# HALOWERK marktwerk Slippage Estimator

> HALOWERK marktwerk Slippage Estimator is a paid API for AI agents from markt.netzhandwerker.de, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-15).

Estimates order slippage (and optionally taker fees) for a given trade size and direction on a specified crypto exchange's live order book

## Facts

- Endpoint: POST https://markt.netzhandwerker.de/slippage
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-marktwerk-slippage-estimator-3f77aa19
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZcfTopfOFaRTTNu28b33d

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 halowerk-marktwerk-slippage-estimator-3f77aa19 -d '<json body>'
```

Example prompt: What's the estimated slippage for buying 5 ETH with USDC on Binance's order book, including taker fees?

## When to prefer this

Use this endpoint when you need a real-time, order-book-aware slippage estimate for a specific crypto trade before execution — especially for large orders where market impact matters. It supports multiple top-tier venues (Binance, Coinbase, Kraken, OKX, Bybit) and can include taker fees for a fully loaded cost estimate, making it ideal for pre-trade analysis, routing decisions, and execution quality benchmarking.

## Known failure modes

- Invalid symbol format (not matching BASE/QUOTE pattern) returns a validation error
- Unsupported venue name returns an enum validation error
- Size of zero or negative returns exclusiveMinimum validation error
- Order book data unavailable for the requested pair/venue at query time
- Payment failure via x402 protocol (insufficient USDC balance or incorrect payment)
- Rate limiting if too many requests are submitted in rapid succession

## How this service works

HALOWERK marktwerk — bezahlte Endpunkte nach x402. Preise in USDC auf Base Mainnet.

## Output

Returns the estimated fill price for the specified order, reflecting how far the execution price deviates from the best bid/ask due to order book depth (slippage). Optionally includes the taker fee for the entry tier added on top of the fill price, giving the all-in effective execution cost.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "side": {
   "enum": [
    "buy",
    "sell"
   ],
   "type": "string",
   "description": "buy consumes the ask side, sell the bid side."
  },
  "size": {
   "type": "number",
   "description": "Order size, in the unit given by size_unit.",
   "exclusiveMinimum": 0
  },
  "venue": {
   "enum": [
    "binance",
    "coinbase",
    "kraken",
    "okx",
    "bybit"
   ],
   "type": "string",
   "default": "binance",
   "description": "Exchange whose book is used."
  },
  "symbol": {
   "type": "string",
   "pattern": "^[A-Za-z0-9]{2,15}/[A-Za-z0-9]{2,15}$",
   "description": "Trading pair as BASE/QUOTE, for example ETH/USDC."
  },
  "size_unit": {
   "enum": [
    "base",
    "quote"
   ],
   "type": "string",
   "default": "base",
   "description": "base means size is in BASE, quote means size is in QUOTE."
  },
  "include_fees": {
   "type": "boolean",
   "default": false,
   "description": "Adds the taker fee of the entry tier on top of the fill price."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-marktwerk-slippage-estimator-3f77aa19/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from markt.netzhandwerker.de](https://www.zero.xyz/host/markt.netzhandwerker.de/llms.txt)