Upload business documents

This POST endpoint is used to upload documents for a business created with POST /business: a KYB report, articles of incorporation, a proof of address, and so on. <br> You must specify the business_token in the URL path. The caller must be the account that created the business, or the business itself using its own API key. <br> In the request body, include an array of documents. Each document requires a document_type, the original file_name (with its extension) and its Base64-encoded file_content; an optional description adds context, for other in particular. <br> Every document is validated and virus-scanned before any is stored, so a rejected document rejects the whole request and nothing is written. <br> A document may be at most 4,500,000 bytes once decoded and a request may carry at most 10 documents; the whole request must also stay under the 6 MB API limit (Base64 adds a third to each file), so larger sets go in several requests to POST /business/{business_token}/documents. <br> The response lists the documents stored, in request order, each with its document_token. A document that could not be stored is left out: compare the response with what you sent and resend what is missing. Uploads only add documents; nothing already on file is replaced.