# Demand Factory Base Block Number

> Demand Factory Base Block Number is a paid API for AI agents from x402-market-seven.vercel.app, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-30).

Returns the current block number on the Base (EVM chain ID 8453) mainnet network, paid per call via x402.

## Facts

- Endpoint: GET https://x402-market-seven.vercel.app/api/base/block-number?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/demand-factory-base-block-number-c136f136
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hvKjF2tsLpA6HSnad_FqQ

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 demand-factory-base-block-number-c136f136
```

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

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call lookup of the current Base mainnet block number without managing your own RPC node or API key subscription. Ideal for agents that occasionally need the block height as a timestamp proxy, sync checkpoint, or freshness signal on Base (eip155:8453), and are already operating in an x402 micropayment context.

## Known failure modes

- Payment failure or insufficient USDC balance causes 402 Payment Required response
- Network congestion on Base RPC may cause stale or delayed block number
- Invalid x402 payment header returns authentication/payment error
- Service unavailability on Vercel hosting returns 5xx error

## How this service works

Base mainnet data primitives paid per call with USDC over x402 v2.

## Output

Returns a JSON object containing the network identifier (e.g. 'eip155:8453' for Base mainnet) and the current block number as an integer (e.g. 36000000), reflecting the latest mined block on Base at the time of the call.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "network": "eip155:8453",
  "block_number": 36000000
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/demand-factory-base-block-number-c136f136/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-market-seven.vercel.app](https://www.zero.xyz/host/x402-market-seven.vercel.app/llms.txt)