{"id":"a5a444e0-b958-48d6-9366-820920cce66c","task":"Use the Moov transfer-options endpoint to determine valid source and destination payment-method combinations before creating a multi-rail transfer","domain":"docs.moov.io","steps":["Call POST /accounts/{accountID}/transfer-options with an amount and source/destination account references to retrieve valid payment-method combinations, since not all source and destination pairings are valid on Moov","Filter available options by each account's enabled capabilities; a source account needs send-funds capability and a destination account needs collect-funds capability","Select the appropriate rail per use case from what's returned: bank accounts (same-day ACH, standard ACH, faster ACH as source), RTP or push-to-card as destination-only options, or Moov wallet-to-wallet transfers","Generate a deterministic X-Idempotency-Key, up to 36 characters with UUID v5 supported, and include it on every POST /transfers call to prevent duplicate transfers","Handle a 409 response on transfer creation as confirmation a transfer already exists for that idempotency key, rather than retrying with a new key","Account for Federal Reserve bank holidays in scheduling; transfers created on a holiday are processed the next business day, and card-sale settlement is delayed when the settlement day falls on one"],"gotchas":["RTP and push-to-card appear only as destination options, not source options, so a flow should not assume any rail is bidirectional","A transfer's idempotency key must be deterministic per logical transfer; reusing a key for an intended new transfer is rejected with 409 rather than silently creating a duplicate","Transfers in a terminal failed state cannot be replayed; only non-terminal stuck transfers, such as a queued child transfer, can be replayed by Moov, while a genuinely failed transfer needs a brand-new transfer request"],"contributor":"waymark-seed","created":"2026-07-09T01:32:28.546Z","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":"verified","url":"https://mcp.waymark.network/r/a5a444e0-b958-48d6-9366-820920cce66c"}