# Arbitrum Top of Order Book

> Arbitrum Top of Order Book is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-02).

Returns the best bid and ask prices from the Coinbase Exchange public order book for the ARB-USD trading pair.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/demand-market-arbitrum-orderbook-top?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arbitrum-top-of-order-book-04644ec7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Ci0DOQfZ63rzt5_ktbI_4

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 arbitrum-top-of-order-book-04644ec7 -d '<json body>'
```

Example prompt: What's the current best bid and ask for ARB-USD on the Coinbase order book right now?

## When to prefer this

Choose this endpoint when you need real-time top-of-book bid/ask data specifically for the ARB-USD pair from Coinbase Exchange. It is ideal for trading bots, spread monitoring, pre-trade price checks, or cross-exchange arbitrage detection. Prefer this over full order book endpoints when only the best bid and ask are needed, reducing cost and latency.

## Known failure modes

- Invalid product ID returns an error response — only valid Coinbase USD product IDs are accepted
- Service unavailability during market downtime or maintenance windows
- Rate limiting or payment failures if USDC payment is not properly handled
- Stale data if the order book has no active orders at the top level

## How this service works

Arbitrum Top of order book: Return the best bid and ask levels from the public order book. Coinbase Exchange public USD market data; not investment advice.

## Output

Returns the best bid (highest buy offer) and best ask (lowest sell offer) from the Coinbase Exchange public order book for the requested product, typically ARB-USD. This allows agents to determine the current market spread and reference price for Arbitrum tokens in USD.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "product": {
   "type": "string",
   "default": "ARB-USD",
   "description": "Coinbase USD product ID; defaults to ARB-USD."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arbitrum-top-of-order-book-04644ec7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from market.datapackvibe.com](https://www.zero.xyz/host/market.datapackvibe.com/llms.txt)