Crypto Slippage & Market Impact API

What a crypto trade actually costs once it eats into the order book — computed live from Binance's full depth feed (up to 5000 levels per side), no key, nothing stored. Top-of-book price is a fiction for anything but the smallest order: a real market order walks down the book, filling progressively worse levels, and the gap between the quoted price and the realised average fill is slippage. The estimate endpoint takes a pair, a side (buy or sell) and a size — in quote currency (notional, e.g. $250,000) or in base coin (quantity) — walks the live book level by level and returns the average fill price, the slippage versus the mid and versus top-of-book, the price impact (how far the last filled level sits from mid), the number of levels consumed and whether the book even holds enough liquidity to fill. The depth endpoint returns a liquidity profile: top bid/ask, mid, spread and the cumulative bid- and ask-side liquidity sitting within ±0.1%, ±0.25%, ±0.5%, ±1% and ±2% of mid, plus the book imbalance — a one-glance read on how deep and how lopsided a market is. The symbols endpoint lists tradable pairs. This is the execution-cost / market-impact analytics cut for crypto — distinct from the raw exchange order-book feed, from VWAP-on-candles, and from the price, ticker and quote APIs in the catalogue. Pairs are Binance symbols (BTCUSDT) or a coin=BTC&quote=USDT form.