Get orderbook depth

Get aggregated orderbook depth with buy (bids) and sell (asks) orders.

Authentication required - The returned available_quantity excludes your own orders.

Precision:

• precision=2: Groups orders to 2 decimal places (e.g., 1.25, 1.26)
• precision=4: Groups orders to 4 decimal places (e.g., 1.2500, 1.2501)

Levels:

• levels=0 or omitted: Returns all price levels
• levels=10: Returns top 10 levels per side (10 bids, 10 asks)