Use this endpoint when you already have information that you want to send for a transaction before 1Money asks for it. You do not need to find an RFI case first: we create one when necessary or add the information to an existing case that still accepts submissions.

The transaction must belong to this customer and must not be in a final state.

The endpoint accepts two representations and dispatches on the Content-Type header: application/json for TEXT and multipart/form-data for FILE. Any other Content-Type is rejected.

Send a TEXT response

{
  "subject": { "type": "TRANSACTION", "id": "<transaction_id>" },
  "submission": { "type": "TEXT", "text": "Funds originate from invoice INV-2026-001." }
}

text is required, nonblank, and at most 2,560 UTF-8 bytes.

Send a FILE response

Use multipart/form-data and send the original file bytes. Do not Base64-encode the file. Send each part once; field names and enum values are case-sensitive.

Sign the request

With HMAC authentication, sign a TEXT request with the standard JSON body-signing flow. For a FILE request, choose one multipart signing mode:

• Sign the complete encoded multipart body when your client exposes the final bytes.
• Use X-OM-Content-SHA256: UNSIGNED-PAYLOAD when your client builds and sends the form internally.

See Signing multipart requests for both canonical strings, their security properties, and examples.

Idempotency

Idempotency-Key is required. We return 201 when the request creates the related case and 200 when we reuse an existing case. An exact retry returns the current response for the original request with 200; reusing the key for different content returns 409.