# PerCall Order Book Depth — Real-time Crypto Market Data

> PerCall Order Book Depth — Real-time Crypto Market Data is a paid API for AI agents from percall.kimi.pro, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-13).

Returns a live order book snapshot (top bids and asks with quantities) for a given crypto trading pair, paid per request via x402/USDC on Base.

## Facts

- Endpoint: GET https://percall.kimi.pro/api/x402/depth/%7Bsymbol%7D
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/percall-order-book-depth-real-time-crypto-market-data-0c42715b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3Yph91AtViNPxVkUeNim1

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 percall-order-book-depth-real-time-crypto-market-data-0c42715b
```

Example prompt: Pull the current order book depth for BTCUSDT — I need the top bids and asks with quantities right now.

## When to prefer this

Choose this endpoint when you need real-time bid/ask depth data with no account setup or API key management — ideal for AI agents making one-off or infrequent queries where a subscription is overkill. Prefer this over exchange WebSocket APIs when you want pay-per-use pricing and don't need a persistent stream. Best for spot checks on liquidity, spread analysis, or pre-trade market impact estimation.

## Known failure modes

- Invalid or unrecognized symbol (e.g. typo or delisted pair) returns an error
- HTTP 402 payment required if x402 payment flow is not completed
- Network or upstream Binance data unavailability may cause timeouts or stale data
- Symbol must match Binance naming convention exactly (e.g. BTCUSDT not BTC/USDT)

## How this service works

PerCall is an x402 payment gateway selling live crypto market data to AI agents and developers. No accounts, no API keys: request, receive HTTP 402, pay in USDC on Base, get data.

## Output

A JSON object containing the trading pair symbol, a timestamp, a lastUpdateId, and two arrays — bids and asks — each containing price-quantity pairs (as strings) representing the top levels of the live order book.

## 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"
    },
    "pathParams": {
     "type": "object"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "symbol"
     ],
     "properties": {
      "symbol": {
       "type": "string",
       "description": "Trading pair symbol as used by Binance, e.g. BTCUSDT."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "asks": [
   [
    "67432.20",
    "0.318"
   ]
  ],
  "bids": [
   [
    "67432.10",
    "0.521"
   ]
  ],
  "symbol": "BTCUSDT",
  "timestamp": "2026-08-28T00:00:00.000Z",
  "lastUpdateId": 741258963
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/percall-order-book-depth-real-time-crypto-market-data-0c42715b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from percall.kimi.pro](https://www.zero.xyz/host/percall.kimi.pro/llms.txt)