# ETH Mainnet ETH Blocknumber

> ETH Mainnet ETH Blocknumber is a paid API for AI agents from ari001.tailb4ac3a.ts.net, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-31).

Returns the latest Ethereum mainnet block number via the eth_blockNumber RPC method.

## Facts

- Endpoint: GET https://ari001.tailb4ac3a.ts.net/v1/ventures/x402_eth_reads_v1/eth_mainnet_eth_blocknumber?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/eth-mainnet-eth-blocknumber-5297dbda
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-0IUwoyapfEr521NwhvFx

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 eth-mainnet-eth-blocknumber-5297dbda
```

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, cheap, single-purpose lookup of the current Ethereum mainnet block number without constructing a full RPC call yourself. Ideal for agents that need to timestamp events by block height, check chain tip progression, or verify node sync status. Prefer this over a full Ethereum node RPC client when you want a pay-per-use, no-infrastructure approach.

## Known failure modes

- Upstream Ethereum RPC node unavailable — returns 5xx error
- Payment not processed correctly — returns 402 Payment Required
- Block number temporarily stale if upstream node is lagging
- Network timeout if the backing RPC is slow to respond

## How this service works

Returns the latest Ethereum mainnet block number via eth_blockNumber. Takes no parameters. Base RPC read of an address, block or transaction.

## Output

Returns the current Ethereum mainnet block number, typically as a hex string (e.g. '0x12A05F2'), representing the height of the latest confirmed block on the Ethereum mainnet chain.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "ok",
      "service"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "hex": {
       "type": [
        "string",
        "null"
       ]
      },
      "chain": {
       "type": "string"
      },
      "error": {
       "type": "string",
       "description": "present when ok is false"
      },
      "method": {
       "type": "string"
      },
      "result": {
       "type": "integer"
      },
      "service": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/eth-mainnet-eth-blocknumber-5297dbda/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ari001.tailb4ac3a.ts.net](https://www.zero.xyz/host/ari001.tailb4ac3a.ts.net/llms.txt)