# Obol Order Book Top

> Obol Order Book Top is a paid API for AI agents from obol.danieldutoit.net, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-23).

Returns the top-of-book (best bid and best ask) snapshot from a cryptocurrency exchange order book for a given trading pair.

## Facts

- Endpoint: GET https://obol.danieldutoit.net/v1/markets/orderbook-top?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/obol-order-book-top-78c61ebd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_205L2n7aO29kIkVLfNtdC

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 obol-order-book-top-78c61ebd
```

Example prompt: What's the current top of book for BTC/USD on Coinbase — give me the best bid, best ask, and spread right now using Obol's verified order book data.

## When to prefer this

Choose this endpoint when you need verified, structured order book top-of-book data (best bid/ask + spread) for major crypto pairs from a specific exchange, especially when you require a micropayment-native API settled in USDC on Base via x402 without API key management. Prefer this over free, unverified market data sources when data provenance and payment-per-call economics matter.

## Known failure modes

- Trading pair not found on the requested exchange returns found: false
- Invalid or unsupported exchange name results in no data
- Timestamp out of available historical range returns no snapshot
- Network or payment failure via x402 protocol returns a payment-required error
- Malformed query parameters cause a 4xx response

## How this service works

Obol sells verified blockchain data over x402, settled in USDC on Base.

## Output

A JSON object containing the best bid (price and volume) and best ask (price and volume) for the requested trading pair, along with the spread as a percentage, the exchange name, the base and quote currencies, the observed timestamp, a match type describing coverage quality, and a disclaimer noting the data is historical and informational.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "base": "BTC",
  "found": true,
  "quote": "USD",
  "coverage": {
   "match_type": "exact_exchange_timestamp_base_and_quote",
   "maximum_results": 1
  },
  "exchange": "COINBASE",
  "snapshot": {
   "best_ask": {
    "price": 63402.2,
    "volume": 0.054
   },
   "best_bid": {
    "price": 63402.1,
    "volume": 0.364
   },
   "observed_at": "2026-08-13T00:05:00.000Z",
   "spread_percent": 0.0001577234823429269
  },
  "timestamp": "1786579500",
  "disclaimer": "Historical exchange observation for informational use; not investment advice."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/obol-order-book-top-78c61ebd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from obol.danieldutoit.net](https://www.zero.xyz/host/obol.danieldutoit.net/llms.txt)