# Crest Block Preview

> Crest Block Preview is a paid API for AI agents from data.crestsystems.ai, paid per call via x402, $0.002/call, status down (last checked 2026-09-15).

Fetches a preview of the latest block data for a specified EVM-compatible blockchain chain

## Facts

- Endpoint: GET https://data.crestsystems.ai/data/block/preview
- Price: $0.002/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crest-block-preview-1d63ba6d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lDGZN1yD9MhCN--aUQ9Ll

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 crest-block-preview-1d63ba6d
```

Example prompt: What does the latest block on Base look like — block number, gas used, and transaction count?

## When to prefer this

Use this endpoint when you need a quick, lightweight snapshot of the latest block on a major EVM chain (Base, Ethereum, Arbitrum, Polygon) — especially in pay-per-request workflows where you only want to pay for what you need. Prefer this over heavier RPC node integrations when you just need block number, gas, and tx count without running full node infrastructure.

## Known failure modes

- Missing required 'chain' parameter returns validation error
- Unsupported chain value (not base/ethereum/arbitrum/polygon) returns error
- Payment failure via x402 USDC on Base mainnet results in 402 response
- Service unavailable or upstream node error returns 5xx response

## How this service works

Crypto market data, DeFi analytics, and x402 ecosystem intelligence via pay-per-request USDC on Base mainnet.

## Output

Returns a JSON object with block details for the requested chain, including the chain name, current block number, gas used in that block, and the number of transactions included.

## Example request

```json
{
 "chain": "base"
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "block": {
   "chain": "base",
   "number": 46074582,
   "gas_used": 12000000,
   "tx_count": 85
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crest-block-preview-1d63ba6d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from data.crestsystems.ai](https://www.zero.xyz/host/data.crestsystems.ai/llms.txt)