timeframe is 1m, 5m, 15m, 30m, 1h, 4h, 1d (default 1m); since is Unix milliseconds. limit defaults to 500 and caps at 1,000. cursor follows Pagination.
The body is an array of [timestamp, open, high, low, close, baseVolume, quoteVolume] tuples, ascending by time. Timestamp is a number in milliseconds; OHLC and volume are decimal strings. Unknown symbols or timeframes return 400. For Testnet-Only Perps use market candles.