T00:00:00Z",
    "cacheAgeSeconds": 0,
    "maximumCacheSeconds": 0,
    "recordAgeIsNotRetrievalAge": true
   },
   "sourceUrl": "https://clinicaltrials.gov",
   "observedAt": "2026-09-06T00:00:00Z",
   "provenance": {
    "license": "ClinicalTrials.gov terms; bounded factual study metadata only",
    "termsUrl": "https://clinicaltrials.gov/about-site/terms-conditions",
    "truncated": false,
    "attribution": "ClinicalTrials.gov, US National Library of Medicine",
    "limitations": [
     "Synthetic example only; identifiers and null values illustrate fields, not a live observation."
    ],
    "modifications": "Selected factual fields, normalized names and bounded result count; no source ownership claimed.",
    "upstreamCalls": 1,
    "documentationUrl": "https://clinicaltrials.gov/data-api/api"
   },
   "sourceUpdatedAt": null,
   "normalizedResult": [
    {
     "nctId": "NCT00110383",
     "title": null,
     "phases": [],
     "sourceUrl": "https://clinicaltrials.gov/study/NCT00110383",
     "startDate": null,
     "studyType": null,
     "overallStatus": null,
     "completionDate": null,
     "lastUpdatePostDate": null
    }
   ],
   "sourceProcessedAt": null,
   "rawSourceIdentifiers": []
  },
  "observed_at": "2026-09-06T00:00:00Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/clinicaltrials-gov-study-search-by-condition-f7963f44/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from foundry-par007-machine-revenue-mainnet.inference-chip-index.workers.dev](https://www.zero.xyz/host/foundry-par007-machine-revenue-mainnet.inference-chip-index.workers.dev/llms.txt)