# HTTPay Price Impact Estimator

> HTTPay Price Impact Estimator is a paid API for AI agents from httpay.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Estimates price impact and slippage for a token swap on Base by checking pool depth across UniswapV3 and Aerodrome DEXes

## Facts

- Endpoint: POST https://httpay.xyz/api/price-impact
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/httpay-price-impact-estimator-55fbd604
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KSeQong2Cb2BUb_D3vyxM

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 httpay-price-impact-estimator-55fbd604 -d '<json body>'
```

Example prompt: Before I swap $5000 worth of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) to WETH (0x4200000000000000000000000000000000000006) on Base, can you check the price impact and tell me the estimated slippage and the max trade size I should use?

## When to prefer this

Use this endpoint when you need a pre-trade price impact estimate on Base DEXes (UniswapV3 and Aerodrome) without needing an API key or subscription — ideal for agents managing DeFi trades that want to avoid excessive slippage on large swaps

## Known failure modes

- Invalid tokenIn or tokenOut address returns an error
- No liquidity pool found for the token pair returns empty or error
- amountUsd too large or too small may produce unreliable estimates
- Network or RPC issues may cause timeouts
- Payment not settled via x402/USDC returns 402

## How this service works

Estimate price impact before executing a swap. Params: ?tokenIn=0x...&tokenOut=0x...&amountUsd=1000. Checks pool depth on UniV3 + Aerodrome. Returns estimated slippage %, recommended max trade size, pool stats.

## Output

Returns the estimated slippage percentage for the proposed swap, the recommended maximum trade size to minimize price impact, and pool statistics from UniswapV3 and Aerodrome liquidity pools on Base

## Example request

```json
{
 "tokenIn": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
 "tokenOut": "0x4200000000000000000000000000000000000006",
 "amountUsd": 5000
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "description": "Estimate price impact before executing a swap. Params: ?tokenIn=0x...&tokenOut=0x...&amountUsd=1000. Checks pool depth on UniV3 + Aerodrome. Returns estimated slippage %, recommended max trade size, pool stats."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/httpay-price-impact-estimator-55fbd604/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from httpay.xyz](https://www.zero.xyz/host/httpay.xyz/llms.txt)