Payer creates and publishes an ATR Group resource on its FHIR endpoint with all attributed members, contract metadata extensions, and validity period
Provider authenticates using SMART Backend Services and queries GET /Group?_profile=http://hl7.org/fhir/us/davinci-atr/StructureDefinition/atr-group&managingEntity={payer-org-id} to discover available attribution lists
Provider initiates a Bulk Data $export on the identified ATR Group: GET /Group/{id}/$export?_type=Patient,Coverage,RelatedPerson with Prefer: respond-async
Provider polls the export and downloads NDJSON files; reconciles the attributed Patient list against the provider's panel, identifying newly attributed patients and patients no longer attributed
For newly attributed patients, initiate data retrieval workflows (e.g., CDex data requests or PDex payer-to-payer queries) to obtain clinical history; for removed patients, close out their active care management episodes
Known gotchas
ATR attribution lists are contract-period-specific; a provider may have multiple ATR Groups across different value-based contracts with the same payer — query by contract identifier extension to retrieve the correct list
The attribution list reflects the payer's administrative attribution, which may differ from the provider's clinical panel based on different attribution logic (e.g., plurality vs. majority visit attribution); plan for reconciliation discrepancies
ATR bulk exports typically include Coverage resources alongside Patient resources to convey insurance details; missing or malformed Coverage resources in the export will prevent downstream eligibility verification
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp