curl -X POST https://api.rapidcall.ai/api/kb/folders/kb_folder_001/pdf \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -F "file=@/path/to/document.pdf"

{
  "document": {
    "id": "doc_004",
    "name": "Product Manual.pdf",
    "type": "pdf",
    "characterCount": 15200,
    "pageCount": 12,
    "createdAt": "2026-04-02T12:00:00Z"
  }
}