> ## Documentation Index
> Fetch the complete documentation index at: https://docs.rampartlabs.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Multi-DEX Router

> Best-route swap quotes across 6 DEXes simultaneously

<Info>
  The router queries Kuru, Uniswap V3, PancakeSwap V3, PancakeSwap V2, Uniswap V2, and OpenOcean in parallel via `Promise.allSettled`, returning the best available output amount. OpenOcean is queried via REST API and is silently skipped if unavailable.
</Info>

## Overview

The Multi-DEX Router is a DEX aggregator that fans out quote requests to all 6 supported sources simultaneously and surfaces the route with the highest `amountOut`. Price impact is included where the underlying DEX exposes it.

**Supported DEXes:**

* Kuru (native orderbook AMM, MON pairs)
* Uniswap V3
* PancakeSwap V3
* PancakeSwap V2
* Uniswap V2
* OpenOcean (REST API)

## Types

```typescript theme={null}
type DexName = 'kuru' | 'uniswap-v2' | 'uniswap-v3' | 'pancake-v2' | 'pancake-v3' | 'openocean'

interface SwapRoute {
  dex: DexName
  amountOut: string
  priceImpact?: number
}

interface RouterResult {
  bestDex: DexName
  amountOut: string
  allRoutes: SwapRoute[]
  timestamp: number
}

interface ArbitrageAlert {
  buyDex: DexName
  sellDex: DexName
  buyPrice: number
  sellPrice: number
  spreadPct: number
  profitable: boolean
}
```

## Functions

### `getBestSwapRoute`

Queries all 6 DEXes in parallel and returns the route with the highest `amountOut`.

```typescript theme={null}
getBestSwapRoute(
  tokenIn: string,
  tokenOut: string,
  amountIn: string
): Promise<RouterResult>
```

| Parameter  | Type     | Description                                            |
| ---------- | -------- | ------------------------------------------------------ |
| `tokenIn`  | `string` | Input token address (use `0x000...000` for native MON) |
| `tokenOut` | `string` | Output token address                                   |
| `amountIn` | `string` | Amount in wei (as string to avoid BigInt overflow)     |

Returns a `RouterResult` with `bestDex`, `amountOut`, `allRoutes` sorted by output descending, and `timestamp`.

### `getAllSwapQuotes`

Returns all available quotes sorted by `amountOut` descending. Useful when you want to display a comparison UI or inspect every route.

```typescript theme={null}
getAllSwapQuotes(
  tokenIn: string,
  tokenOut: string,
  amountIn: string
): Promise<SwapRoute[]>
```

### `detectDexArbitrage`

Detects price discrepancies greater than 0.5% between any two DEXes for a given token pair. Returns `null` if no profitable spread is found.

```typescript theme={null}
detectDexArbitrage(
  tokenA: string,
  tokenB: string
): Promise<ArbitrageAlert | null>
```

## Usage

```typescript theme={null}
import { getBestSwapRoute, getAllSwapQuotes } from 'rampart-monad'

const MON  = '0x0000000000000000000000000000000000000000'
const USDC = '0xf817257fed379853cDe0fa4F97AB987181B1E5Ea'

const result = await getBestSwapRoute(MON, USDC, '1000000000000000000')
console.log(`Best: ${result.bestDex} → ${result.amountOut} USDC`)
// → Best: kuru → 354000 USDC

// Compare all DEX quotes
const quotes = await getAllSwapQuotes(MON, USDC, '1000000000000000000')
for (const q of quotes) {
  console.log(`${q.dex}: ${q.amountOut}`)
}
```

## Arbitrage Detection

```typescript theme={null}
import { detectDexArbitrage } from 'rampart-monad'

const MON  = '0x0000000000000000000000000000000000000000'
const USDC = '0xf817257fed379853cDe0fa4F97AB987181B1E5Ea'

const alert = await detectDexArbitrage(MON, USDC)
if (alert && alert.profitable) {
  console.log(`Buy on  ${alert.buyDex}  @ $${alert.buyPrice}`)
  console.log(`Sell on ${alert.sellDex} @ $${alert.sellPrice}`)
  console.log(`Spread: ${alert.spreadPct.toFixed(2)}%`)
}
```

## Notes

* `amountIn` must be a string in wei to avoid JavaScript `BigInt` precision loss.
* Routes from DEXes that return an error or timeout are excluded from `allRoutes` - the result always reflects only successful responses.
* OpenOcean quotes are fetched via their public REST API. If the endpoint is unavailable the router continues with the remaining 5 sources.
* Kuru is a native orderbook AMM optimised for MON pairs and often returns the best rate for MON/USDC.