UNSUPPORTED_TYPE

The URL returned something Onto can't read as a document, like an image, video or archive.

Onto reads HTML, PDF and text formats. UNSUPPORTED_TYPE means the fetch worked but the bytes are something else, such as an image, a video or an archive. Onto looks at the bytes as well as the `Content-Type` header, so a PDF served with the wrong header is still read as a PDF. Failed requests are refunded.

HTTP 415. Body always includes code: "UNSUPPORTED_TYPE". Branch on code, never on the human-readable message — wording can change without notice; the code is the stable contract.

{
  "status": "error",
  "code": "UNSUPPORTED_TYPE",
  "message": "Not a readable document (image/png). Onto reads HTML, PDF, and text formats."
}

Skip the URL, or send Onto the page that links to the file instead of the file itself. Retrying won't change the file type.

Suggested handling in a Node client:

if (data.code === 'UNSUPPORTED_TYPE') {
  // Not a document Onto can read. Skip it.
  return null;
}

See the full error index for the complete catalog with the handling switch statement covering every code at once.