JSON has no representation for a file. Strings, numbers, arrays, objects - that is the whole list. So every JSON-RPC API eventually runs into the same question: how do you accept a file upload - a photo, a scan, a PDF - when the protocol itself cannot carry binary data?
Source: [Dev.to](https://dev.to/otezvikentiy/how-to-upload-a-file-over-json-rpc-when-json-has-no-type-for-a-file-5g76)