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Monaco Protocol SDK v0.6.1

Simulate Fees Improvements

This release improves the /api/v1/fees/simulate endpoint and SDK to support the 100% balance slider on the frontend and accurate fee estimation for market orders.

New Features

max_quantity — 100% Balance Slider Support

simulateFees() now returns max_quantity: the maximum quantity the authenticated user can buy at the given price, already accounting for fees. Use this directly as the value for a 100% balance slider instead of computing available_balance / price (which ignores fees and causes insufficient balance errors).
New response fields:

Market Order Slippage Buffer

Pass order_type: "MARKET" to get a slippage-adjusted buy_order_lock_amount. This reflects the worst-case execution cost for a market order instead of the exact-price calculation, preventing false “affordable” signals when the actual fill price differs due to slippage.
New request params: New response field:

Updated Types

SimulateFeeParams (@0xmonaco/types):
  • Added order_type?: "LIMIT" | "MARKET"
  • Added slippage_tolerance_bps?: number (0–1000, MARKET only)
SimulateFeeResponse (@0xmonaco/types):
  • Added max_quantity: string | null
  • Added max_quantity_raw: string | null
  • Added slippage_tolerance_bps: number | null

Upgrade Instructions

No breaking changes. All new params and response fields are optional or nullable.
For complete documentation, see the Fees API reference.