{"uid":"cap_PdOKoPDATDu-BVi8Pao7Y","slug":"trialscope-clinical-trial-change-delta-lookup-182206b1","name":"TrialScope — Clinical Trial Change-Delta Lookup","description":"Per-call clinical trial search, study dossiers, and change-deltas from ClinicalTrials.gov. Paid per call via the x402 protocol (USDC); unpaid requests return HTTP 402 with payment terms in the PAYMENT-REQUIRED header. Terms of service: GET /terms (free).","url":"https://x402-trialscope.onrender.com/delta?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["snapshotId","nctId"],"properties":{"nctId":{"type":"string","description":"NCT id that was in the snapshot"},"snapshotId":{"type":"string","description":"Snapshot id from POST /snapshot"}}}},"additionalProperties":false}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_2sp5fD1RTbvrwurmC8U5C","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Retrieves the field-level changes between a stored snapshot and the current ClinicalTrials.gov record for a specific trial, revealing what has changed since the snapshot was taken.","exampleAgentPrompt":"Show me what changed in clinical trial NCT04280705 since snapshot 'snap_abc123' — I want to see every field that was updated.","exampleUseCases":[{"title":"Track eligibility criteria changes","prompt":"Has anything changed in the eligibility criteria for clinical trial NCT04280705 since I took snapshot snap_abc123 last week? Show me the exact field differences."},{"title":"Monitor trial status updates","prompt":"Check if the enrollment status or phase for trial NCT03745183 has changed since snapshot snap_def456 — I need to know if it moved from recruiting to completed."},{"title":"Audit protocol amendments","prompt":"Pull the change-delta for NCT02678520 against snapshot snap_ghi789 so I can audit what protocol amendments were made since our last review."}],"resultDescription":"Returns a structured diff object showing field-level changes between the stored snapshot and the current ClinicalTrials.gov record for the specified NCT ID, including which fields were added, removed, or modified and their old vs. new values.","failureModes":["HTTP 402 returned if payment not provided via x402 protocol — caller must pay $0.02 USDC per call","Invalid or expired snapshotId returns an error indicating the snapshot was not found","Invalid nctId format returns a validation error","NCT ID not present in the snapshot returns a mismatch error","Network or upstream ClinicalTrials.gov API unavailability may cause 503 responses"],"whenToPreferThis":"Choose this endpoint when you have a previously created snapshot (via POST /snapshot) and need to see exactly what changed in a specific trial record since that snapshot was taken. It is purpose-built for change-detection workflows on ClinicalTrials.gov data, unlike a fresh search or full dossier fetch. Use it when you need a diff, not a full record pull.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T18:31:19.619Z","isFirstParty":false,"canonicalSlug":"trialscope-clinical-trial-change-delta-lookup-182206b1"}