# Crypto Order Book Depth & Slippage Estimator

> Crypto Order Book Depth & Slippage Estimator is a paid API for AI agents from crypto-asistent.com, paid per call via x402, $0.04/call, status unknown (last checked 2026-10-13).

Returns live order book depth analysis for a given notional size on Bybit and OKX, including average fill price, slippage in bps and dollars, spread, and which venue is cheaper.

## Facts

- Endpoint: POST https://crypto-asistent.com/api/x402/data/orderbook-depth?utm_source=zero.xyz
- Price: $0.04/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crypto-order-book-depth-slippage-estimator-546565c3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_F8GxFQS-1o2hySIdrMwl0

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 crypto-order-book-depth-slippage-estimator-546565c3 -d '<json body>'
```

Example prompt: Before I buy $75,000 worth of ETH, check the live order book on Bybit and OKX and tell me the expected fill price, slippage in basis points, and which venue would be cheaper for that size.

## When to prefer this

Use this endpoint when you need real pre-trade cost transparency for a specific notional size — not just a spot price, but the actual expected fill price accounting for order book depth and slippage across Bybit and OKX. Prefer it over simple price feeds when executing or planning trades above ~$10,000 where slippage materially affects cost, or when comparing venue execution quality. Unlike generic price APIs, this endpoint walks the live book at your exact size and returns a venue recommendation.

## Known failure modes

- Order book cannot absorb requested notional size — returned as 'unfilled' with no price estimate
- Invalid or unsupported trading pair causes error
- Stale or temporarily unavailable order book data from Bybit or OKX
- Missing required 'input' body field causes schema validation failure
- Network timeout fetching live order book snapshots

## How this service works

What a trade actually costs before it is placed: live order book depth on Bybit and OKX, walked at your size. Give it a notional in dollars and it returns the average fill price, slippage against mid in basis points and dollars, the spread, the depth within 1% of mid, and which venue is cheaper for that exact size — separately for buying and selling. A size the book cannot absorb is reported as unfilled, never priced by extrapolation.

## Output

Returns a structured breakdown for both buy and sell sides: average fill price, slippage in basis points and in dollar terms, the bid-ask spread, order book depth within 1% of mid-price, and a recommendation of which venue (Bybit or OKX) is cheaper for the requested notional. If the order book cannot absorb the requested size, the response reports the trade as unfilled rather than extrapolating a 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [],
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crypto-order-book-depth-slippage-estimator-546565c3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from crypto-asistent.com](https://www.zero.xyz/host/crypto-asistent.com/llms.txt)