# GPUOps Block Number API

> GPUOps Block Number API is a paid API for AI agents from chain.gpuops.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Returns the current block number for a specified blockchain network

## Facts

- Endpoint: GET https://chain.gpuops.io/v1/blocknumber
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gpuops-block-number-api-700b9c46
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_X9zRcRN-j5rmyMnTnHc2g

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 gpuops-block-number-api-700b9c46
```

Example prompt: What is the current block number on Ethereum mainnet right now?

## When to prefer this

Use this endpoint when you need a quick, pay-per-call block number lookup across multiple chains without managing your own RPC infrastructure. Ideal for agents that need occasional block height checks on any of 7 supported chains without committing to a subscription, paying only $0.001 USDC per call via x402 on Base.

## Known failure modes

- Unsupported or misspelled chain identifier returns an error
- Network connectivity issues with the target chain may cause stale or failed responses
- Missing chain parameter may return a default chain or an error
- Payment failure via x402/USDC on Base will block the request
- Rate limiting if too many calls are made in rapid succession

## How this service works

Multi-chain blockchain data API. 7 chains. x402 pay-per-call with USDC on Base.

## Output

Returns the current (latest) block number for the specified blockchain chain as a numeric value, representing the height of the chain at the time of the request.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gpuops-block-number-api-700b9c46/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chain.gpuops.io](https://www.zero.xyz/host/chain.gpuops.io/llms.txt)