{"openapi":"3.1.0","info":{"title":"POST /api/v1/invoices/{invoice_id}/payments","version":"1.0.0","description":"Add payment to invoice"},"servers":[{"url":"https://api.ondayzero.com","description":"Production"}],"paths":{"/api/v1/invoices/{invoice_id}/payments":{"post":{"tags":["invoices"],"summary":"Add payment to invoice","description":"Link a bank transaction as payment against an invoice. Supports split payments (one transaction paying multiple invoices) and partial payments (multiple transactions paying one invoice).","operationId":"create_invoice_payment_api_v1_invoices__invoice_id__payments_post","parameters":[{"name":"invoice_id","in":"path","required":true,"schema":{"type":"string","format":"uuid","title":"Invoice Id"}},{"name":"authorization","in":"header","required":false,"schema":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"Authorization"}},{"name":"x-business-id","in":"header","required":false,"schema":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"X-Business-Id"}}],"requestBody":{"required":true,"content":{"application/json":{"schema":{"$ref":"#/components/schemas/InvoicePaymentRequest"}}}},"responses":{"201":{"description":"Successful Response","content":{"application/json":{"schema":{"$ref":"#/components/schemas/InvoicePaymentResponse"}}}},"400":{"description":"Bad Request - Invalid input","content":{"application/json":{"example":{"detail":"Invalid request parameters"}}}},"401":{"description":"Unauthorized - Authentication required","content":{"application/json":{"example":{"detail":"Not authenticated"}}}},"403":{"description":"Forbidden - Insufficient permissions","content":{"application/json":{"example":{"detail":"Not enough permissions"}}}},"404":{"description":"Not Found - Resource does not exist","content":{"application/json":{"example":{"detail":"Resource not found"}}}},"422":{"description":"Validation Error","content":{"application/json":{"schema":{"$ref":"#/components/schemas/HTTPValidationError"}}}}}}}},"components":{"schemas":{"HTTPValidationError":{"properties":{"detail":{"items":{"$ref":"#/components/schemas/ValidationError"},"type":"array","title":"Detail"}},"type":"object","title":"HTTPValidationError"},"InvoicePaymentRequest":{"properties":{"transaction_id":{"type":"string","title":"Transaction Id","description":"UUID of the bank transaction representing the payment."},"amount":{"type":"integer","exclusiveMinimum":0.0,"title":"Amount","description":"Payment amount in cents allocated to this invoice.  Must be > 0 and <= the remaining unallocated amount on the transaction.  Overpayments (exceeding the invoice balance) are permitted."},"paid_on":{"anyOf":[{"type":"string","format":"date-time"},{"type":"null"}],"title":"Paid On","description":"Override payment date (ISO 8601).  Defaults to the transaction datetime if omitted."}},"type":"object","required":["transaction_id","amount"],"title":"InvoicePaymentRequest","description":"Request schema for linking a bank transaction as payment against an invoice.\n\nSupports split payments: a single transaction can pay multiple invoices\nby creating separate payment records with different allocated amounts.\n\nExample — a $200 bank deposit paying two invoices::\n\n    POST /invoices/{inv_1}/payments  {\"transaction_id\": \"txn_abc\", \"amount\": 12000}\n    POST /invoices/{inv_2}/payments  {\"transaction_id\": \"txn_abc\", \"amount\": 8000}","example":{"amount":12000,"transaction_id":"019ab37c-txn1-7000-8000-000000000001"}},"InvoicePaymentResponse":{"properties":{"id":{"type":"string","title":"Id","description":"Payment record UUID."},"invoice_id":{"type":"string","title":"Invoice Id","description":"UUID of the invoice being paid."},"transaction_id":{"type":"string","title":"Transaction Id","description":"UUID of the bank transaction."},"amount":{"type":"integer","title":"Amount","description":"Allocated payment amount in cents."},"currency":{"type":"string","title":"Currency","description":"Currency (USD, CAD, AUD, EUR, or GBP).","default":"USD"},"paid_on":{"type":"string","format":"date-time","title":"Paid On","description":"Effective payment date."},"created_at":{"type":"string","format":"date-time","title":"Created At","description":"Record creation timestamp."},"updated_at":{"type":"string","format":"date-time","title":"Updated At","description":"Last update timestamp."},"business_id":{"type":"string","title":"Business Id","description":"Business UUID."},"transaction":{"anyOf":[{"$ref":"#/components/schemas/InvoicePaymentTransactionSummary"},{"type":"null"}],"description":"Linked bank transaction summary. Included when listing payments."}},"type":"object","required":["id","invoice_id","transaction_id","amount","paid_on","created_at","updated_at","business_id"],"title":"InvoicePaymentResponse","description":"Response schema for an invoice payment record.\n\nRepresents a payment made against an invoice, linking to the bank\ntransaction with a specific allocated amount.","example":{"amount":12000,"business_id":"019ab37c-bus1-7000-8000-000000000001","created_at":"2026-02-10T12:00:00Z","currency":"USD","id":"019ab37c-pay1-7000-8000-000000000001","invoice_id":"019ab37c-inv1-7000-8000-000000000001","paid_on":"2026-02-10T00:00:00Z","transaction":{"amount":12000,"counterparty":"Acme Corp","currency":"USD","datetime":"2026-02-10T00:00:00Z","description":"Invoice payment","id":"019ab37c-txn1-7000-8000-000000000001","ledger_id":"019ab37c-led1-7000-8000-000000000001"},"transaction_id":"019ab37c-txn1-7000-8000-000000000001","updated_at":"2026-02-10T12:00:00Z"}},"InvoicePaymentTransactionSummary":{"properties":{"id":{"type":"string","title":"Id","description":"Transaction UUID."},"amount":{"type":"integer","title":"Amount","description":"Transaction amount in cents. Positive = deposit, negative = withdrawal."},"currency":{"type":"string","title":"Currency","description":"Currency code (USD, CAD, AUD, EUR, or GBP).","default":"USD"},"datetime":{"type":"string","format":"date","title":"Datetime","description":"The date the transaction occurred."},"counterparty":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"Counterparty","description":"Clean counterparty/merchant name."},"description":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"Description","description":"Transaction memo/description."},"ledger_id":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"Ledger Id","description":"Bank account (ledger) UUID."}},"type":"object","required":["id","amount","datetime"],"title":"InvoicePaymentTransactionSummary","description":"Lightweight transaction summary embedded in invoice payment responses.\n\nContains the key fields needed to display the linked bank transaction\nwithout pulling the full TransactionResponse (journal entries, threads, etc.)."},"ValidationError":{"properties":{"loc":{"items":{"anyOf":[{"type":"string"},{"type":"integer"}]},"type":"array","title":"Location"},"msg":{"type":"string","title":"Message"},"type":{"type":"string","title":"Error Type"},"input":{"title":"Input"},"ctx":{"type":"object","title":"Context"}},"type":"object","required":["loc","msg","type"],"title":"ValidationError"}},"securitySchemes":{"BearerAuth":{"type":"http","scheme":"bearer","bearerFormat":"API Token","description":"API token authentication. Format: `Bearer dz_...`"}}},"security":[{"BearerAuth":[]}]}