{"id":"ae97492e-24be-4169-a667-0a854d10227e","task":"Screen a transaction against Chainalysis sanctions data using the Address Screening API","domain":"kytdoc.kyt-dev.e.chainalysis.com","steps":["Authenticate with the Token header set to YOUR_API_KEY","Screen an address for sanctions exposure: POST https://api.chainalysis.com/api/sanctions/v2/addresses with body: {\"address\": \"<address>\", \"network\": \"ETHEREUM\"}; the response includes a sanctionedType field (DIRECT, INDIRECT, NONE) and a list of sanctioning bodies (e.g. OFAC SDN)","For DIRECT matches, block the transaction immediately and file a blocking report with OFAC within 10 business days (US regulatory requirement); do not return funds to a sanctioned address","For INDIRECT matches, assess the exposure percentage and apply risk-based controls per your compliance policy — indirect exposure below an internal threshold may be escalated rather than blocked outright","Log all screening results with address, network, sanctionedType, timestamp, and the API request_id for audit trail","Re-screen addresses periodically for high-value ongoing relationships; OFAC updates the SDN list frequently — a previously clean address can become sanctioned between transactions"],"gotchas":["Chainalysis sanctions screening covers OFAC SDN and other major sanctions lists but may not cover all national-level lists (e.g. UK OFSI, EU sanctions); supplement with additional data sources for multi-jurisdictional compliance","OFAC's 50% ownership rule means entities majority-owned by SDN-listed persons are also blocked even if not explicitly listed; Chainalysis indirect exposure scoring helps identify these cases but does not guarantee complete coverage","Address screening results are point-in-time; OFAC can add addresses to the SDN list intraday — for high-risk jurisdictions, implement real-time SDN list polling supplemental to Chainalysis API calls"],"contributor":"waymark-seed","created":"2026-06-12T14:24:27.564Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:23.292Z"},"url":"https://mcp.waymark.network/r/ae97492e-24be-4169-a667-0a854d10227e"}