POST /v2/transactions is polymorphic. Specify --type to see the full schema:

  account-interest-transaction
  bond-coupon-transaction
  bond-redemption-transaction
  bond-trade-transaction
  cash-transfer-transaction
  dividend-transaction
  equity-trade-transaction
  fee-transaction
  futures-trade-transaction
  futures-execution-transaction
  fx-spot-transaction
  index-linked-bond-coupon-transaction
  index-linked-bond-redemption-transaction
  index-linked-bond-trade-transaction
  private-market-fund-distribution-transaction
  private-market-fund-drawdown-transaction
  refund-transaction
  zero-coupon-bond-trade-transaction

These types are auto-created by the system and cannot be POSTed:
  loan-transaction
  fx-forward-cash-settlement-transaction
  fx-forward-physical-delivery-transaction

Example: aleta api --spec POST /v2/transactions --type bond-trade-transaction