Args:
    limit: Maximum number of sifts to return (default 50, max 200)
    offset: Number of sifts to skip for pagination

Args:
    sift_id: The sift identifier
    limit: Maximum number of records to return (default 20, max 100)
    offset: Number of records to skip (ignored when cursor is provided)
    cursor: Opaque pagination cursor from a previous call's next_cursor field

Args:
    sift_id: The sift identifier
    natural_language: The question to answer (e.g. "What is the total by client?")

Args:
    limit: Maximum number of folders to return (default 100, max 200)
    offset: Number of folders to skip for pagination

Args:
    folder_path: Folder path (e.g. '/invoices/2025')

Args:
    sift_id: The sift identifier
    record_id: The record identifier

Args:
    name: Human-readable sift name
    instructions: Natural language extraction instructions (e.g. "client, date, total")
    folder_path: Optional folder path to link (e.g. '/invoices/2025'); created if it doesn't exist

Args:
    sift_id: The sift identifier
    name: New name (leave empty to keep current)
    instructions: New instructions (leave empty to keep current)

Args:
    sift_id: The sift identifier

Args:
    folder_path: Target folder path (e.g. '/invoices/2025'). Created if it doesn't exist.
    filename: Original filename (used for display)
    content_base64: Base64-encoded file bytes

Args:
    document_id: The document identifier
    sift_id: The sift to extract with

Args:
    document_id: The document identifier
    sift_id: The sift identifier

Returns:
    {"status": "queued|running|completed|failed", "error": "..." (on failure)}

Args:
    sift_id: The sift identifier
    filter: Mongo-subset filter dict e.g. {"total": {"$gt": 1000}}
    sort: Optional sort spec e.g. [["date", -1]]
    limit: Max records to return (default 50)
    cursor: Opaque pagination cursor from a previous call

Returns:
    {"records": [...], "next_cursor": "..." | null}

Args:
    sift_id: The sift identifier
    pipeline: MongoDB aggregation pipeline stages
              e.g. [{"$group": {"_id": "$client", "total": {"$sum": "$total"}}}]

Returns:
    Array of aggregated rows