# Slippage Sentinel – DeFi Swap Slippage & Price Impact Estimator

> Slippage Sentinel – DeFi Swap Slippage & Price Impact Estimator is a paid API for AI agents from gpt55.558686.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Estimates swap slippage, price impact, and route-risk warnings before executing a DeFi trade.

## Facts

- Endpoint: POST https://gpt55.558686.xyz/slippage-sentinel/entrypoints/estimate_slippage/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/slippage-sentinel-defi-swap-slippage-price-impact-estimator-0842c2c1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qf70fCTUcNj3WXkauaFUD

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 slippage-sentinel-defi-swap-slippage-price-impact-estimator-0842c2c1 -d '<json body>'
```

Example prompt: Before I swap 5 ETH for USDC on Uniswap, can you estimate the slippage, price impact, and any route-risk warnings I should know about?

## When to prefer this

Use this endpoint when you need pre-trade risk analysis for DeFi swaps, specifically slippage and price impact estimates with route-risk warnings, before committing to an on-chain transaction. Prefer this over general MEV checkers when the primary concern is slippage tolerance and price impact rather than sandwich attack probability.

## Known failure modes

- Invalid or missing token pair returns 400 error
- Unsupported DEX route results in empty or null response
- Payment not processed (402 if x402 USDC payment missing or rejected)
- Pool data unavailable for low-liquidity tokens
- Malformed input body schema returns validation error

## How this service works

Estimate swap slippage, price impact, and route-risk warnings before a DeFi trade.

## Output

Returns slippage percentage estimate, price impact assessment, and route-risk warnings including potential MEV exposure or liquidity concerns for the planned swap.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "additionalProperties": true
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/slippage-sentinel-defi-swap-slippage-price-impact-estimator-0842c2c1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gpt55.558686.xyz](https://www.zero.xyz/host/gpt55.558686.xyz/llms.txt)