Agent Utils (x402)

by dev.workers.revenue-agent-jw.agent-utils-x402-production

ClinicalTrials.gov study by NCT ID

clinical_trial_study

Read-onlyIdempotent

ClinicalTrials.gov study lookup by NCT ID (official v2 API). Useful when an agent needs the facts of one trial. Returns titles, sponsor and collaborators, status and why stopped, key dates, phases, design, enrollment, conditions, interventions, primary outcomes, eligibility (ages, sex, criteria text), summary, site count, countries and up to 25 sites, plus results link, source URL and retrievedAt. Errors: 400 bad NCT ID, 404 not found. PAID: $0.001 USDC per call on Base via x402 (MCP transport: retry with params._meta["x402/payment"]). Same tool over plain HTTP: GET /v1/clinical-trials/study.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "nct": "<nct>"
    },
    "name": "clinical_trial_study"
  }
}

Input Schema

Name	Required	Description	Default
`nct`	Yes	NCT ID, e.g. NCT04368728

Schema Changelog

Changes observed during successful MCP inspections.

AddedNov 3, 2026

TDQS

A4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the readOnly/idempotent/openWorld annotations, the description discloses pricing ($0.001 USDC per call on Base via x402), the exact payment retry mechanism (params._meta["x402/payment"]), specific error codes (400 bad NCT ID, 404 not found), and an alternate HTTP endpoint. These are behaviorally decisive facts an agent cannot get from annotations or schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose is front-loaded in the first clause, then returns, errors, and payment in logical order with no filler sentences. The long return-field enumeration is dense but each item is informative, though it could be tightened into a summary.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description compensates by enumerating returned fields; it also covers error behavior, cost, payment flow, and an alternate transport. For a one-parameter read tool, nothing material is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single nct parameter is already documented with an example in the schema. The description adds only indirect meaning via the 400-bad-NCT-ID error, implying format validation, so the baseline of 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource ('ClinicalTrials.gov study lookup by NCT ID') and names the upstream API version, so the agent knows this is a single-record fetch. It does not explicitly contrast itself with the clinical_trials_search sibling, so differentiation is inferential rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

'Useful when an agent needs the facts of one trial' implies usage but gives no explicit when-not condition and never names the search sibling as the alternative for keyword/topic queries. An agent must infer that this tool is ID-only from the required nct parameter.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

All Agent Utils (x402) tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?