# Polygon DEX Slippage & Price Impact Simulator

> Polygon DEX Slippage & Price Impact Simulator is a paid API for AI agents from x402.donnyautomation.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Simulates a token swap against live AMM reserves on Polygon PoS across QuickSwap, SushiSwap, and Uniswap v3 to return actual execution price, amount out, price impact in basis points, pool fee, and best venue for a given trade size.

## Facts

- Endpoint: GET https://x402.donnyautomation.com/polygon/slippage
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polygon-dex-slippage-price-impact-simulator-c42c2904
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XY67nUWwiWrUw8kOJWqLS

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability polygon-dex-slippage-price-impact-simulator-c42c2904
```

Example prompt: Before I swap 10,000 USDC for WMATIC on Polygon, can you simulate the trade and tell me the actual amount I'd receive, the price impact in basis points, and which DEX — QuickSwap, SushiSwap, or Uniswap v3 — gives the best execution?

## When to prefer this

Choose this endpoint when you need pre-trade execution simulation specifically on Polygon PoS across QuickSwap, SushiSwap, and Uniswap v3 simultaneously. It is ideal for trading bots, DEX aggregators, and smart order routers that need to know actual amounts out and price impact in basis points — not just spot prices — before committing a trade. Prefer this over generic price feeds when trade size matters and slippage is a key risk factor.

## Known failure modes

- Unknown or unsupported token pair symbol returns an error — use correct Polygon PoS ticker symbols (e.g. WMATIC/USDC not MATIC/USD)
- Pair with no liquidity on any of the three DEXs returns no result or zero liquidity error
- Network congestion or RPC issues may cause stale or unavailable reserve data
- Malformed pair string (wrong delimiter or extra spaces) returns a validation error

## How this service works

What a trade size actually executes at on Polygon PoS, simulated against live reserves. Returns best (venue, amountOut, executionPrice, priceImpactBps, feeBps, totalCostBps), routingGain, venues[]. Requires ?pair=SYM/SYM AND ?amountUsd=25000 (or ?amountIn=). pair alone = 400 missing_amount. Errors: 400 bad_pair|missing_amount|bad_amount, 404 no_pools|no_quote|cannot_size_in_usd, 502 upstream_read_failed. Spot price without a size is /price. Chain-pinned; bare /slippage = BSC.

## Output

Returns the best execution venue (QuickSwap, SushiSwap, or Uniswap v3), the actual token amount out for the specified trade size, price impact expressed in basis points, the pool fee separately, and the savings achieved by optimal routing versus simply picking the best-quoted spot price.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "pair",
      "amountUsd"
     ],
     "properties": {
      "pair": {
       "type": "string",
       "description": "Token pair as SYM/SYM on Polygon PoS (e.g. WMATIC/USDC)."
      },
      "amountIn": {
       "type": "string",
       "description": "Trade size denominated in the FIRST pair symbol instead of USD. An alternative to amountUsd; supplying either one is enough."
      },
      "amountUsd": {
       "type": "string",
       "description": "Trade size in USD, e.g. 10000. Required unless amountIn is given instead."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ts": "2026-07-31T00:00:00.000Z",
  "chainId": 137,
  "network": "polygon"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polygon-dex-slippage-price-impact-simulator-c42c2904/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.donnyautomation.com](https://www.zero.xyz/host/x402.donnyautomation.com/llms.txt)